Pour voir les autres types de publications sur ce sujet consultez le lien suivant : Polyester polyurethane.
Thèses sur le sujet « Polyester polyurethane »
Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres
Consultez les 46 meilleures thèses pour votre recherche sur le sujet « Polyester polyurethane ».
À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.
Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.
Parcourez les thèses sur diverses disciplines et organisez correctement votre bibliographie.
1
Schmidt, Juliane, Ren Wei, Thorsten Oeser, e. Silva Lukas Andre Dedavid, Daniel Breite, Agnes Schulze et Wolfgang Zimmermann. « Degradation of Polyester Polyurethane by Bacterial Polyester Hydrolases ». Universität Leipzig, 2017. https://ul.qucosa.de/id/qucosa%3A21100.
Texte intégralRésumé :
Polyurethanes (PU) are widely used synthetic polymers. The growing amount of PU used industrially has resulted in a worldwide increase of plastic wastes. The related environmental pollution as well as the limited availability of the raw materials based on petrochemicals requires novel solutions for their efficient degradation and recycling. The degradation of the polyester PU Impranil DLN by the polyester hydrolases LC cutinase (LCC), TfCut2, Tcur1278 and Tcur0390 was analyzed using a turbidimetric assay. The highest hydrolysis rates were obtained with TfCut2 and Tcur0390. TfCut2 also showed a significantly higher substrate affinity for Impranil DLN than the other three enzymes, indicated by a higher adsorption constant K. Significant weight losses of the solid thermoplastic polyester PU (TPU) Elastollan B85A-10 and C85A-10 were detected as a result of the enzymatic degradation by all four polyester hydrolases. Within a reaction time of 200 h at 70 °C, LCC caused weight losses of up to 4.9% and 4.1% of Elastollan B85A-10 and C85A-10, respectively. Gel permeation chromatography confirmed a preferential degradation of the larger polymer chains. Scanning electron microscopy revealed cracks at the surface of the TPU cubes as a result of enzymatic surface erosion. Analysis by Fourier transform infrared spectroscopy indicated that the observed weight losses were a result of the cleavage of ester bonds of the polyester TPU.
2
Kay, Martin John. « Microbial degradation of polyester polyurethane ». Thesis, University of Central Lancashire, 1992. http://clok.uclan.ac.uk/20311/.
Texte intégralRésumé :
During the course of these studies, polyester polyurethane foam has been found to be readily degraded in soil and marine environments. The incorporation of the formulation biocide Vinyzene E.P. reduced the rate and extent of degradation in test material exposed to soil conditions, but was found to be ineffective in preventing degradation when exposed to the marine environment. As a result of these studies, a number of fungi, representing a range of genera, have been isolated, identified, and shown using Kochian principles to degrade polyester polyurethane as a sole source of carbon. A list of isolates is submitted. In addition, a number of bacteria, hitherto unreported as deteriogens of polyester polyurethane, have been isolated and also shown, again using Kochian principles, to degrade polyester polyurethane. In order to effect degradation, the bacteria were found to require supplementation of the basal mineral salts medium with non-defined, complex sources of organic nitrogen, such as yeast extract. Chemical analysis of degraded test material, using FT-IR spectroscopy has provided evidence to suggest that the ester linkage of the polymer was hydrolysed during degradation by a bacterial isolate studied, resulting in marked reductions in the physical properties recorded. No degradation, either in terms of chemical composition or in the physical properties of the polymer was recorded where the test material was inoculated with this isolate in a mineral salts medium supplemented with glucose, suggesting that the enzymes involved in the degradation process were catabolically suppressed and therefore inducible. Extracellular esterase enzyme activity was detected in cellfree supernatants where the mineral salts medium was supplemented with yeast extract, but not in the case where glucose was used. However the addition of the test material did not enhance the level of esterase activity detected. Purification/concentration of these enzymes and characterisation studies using gel filtration chromatography, SDS-PAGE and PAGE were found to support these findings. The results of the present studies suggest that the test material was degraded by the bacterial isolate as a result of co-metabolism.
3
Pavlova, Ewa. « Hyperbranched polyesters for polyurethane coatings : their preparation, structure and crosslinking with polyisocyanates ». Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1172267166280-42303.
Texte intégralRésumé :
In this work, hyperbranched aromatic polyesters-polyphenols based on 4,4-bis(4’ hydroxy¬phenyl)pentanoic acid (BHPPA) were prepared and, according to the authors knowledge, for the first time tested as precursors for polyurethane bulk resins and coatings. Comparison of poly-BHPPA with competing products The materials prepared in this work show better properties than their aliphatic polyester-polyol analoga based on 2,2-bis-(hydroxymethyl)propanoic acid (BHMPA). Especially, the solubility of poly-BHPPA in organic solvents is better and poly-BHPPAs also do not tend to microphase separation during their reaction with isocyanates, in contrast to poly-BHMPAs. The poly-BHPPA and the polyurethane networks made from them display higher Tg values than analogous poly- BHMPA compounds. Because of the high Tg of the reacting and final systems, curing must occur at elevated temperatures (90°C) in order to avoid undercure. The lower reactivity of phenolic OH groups prevents the reaction from being too fast at that temperature. A drawback of the polyurethanes based on the aromatic polyesters-polyols prepared is the lower thermal stability of their urethane bonds, if compared to aliphatic urethanes. An interesting possibility for future investigations would be the modification of the BHPPA monomer in order to change the OH functionality from phenolic to aliphatic OH, e.g. by replacement of the phenolic OH by hydroxymethyl or hydroxyethyl groups (requires a strong modification of the monomer synthesis) or simpler by reacting the phenolic OH of BHPPA with a suitable reagent like oxirane, which would lead to groups like O-CH2-CH2-OH in the place of the phenolic OH. Such a BHPPA modification should in turn yield modified “poly-BHPPA” polycondensates, which would combine the advantages of poly-BHPPA with those of aliphatic OH precursors of polyurethanes. Poly-BHPPA synthesis Hyperbranched polymers of the 4,4-bis-(4’-hydroxyphenyl)pentanoic acid (BHPPA) were synthesized successfully by the catalyzed (by dibutyltin diacetate) polycondensation of BHPPA. The products obtained were oligomers with number average molecular weight ranging from 1800 to 3400 g/mol (polymerization degree of ca. 6 to 12), displaying a first moment of functionality in the range 7 to 14. Such products were good OH precursors for the preparation of polyurethane coatings, because higher functional polymers would gel at low conversions. The analysis of the functional groups (determination of acid and hydroxyl numbers) and the 1H-NMR and the 13C-NMR spectroscopy were found to be good methods for the determination of molecular weights. The polydispersity of the poly-BHPPA products was in the range 3.5 to 6. Their degree of branching was found to be in the range 0.36 to 0.47. Poly-BHPPA containing aliphatic polyols as core monomers were also prepared successfully. Difunctional and trifunctional core monomers usually reached a full conversion of their OH groups, while the tetra- and hexafunctional core monomers were converted only to 89%. In all these products however, a considerable amount, usually even a majority, of the polymer molecules were core free. The poly-BHPPA products prepared displayed relatively high glass transition temperatures, in the range of 84°C to 114°C, obviously due to interactions between the phenol groups and to hydrogen bridging. The thermal stability of these products was also high, with decomposition occurring near 350°C (at a heating rate of 10°C / min) Kinetics investigations of the poly-BHPPA reactivity towards isocyanates The poly-BHPPA are polyphenols and were expectedly found to react significantly slower with isocyanates than aliphatic alcohols. The reactivity of poly BHPPA was also found to be somewhat lower than that of the monofunctional, low molar-mass 4 ethylphenol. Hexamethylene diisocyanate trimer, Desmodur N3300, was found to be more reactive than hexamethylene diisocyanate (HDI) or butyl isocyanate in all experiments, possibly due to a substitution effect. The substitution effect can be explained by a change of microenvironment caused by conversion of isocyanate group and OH group into urethane groups. The reactions of low-molecular-mass alcohols or phenols with low molecular weight isocyanates followed well the 2nd order kinetics, while the reactions of poly-BHPPA with isocyanates show deviations from ideal 2nd order kinetics at higher conversions. All the kinetics experiments were carried out under catalysis by dibutyltin dilaurate. This catalyst inhibits the undesired reaction of isocyanate groups with moisture. It was also found that the catalysis was necessary to reach reasonable curing times for poly-BHPPA based polyurethane networks. The uncatalyzed systems reacted extremely slowly. Preparation of polyurethane networks from poly-BHPPA The poly BHPPA products prepared were used successfully as OH functional precursors of polyurethane networks. The networks prepared contained only very low sol fractions. Acetone and also ethylene diglycol dimethylether (diglyme) were found to be good swelling solvents for the networks prepared, while methyl propyl ketone was a much poorer solvent and aromatic compounds like toluene or xylene practically did not swell the poly BHPPA based polyurethanes. The networks prepared contain a relatively high amount of cyclic bonds, 40 to 50% in the finally cured state, which is an expected result for systems with precursors of high functionality and with small distances between the functional groups. The temperature of glass transition (Tg) of the networks prepared (ranging from 68°C to 126°C) depends of the poly BHPPA precursor used: it increases with increasing molecular mass and with increasing core functionality. The choice of the isocyanate crosslinker also influences Tg: the networks made from HDI show higher Tg values, than networks made from the same poly BHPPA but crosslinked with Desmodur N3300 (Tri HDI). The urethane bonds in the networks prepared start to decompose near 140°C. The easier degradation of PU with aromatic urethane bonds is a disadvantage in comparison with aliphatic polyurethanes, whose decomposition starts at 200°C. The surfaces of polyurethane coatings prepared are smooth, displaying a roughness of ca. 20-25 nm, and relatively hydrophilic: the contact angle with water was found to be near 80°. The prepared networks are also relatively hard, possessing the Shore D hardness of 70.
4
Pavlova, Ewa. « Hyperbranched polyesters for polyurethane coatings : their preparation, structure and crosslinking with polyisocyanates ». Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A24962.
Texte intégralRésumé :
In this work, hyperbranched aromatic polyesters-polyphenols based on 4,4-bis(4’ hydroxy¬phenyl)pentanoic acid (BHPPA) were prepared and, according to the authors knowledge, for the first time tested as precursors for polyurethane bulk resins and coatings. Comparison of poly-BHPPA with competing products The materials prepared in this work show better properties than their aliphatic polyester-polyol analoga based on 2,2-bis-(hydroxymethyl)propanoic acid (BHMPA). Especially, the solubility of poly-BHPPA in organic solvents is better and poly-BHPPAs also do not tend to microphase separation during their reaction with isocyanates, in contrast to poly-BHMPAs. The poly-BHPPA and the polyurethane networks made from them display higher Tg values than analogous poly- BHMPA compounds. Because of the high Tg of the reacting and final systems, curing must occur at elevated temperatures (90°C) in order to avoid undercure. The lower reactivity of phenolic OH groups prevents the reaction from being too fast at that temperature. A drawback of the polyurethanes based on the aromatic polyesters-polyols prepared is the lower thermal stability of their urethane bonds, if compared to aliphatic urethanes. An interesting possibility for future investigations would be the modification of the BHPPA monomer in order to change the OH functionality from phenolic to aliphatic OH, e.g. by replacement of the phenolic OH by hydroxymethyl or hydroxyethyl groups (requires a strong modification of the monomer synthesis) or simpler by reacting the phenolic OH of BHPPA with a suitable reagent like oxirane, which would lead to groups like O-CH2-CH2-OH in the place of the phenolic OH. Such a BHPPA modification should in turn yield modified “poly-BHPPA” polycondensates, which would combine the advantages of poly-BHPPA with those of aliphatic OH precursors of polyurethanes. Poly-BHPPA synthesis Hyperbranched polymers of the 4,4-bis-(4’-hydroxyphenyl)pentanoic acid (BHPPA) were synthesized successfully by the catalyzed (by dibutyltin diacetate) polycondensation of BHPPA. The products obtained were oligomers with number average molecular weight ranging from 1800 to 3400 g/mol (polymerization degree of ca. 6 to 12), displaying a first moment of functionality in the range 7 to 14. Such products were good OH precursors for the preparation of polyurethane coatings, because higher functional polymers would gel at low conversions. The analysis of the functional groups (determination of acid and hydroxyl numbers) and the 1H-NMR and the 13C-NMR spectroscopy were found to be good methods for the determination of molecular weights. The polydispersity of the poly-BHPPA products was in the range 3.5 to 6. Their degree of branching was found to be in the range 0.36 to 0.47. Poly-BHPPA containing aliphatic polyols as core monomers were also prepared successfully. Difunctional and trifunctional core monomers usually reached a full conversion of their OH groups, while the tetra- and hexafunctional core monomers were converted only to 89%. In all these products however, a considerable amount, usually even a majority, of the polymer molecules were core free. The poly-BHPPA products prepared displayed relatively high glass transition temperatures, in the range of 84°C to 114°C, obviously due to interactions between the phenol groups and to hydrogen bridging. The thermal stability of these products was also high, with decomposition occurring near 350°C (at a heating rate of 10°C / min) Kinetics investigations of the poly-BHPPA reactivity towards isocyanates The poly-BHPPA are polyphenols and were expectedly found to react significantly slower with isocyanates than aliphatic alcohols. The reactivity of poly BHPPA was also found to be somewhat lower than that of the monofunctional, low molar-mass 4 ethylphenol. Hexamethylene diisocyanate trimer, Desmodur N3300, was found to be more reactive than hexamethylene diisocyanate (HDI) or butyl isocyanate in all experiments, possibly due to a substitution effect. The substitution effect can be explained by a change of microenvironment caused by conversion of isocyanate group and OH group into urethane groups. The reactions of low-molecular-mass alcohols or phenols with low molecular weight isocyanates followed well the 2nd order kinetics, while the reactions of poly-BHPPA with isocyanates show deviations from ideal 2nd order kinetics at higher conversions. All the kinetics experiments were carried out under catalysis by dibutyltin dilaurate. This catalyst inhibits the undesired reaction of isocyanate groups with moisture. It was also found that the catalysis was necessary to reach reasonable curing times for poly-BHPPA based polyurethane networks. The uncatalyzed systems reacted extremely slowly. Preparation of polyurethane networks from poly-BHPPA The poly BHPPA products prepared were used successfully as OH functional precursors of polyurethane networks. The networks prepared contained only very low sol fractions. Acetone and also ethylene diglycol dimethylether (diglyme) were found to be good swelling solvents for the networks prepared, while methyl propyl ketone was a much poorer solvent and aromatic compounds like toluene or xylene practically did not swell the poly BHPPA based polyurethanes. The networks prepared contain a relatively high amount of cyclic bonds, 40 to 50% in the finally cured state, which is an expected result for systems with precursors of high functionality and with small distances between the functional groups. The temperature of glass transition (Tg) of the networks prepared (ranging from 68°C to 126°C) depends of the poly BHPPA precursor used: it increases with increasing molecular mass and with increasing core functionality. The choice of the isocyanate crosslinker also influences Tg: the networks made from HDI show higher Tg values, than networks made from the same poly BHPPA but crosslinked with Desmodur N3300 (Tri HDI). The urethane bonds in the networks prepared start to decompose near 140°C. The easier degradation of PU with aromatic urethane bonds is a disadvantage in comparison with aliphatic polyurethanes, whose decomposition starts at 200°C. The surfaces of polyurethane coatings prepared are smooth, displaying a roughness of ca. 20-25 nm, and relatively hydrophilic: the contact angle with water was found to be near 80°. The prepared networks are also relatively hard, possessing the Shore D hardness of 70.
5
Wang, Kuan-Jong. « Reactive processing of polyureas and polyurethane-polyester hybrids / ». The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487670346877346.
Texte intégral
6
Wang, Xiaojiang. « Polyester Based Hybrid Organic Coatings ». University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1340906197.
Texte intégral
7
Gong, Caiguo. « Linear, Branched and Crosslinked Polymers, Polyesters, Polyurethanes and Polymethacrylates Derived From Rotaxane Formation : Syntheses and Properties ». Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/11134.
Texte intégralRésumé :
As new family of composite materials, polyrotaxanes, polymers containing rotaxane units, have interested scientists world wide in last few decades because of their new properties. Crown ethers have been widely used as the cyclic component in various polyrotaxanes. However, due to significant loss of threaded cyclic during polymerization, the driving force for threading remains unidentified.
To prevent threaded cyclics from slipping off the backbone during polycondensation, a diol blocking group (BG) and a diacid chloride BG were prepared and incorporated into polyesters as monomers or comonomers. Using these BG's effectively reduced or prevented dethreading and thus indeed increased threading efficiency (m/n, average number of cyclics per repeat unit). The study also brought about new evidences for the formation of the polyrotaxanes, i.e., the hydrolytic recovery of threaded crown ether, different chemical shift of the threaded cyclic from the free species and nuclear Overhauser effect spectroscopy (NOESY) correlation. The threading efficiencies increased with lower polymerization temperature and increasing feed ratio of the cyclic vs. diol monomer. H-bonding between the crown ether and the OH groups of the diol monomers was identified as the driving force for threading and detailed threading and dethreading mechanisms were revealed.
Co-polyurethane rotaxanes were also prepared by polymerization of diol BG, tetra(ethylene glycol) and 4,4'-methylenebis(p-phenyl isocyanate) (MDI) using 30C10 as solvent. Compared to that with the polyester backbone, dethreading was slower with the polyurethane because of H-bonding of the threaded cyclics with the in-chain NH groups. Interestingly, as proved by proton NMR spectra, the cyclics were locked at the NH sites in chloroform but pushed away from the site in DMSO. Thus these polyurethane rotaxanes were solvent switchable molecular shuttles with controlled microstructures. Based on H-bonding theory, a new method for the preparation of polyrotaxanes, a melt threading process, was demonstrated by threading "42C14" onto a preformed polyurethanes. The properties of the resulting polyurethane rotaxanes depended on threading efficiency (m/n): the higher m/n was, the lower the Tg was but the higher the intrinsic viscosity was.
Novel topological polymers, mechanically-linked branched and crosslinked poly(methyl methacrylate)s were synthesized by pendant group modification of a preformed poly(methacryloyl chloride) with 5-hydroxymethyl-1,3-phenylene-1,3-phenylene-32-crown-10 (hydroxymethyl BMP32C10). The rotaxane structure was directly proved by NOESY. The polycondensation of di(hydroxymethyl)-BMP32C10, tetra(ethylene glycol) and MDI afforded similar mechanically-linked polyurethanes. The branching points were manifested by the complexation of the polyurethane with paraquat. The polydispersities (PDI) and topologies (linear, branched and crosslinked) of these polymers were simply controlled by the polymerization conditions; this will ultimately afford polymers with different processibility (melt viscosity) and mechanical properties, e.g., the slippage of the cyclics along the backbone ensures a higher elongation.
The complexation between a preformed polymeric crown ether and paraquat afforded a novel class of main chain polyrotaxanes. The continuous titration method afforded accurate estimates of the equilibrium constant, enthalpy and entropy changes and thus polyrotaxanes with certain m/n can be simply designed. Compared to the starting polymers, polyrotaxanes had higher viscosity, higher glass transition temperature and different solubilities. A concept for the preparation of reversible branched and/or crosslinked homo- or co-polymers was invented, which was demonstrated by preparation of a reversibly branched polymer by self-assembly of a preformed polymeric crown ether and a polyurethane bearing paraquat moieties. This concept can be applied to increase the compatibility and the interfacial interaction for polymer blends and construct reversible networks.
The present work is supported by the Division of Materials Research, National Science Foundation, through individual investigator grant DMR-93-20196.Ph. D.
8
Chou, Ying-Cheng. « Structure formation and properties of polyurethane-unsaturated polyester interpenetrating polymer / ». The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487843314694815.
Texte intégral
9
Barbara, Imane. « Synthèse de polymères macroporeux par polymérisation par étape en émulsion concentrée ». Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0045/document.
Texte intégralRésumé :
Les polyHIPEs sont des matériaux cellulaires obtenus par polymérisation d’émulsions concentrées appelées HIPEs « High Internal Phase Emulsions ». La phase continue de l’émulsion contenant les monomères est le siège de la polymérisation permettant la création de la matrice solide. La phase dispersée engendre la porosité. Les matériaux polyHIPEs sont généralement synthétisés par polymérisation radicalaire. La variété des monomères utilisables est donc ainsi limitée. La majorité des polymères à haute performances étant obtenus par polycondensation, il serait d’un grand intérêt d’élargir la gamme des matériaux poreux de type polyHIPEs disponibles en utilisant cette technique. L’objectif de ce travail consiste à synthétiser des matériaux polyHIPEs obtenus par polycondensation ou polyaddition et à les caractériser. Réaliser une réaction de polymérisation par étape au sein d’une émulsion concentrée représente un vrai défi car ce type de réaction requiert généralement des conditions opératoires peu compatibles avec la stabilité des émulsions concentrées. Dans le cadre de ce travail, nous nous sommes intéressés à la synthèse de polyHIPEs de type polyuréthane et polyester. L’homogénéité de la morphologie de ces matériaux a été étudiée en faisant varier un certain nombre de paramètres tels que : la nature de l’émulsion (aqueuse ou non-aqueuse, stabilisée par des tensioactifs ou des particules), la nature des catalyseurs et les techniques de polymérisation. Ce travail a permis d’accéder pour la première fois à des matériaux polyHIPEs de type polyuréthane et polyester. Les résultats obtenus ouvrent la voie au développement dans ce domainePolyHIPEs are cellular materials obtained by polymerization within HIPEs « High Internal Phase Emulsions ». The polymerization occurs in the continuous phase of the emulsion allowing the creation of a solid matrix. The dispersed phase induces the porosity. PolyHIPEs are generally obtained by free-radical polymerization which restricts the choice of monomers. The majority of high performance polymers are obtained by polycondensation therefore it will be a great interest to enhance the variety of polyHIPEs available by using this technique. The objective of this work consists to synthetize polyHIPEs using polycondensation or polyaddition. Performing a step-growth polymerization within emulsion is a great challenge because this kind of reaction requires conditions generally incompatible with the stability of HIPEs. In the context of this work, we focused on the synthesis of polyurethane and polyester polyHIPEs. The homogeneity of the morphology of the materials was studied by varying several parameters, such: the nature of the emulsion (aqueous or non-aqueous, stabilized by surfactants or particles), the nature of the catalysts and the polymerization techniques. This work opens the access for the first time to polyurethane and polyester polyHIPEs. The results obtained are a starting point for further development in this field
10
Vitkauskienė, Irena. « Chemical recycling of industrial poly(ethylene terephthalate) waste : synthesis of aromatic polyester polyols, their properties and use ». Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110920_152312-50729.
Texte intégralRésumé :
In this study, the generation points, reasons and properties of industrial PET waste were examined in detail. Different chemical recycling ways were suggested for each kind of industrial PET waste. Under glycolysis of industrial PET waste by ethylene glycol, the yield of the main product bis(2-hidroxyethylene) terephthalate was higher than 85 %. Several series of aromatic polyester polyols (APP) were synthesized by transesterification of industrial PET waste using diethyleneglycol (DEG) in the presence of functional additives glycerol (GL) or/and adipic acid (ADA). The effect of functional additives on transesterification process and viscosity of APP was thoroughly studied and mathematically described for the first time. APP synthesized by transesterification of industrial PET waste using DEG in the presence of ADA and/or GL fragments, had lower crystallinity and were much more stable during storage at room temperature. Viscosity of APP slightly depended on the catalyst type and its concentration. Polyurethane-polyisocyanurate (PU-PIR) foams were produced under the reaction of APP and an excess of diisocyanate. PU-PIR foams based on PET-waste-derived APP containing fragments of GL or/and ADA were characterized by excellent physical-mechanical properties, high thermal stability, low heat release and smoke production. The burning test confirmed that PU-PIR foams satisfied the requirements for class E of construction products and building elements.Šiame darbe nuodugniai ištirtos gamybinių polietilentereftalato (PET) atliekų susidarymo vietos, priežastys bei jų savybės. Pasiūlyti skirtingi cheminio perdirbimo būdai ir sąlygos kiekvienai gamybinių PET atliekų rūšiai. Vykdant gamybinių PET atliekų glikolizę etilenglikoliu, pasiekta didesnė negu 85 % bis(2-hidroksietilen)tereftalatо išeiga. Peresterinant gamybines PET atliekas dietilenglikoliu (DEG) ir naudojant funkcinius priedus glicerolį (GL) ir/arba adipo rūgštį (ADR), susintetinta serija aromatinių poliesterpoliolių (APP), besiskiriančių savo klampa ir kitomis savybėmis. Pirmą kartą nuodugniai ištirta ir matematiškai aprašyta peresterinimo reakcijos mišinyje esančių funkcinių priedų įtaka APP klampai. APP, susintetinti peresterinant gamybines PET atliekas DEG ir turintys ADR ir/arba GL fragmentų, yra mažai linkę kristalintis ir stabilūs saugant juos kambario temperatūroje. APP klampa mažai priklauso nuo metaloorganinio katalizatoriaus cheminės sudėties ir jo koncentracijos. Naudojant PET peresterinimo metu gautus APP ir diizocianato perteklių, susintetintos poliuretano-poliizocianurato (PU-PIR) putos. Putos, gautos iš APP, kuriuose yra GL ir/arba ADR fragmentų, pasižymi geromis fizikomechaninėmis savybėmis ir dideliu terminiu stabilumu, joms degant išsiskiria mažesnis šilumos ir dūmų kiekis. Atliekant degumo bandymus nustatyta, kad PU-PIR putos atitinka reikalavimus, taikomus Е klasės statybinėms konstrukcijoms ir elementams.
11
Unal, Serkan. « Synthesis and Characterization of Branched Macromolecules for High Performance Elastomers, Fibers, and Films ». Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/29783.
Texte intégralRésumé :
An A2 + B3 polymerization for the synthesis of hyperbranched polymers was altered using oligomeric precursors in place of either one or both of the monomer pairs to synthesize highly branched macromolecules. Unique topologies that are intermediates between long-chain branched and hyperbranched structures were obtained and the term "highly branched" was used to define these novel architectures. Various types of highly branched polymers, such as polyurethanes, poly(urethane urea)s, poly(ether ester)s, and poly(arylene ether)s were synthesized using the oligomeric A2 + B3 strategy. The molar mass of the oligomeric precursor permitted the control of the molar mass between branch points, which led to interesting macromolecular properties, such as superior mechanical performance to conventional hyperbranched polymers, disrupted crystallinity, improved processibility, and a multitude of functional end groups.
Highly branched poly(urethane urea)s and polyurethanes exhibited microphase-separated morphologies as denoted by dynamic mechanical analysis. The similarity in soft segment glass transition behavior and mechanical properties of the branched systems with that of the linear analogues suggested these materials have considerable promise for a variety of applications. When a polycaprolactone triol was utilized as the B3 oligomer for the synthesis of highly branched polyurethane elastomers, the high degree of branching resulted in a completely amorphous soft segment, whereas the linear analogue with equivalent soft segment molar mass retained the crystallinity of polycaprolactone segment.
Oligomeric A2 + B3 methodology was further utilized to tailor the degree of branching of poly(ether ester)s that were developed based on slow addition of dilute solution of poly(ethylene glycol) (PEG) (A2) to a dilute solution of 1,3,5-benzenetricarbonyl trichloride (B3) at room temperature in the presence of triethylamine. A revised definition of the degree of branching was proposed to accurately describe the branched poly(ether ester)s and the degree of branching decreased as the molar mass of the PEG diols was increased. Moreover, branched poly(arylene ether)s were prepared via a similar oligomeric A2 + B3 polymerization of phenol endcapped telechelic poly(arylene ether sulfone) oligomers (A2) and tris(4-fluorophenyl) phosphine oxide (B3) in solution. Highly branched poly(ether ester)s were also synthesized in the melt phase using the oligomeric A2 + B3 polymerization strategy. Melt polymerization effectively limited the cyclization reactions, which are common in A2 + B3 polymerizations in solution, and overcame the need for large amounts of polymerization solvent typical of A2 + B3 systems.
Finally, a new family of telechelic polyester ionomers was synthesized based on phosphonium bromide salt end groups and branching allowed the incorporation of higher levels of ionic end groups compared to linear analogues.Ph. D.
12
Hancock, Amber Nicole. « A Comparison of the Degradation of Mold and Mold-like Fungi on Defined Synthetic Thermoset Polyadipate Polyurethane Coatings ». University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1589715689044313.
Texte intégral
13
Garbin, Daniel Fernando. « Efeito do material da face nas propriedades mecânicas de painéis sanduíche para aplicação rodoviária ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/157831.
Texte intégralRésumé :
Painéis sanduíche são largamente utilizadas em diversas aplicações de engenharia e o estudo de suas propriedades é fundamental para a ampliação de sua utilização. Neste trabalho, foram estudados painéis sanduíche com núcleo de poliuretano e faces de fibra de vidro fabricados pelo processo de laminação contínua. Na primeira configuração, as faces do painel foram fabricadas com manta de fibra de vidro e resina poliéster, com 39% de teor de vidro em massa e espessura de 1,9 mm. Na segunda configuração, as faces do painel foram fabricadas com tecido de fibra de vidro e resina poliéster, com 54% de teor de vidro em massa e espessura de 1,2 mm. Realizou-se o cálculo das propriedades mecânicas de cada compósito no programa MECH-Gcomp. As propriedades do núcleo foram retiradas, inicialmente, da literatura. Então, foi possível realizar a avaliação dos painéis pelo método dos elementos finitos utilizando elementos sólidos, comparando o comportamento dos dois tipos de painéis em relação aos carregamentos de compressão de núcleo, de compressão longitudinal e de flexão. Foram realizados ensaios nas faces isoladas e também nos painéis sanduíche completos. Para as faces, os ensaios foram de teor mássico de fibra de vidro, tração, compressão e cisalhamento Iosipescu, conforme as normas ASTM D5630, D3039/D3039M, D6641/D6641M e D7078/D7078M, respectivamente. Já para os painéis sanduíche, foram realizados os ensaios de compressão de núcleo, compressão longitudinal (edgewise) e cisalhamento do núcleo utilizando flexão, conforme as normas ASTM C365/C365M, C364/C364M e C393/C393M, respectivamente. Após os ensaios, foram calibrados os modelos do MEF, permitindo que os mesmos possam calcular outras configurações similares de painel sanduíche. Foi utilizado o programa Autodesk Simulation Composite Design para realizar a validação do ensaio de cisalhamento do núcleo. Concluiu-se que a análise de elementos finitos foi confiável em representar de forma realista o comportamento dos painéis sanduíche e a redução na espessura das faces do painel pode ser compensada com o aumento da sua resistência mecânica e rigidez por meio do aumento no teor mássico de reforço e trabalhando com a orientação do mesmo.Sandwich panels are widely used in a variety of engineering applications and the study of their properties is fundamental for the expansion of their use. In this work, we studied sandwich panels with polyurethane core and fiberglass faces manufactured by the continuous lamination process. In the first configuration, the panel faces were made of fiberglass and polyester resin, with 39% glass content by mass and 1.9 mm thickness. In the second configuration, the panel faces were fabricated from fiberglass fabric and polyester resin, with 54% glass content by mass and 1.2 mm thickness. The mechanical properties of each composite were calculated in the MECH-Gcomp software. The properties of the core were initially taken from the literature. Then, it was possible to evaluate the panels by the finite element method using solid elements, comparing the behavior of the two types of panels in relation to the core compression loads, edgewise compression and bending. Tests were performed on the faces and also on the complete sandwich panels. For the faces, the tests were fiberglass mass content, tensile, compression and Iosipescu shear, according to ASTM D5630, D3039/D3039M, D6641/D6641M and D7078/D7078M, respectively. For sandwich panels, core compression, edgewise compression and core shear using bending tests were performed according to ASTM C365/C365M, C364/C364M and C393/C393M, respectively. After the tests, the FEM models were calibrated, allowing them to calculate other similar sandwich panel configurations. It was used Autodesk Simulation Composite Design software to validate the core shear test. It was concluded that the analysis of finite elements was reliable in realistically representing the behavior of the sandwich panels and the reduction in the thickness of the panel faces can be compensated with the increase of its mechanical resistance and stiffness by increasing the mass content of reinforcement and working with the orientation of the same.
14
Ziemer, Antje. « Hochverzweigte Polyesterole und deren Abmischungen für den Einsatz in Polyurethan-Schaumstoffen ». [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968388019.
Texte intégral
15
Ziemer, Antje. « Hochverzweigte Polyesterole und deren Abmischungen für den Einsatz in Polyurethan-Schaumstoffen ». Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2003. http://nbn-resolving.de/urn:nbn:de:swb:14-1055234737562-37907.
Texte intégralRésumé :
Auf Grundlage der beiden Monomere (2,2-Bis(hydroxymethyl)propansäure (1) und 4,4-Bis(4-hydroxyphenyl)valeriansäure (2)) wurden hochverzweigte Polyester synthetisiert. Durch Verwendung von zwei-, drei-, vier- und sechsfunktionalen Kernmolekülen konnte die strukturelle Vielfalt der hochverzweigten Polyester erhöht werden. Abmischungen auf der Grundlage zweier Polyole (Polyether- bzw. Esterdiol) mit verschiedenen hochverzweigten Polyestern wurden hinsichtlich ihrer Mischbarkeit mittels DSC- und DMA-Messungen sowie rheologisch, mittels temperaturabhängiger IR-Spektroskopie, hinsichtlich ihrer Oberflächenspannung und mittels temperaturabhängiger AFM-Messungen bzw. SAXS-Messungen charakterisiert. DSC und DMA-Messungen des Glasübergangszustandes der Abmischungen gaben Hinweise, dass hochverzweigte Polyester unterschiedlicher Strukturen mit den Polyolen auf molekularer Ebene mischbar sind. Die hochverzweigten Polyester P1 und P1-PEG400 verbesserten die Verarbeitungseigenschaften eines geschlossenzelligen PU-Hartschaumstoffes. Durch die Hochfunktionalität der hochverzweigten Polyester erfolgte das Aushärten des Schaumstoffes schneller, wobei überraschenderweise das "Fließen" des Schaumstoffes gleichzeitig verbessert werden konnte. Durch den Zusatz der genannten hochverzweigten Polyester zu dem Polyetherpolyol konnte die Viskosität gesenkt werden, was die Fließeigenschaften des Schaumstoffes verbessert. Die Schaumstoffe zeigen weiterhin verbesserte mechanische Eigenschaften.
16
Liu, Xiaohong. « Synthesis and Characterization of Carbohydrate-conjugated Polyesters and Polyurethanes ». University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1491433530882435.
Texte intégral
17
Yang, Shaoguang. « Design and Investigation of Polyurethane End-Capped Polyesters with Controlled Hydrolytic Stability ». University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1407971721.
Texte intégral
18
Zhang, Musan. « Advancing Step-Growth Polymers : Novel Macromolecular Design and Electrostatic Interactions in Polyesters and Polyurethanes ». Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/23239.
Texte intégralRésumé :
Conventional melt transesterification successfully synthesized high molecular weight segmented copolyesters. The cycloaliphatic monomers 2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO) and dimethyl-1,4-cyclohexane dicarboxylate (DMCD) afforded sterically hindered, ester carbonyls in high-Tg polyester precursors. Reaction between the polyester polyol precursor and a primary or secondary alcohol at melt polymerization temperatures revealed reduced transesterification of the polyester hard segment as a result of enhanced steric hindrance adjacent to the ester linkages. Subsequent polymerization of a 4,000 g/mol polyol with monomers comprising the low-Tg block yielded high molecular weight polymers that exhibited enhanced mechanical properties compared to a non-segmented copolyester control. Atomic force microscopy uncovered unique needle-like, interconnected, microphase separated surface morphologies, and small-angle X-ray scattering confirmed the presence of bulk microphase separation.
This new synthetic strategy enabled selective control of ionic charge placement into the hard segment or soft segment block of segmented copolyesters using melt transesterification. The ionic placement impacted the microphase-separated morphology, which influenced its thermomechanical properties and resulting mechanical performance. Melt transesterification of low-Tg, sodium sulfonated copolyesters achieved up to 15 mol% ionic content. The 10 and 15 mol% sodium sulfonated copolyesters exhibited water-dispersibility, which enabled cation dialysis exchanges to divalent metal cations. The sulfonated copolyesters containing divalent metal cations exhibited enhanced rubbery plateau moduli to higher temperatures.
Novel trialkylphosphonium ionic liquids chain extenders enabled the successful synthesis of poly(ethylene glycol)-based, cationic polyurethanes with pendant phosphoniums in the hard segments (HS). Aqueous size exclusion chromatography (SEC) confirmed the charged polyurethanes, which varied the phosphonium alkyl substituent length (ethyl and butyl) and cationic HS content (25, 50, 75 mol%), achieved high absolute molecular weights. Dynamic mechanical analysis (DMA) demonstrated the triethylphosphonium (TEP) and tributylphosphonium (TBP) polyurethanes displayed similar thermomechanical properties, including increased rubbery plateau moduli and flow temperatures. Fourier transform infrared spectroscopy (FTIR) emphasized the significance of ion-dipole interaction on hydrogen bonding. Atomic force microscopy (AFM), small-angle X-ray scattering (SAXS), and wide-angle X-ray diffraction (WAXD) supported microphase separated morphologies in the trialkylphosphonium polyurethanes, despite the presence of ionic interactions. Sorption isotherm experiments revealed TBP polyurethanes displayed similar water sorption profiles to the noncharged analogue and lower water absorptivity compared to TEP. The phosphonium polyurethanes displayed significantly improved tensile strain; however, lower tensile stress of the TEP polyurethane was presumably due to absorbed water. In addition, we also explored applications of the trialkylphosphonium polyurethanes as nucleic acid delivery vectors and demonstrated their abilities to form colloidally stable polyplexes in salt-containing media.Ph. D.
19
Chang, Zhengmian. « Synthesis and Properties of Novel Triptycene-containing Segmented Polyurethanes and Semicrystalline Polysulfone-polyester Multiblock Copolymers ». Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/73294.
Texte intégralRésumé :
Segmented copolymers are important polymers with attractive properties and wide applications. In this dissertation, segmented polyurethanes containing triptycene units and multiblock copolymers containing poly(arylene ether sulfone) (PAES) and poly(1,4-cyclohexyldimethylene terephthalate) (PCT) segments were synthesized and systematically studied.
Investigation of the influence of the bulky triptycene structure on the morphologies and properties of segmented polyurethanes was carried out by using triptycene-1,4-hydroquinone bis(2-hydroxyethyl)ether (TD) as the chain extender. Segmented polyurethanes based on poly(tetramethylene glycol) (PTMG) of 1000 g/mol were synthesized using a two-step polymerization procedure. Hydroquinone bis(2-hydroxyethyl)ether (HQEE) was used for the purpose of comparison. Hard segments with different bulkiness and flexibility were prepared with hexamethylene diisocyanate (HDI) and 4,4'-methylenebis(phenyl isocyanate) (MDI), and HQEE or TD as chain extenders. The incorporation of bulky TD and less flexible MDI significantly inhibited hydrogen bonding based on the Fourier transform infrared (FTIR) results. In addition, the microphase separation was also disturbed by the bulky and less flexible hard segments with confirmation from tapping mode atomic force microscopy (AFM) and small angle X-ray scattering (SAXS). The flexible HDI can be used to overcome the bulkiness of triptycene, promote microphase separation, and enhance mechanical properties.
Novel PTMG based soft segments containing triptycene units were also prepared with number average molecular weight (Mn) around 2500 g/mol. Then this soft segment was reacted with MDI and HQEE to prepare segmented polyurethanes. Soft segments such as hydroquinone (HQ) containing PTMG (Mn = 2100 g/mol), and pure PTMGs (Mn = 1000 and 2000 g/mol) were used for comparison. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) results demonstrated that triptycene units led to an increased glass transition temperature (Tg) and an elimination of the crystallization of the soft segments. The absence of strain hardening for the triptycene-containing sample suggested a suppressed strain induced crystallization of soft segments, which was also confirmed by the analysis of wide-angle X-ray diffraction (WAXD) on the films strained to 370 %.
Crystallizable PCT segments were copolymerized with PAESs to enhance solvent resistance and mechanical properties. PAES oligomers (Mn = 2000 g/mol) were first synthesized, and then reacted with dimethyl terephthalate (DMT) and 1,4-cyclohexanedimethanol (CHDM). Weight percentages of PCT segments were gradually changed from 20 wt% to 80 wt%. With PCT content greater than 50 wt%, crystallinity was observed by DSC, DMA, and WAXD. The extent of crystallinity of the copolymers was dependent on the wt% of PCT. Furthermore, crystallization behavior of copolymers based on two CHDMs with different isomer ratios (cis/trans 30/70 and all trans) were studied. Due to their more symmetric structure, copolymers based on all trans CHDM exhibited a higher extent of crystallization.Ph. D.
20
Atter, Kieran Timothy. « Syntheses and ROMP of norbornene-functionalised polyesters and polyurethanes and evaluation of their products ». Thesis, Durham University, 2018. http://etheses.dur.ac.uk/12612/.
Texte intégralRésumé :
The aim of this project is to develop a polymer system which: 1) incorporates one or more norbornene rings in the pre-polymer; 2) can be polymerised using ROMP to yield linear or cross-linked polymers; 3) utilises little, or no, styrene; 4) produces products with comparable properties to current unsaturated polyester resins; 5) can polymerise in solvent, or in the presence of a reactive diluent; 6) is as environmentally friendly as possible; and 7) is as cost-effective as possible. Chapter 1 contains a history of olefin metathesis, ROMP, and ROMP catalysts. Using ROMP to polymerise norbornene-containing monomers is also included, as well as the synthesis of random and block-copolymers using ROMP. In Chapter 2, norbornene-containing polyesters – synthesised at Scott Bader – are characterised using 1H and 13C NMR spectroscopy, and SEC. The syntheses of hexamethylene-1,6-bis(5-norbornene-2-methoxy tetraethylene glycol carbamate) (DFM1); 2-hydroxyethyl-5-norbornene-2-carboxylate (HE-NBE-CO2); hexamethylene-1,6-bis(5-norbornene-2-carboxylate-2-ethoxy carbamate) (DFM2); and 2-hydroxyethyl-5-norbornene-2-carboxylate butyl carbamate (MFM) are all reported, and confirmed by characterisation using 1H and 13C NMR spectroscopy and ASAP mass spectrometry. Chapter 3 details the polymerisation of N-2-ethylhexyl norbornene dicarboximide (EHNBEDC) using Grubbs 1st generation (G1); 2nd generation (G2); and modified 2nd generation (MG2) catalysts; and analyses thereof. As well as this, Polyesters 1 and 2 are shown to undergo ROMP with all three catalysts and cross-link to form a gelled polymer. The gel contents and gel time of which was measured. Finally, Polyesters 1 and 2 are copolymerised with EHNEBDC using the three catalysts and shown to increase the gel contents with increasing concentration of the polyester. In Chapter 4, styrene is added to the reaction mixture for the ROMP of Polyesters 1 and 2. Increasing the level of styrene up to 2 equivalents with respect to the initiator is shown to have no effect on the gel contents with any of G1, G2 or MG2. However, the gel time can be increased by increasing the styrene up to 5 equivalents with respect to G1 or G2; though there is no increase in gel time observed when using styrene with MG2. Chapter 5 shows that MFM, DFM1 and DFM2 can be polymerised using ROMP with G1, G2 and MG2. The ROMP of MFM produces a linear polymer which can be characterised using 1H and 13C NMR spectroscopy, as well as SEC. DFM1 and DFM2 produce cross-linked polymers when they undergo ROMP. MFM can produce a block copolymer with EHNBEDC when using G1 as the initiator. Random and block copolymers of HE-NBE-CO2 and MFM are also formed using varying levels of each monomer. Some of the copolymer systems are tested using Dynamic Mechanical and Thermal Analysis (DMTA): measuring their Tg’s and storage moduli. In-mould bulk copolymers, using MG2 as the initiator, are achievable in several copolymer systems. Any trends in the Tg, or storage modulus, are investigated for each system. Finally, Chapter 6 offers conclusions to the work undertaken and some possible future work to further understand the polyesters and polyurethanes and their ROMP products, as well as the possibility of increasing the library of polyesters and polyurethanes using differing starting materials.
21
Talamoni, João Roberto. « Sintese, caracterização e biodegradação de um poliester-uretano ». [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267448.
Texte intégralRésumé :
Orientador: Lucia Helena Innocentini MeiDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
Made available in DSpace on 2018-08-03T19:31:20Z (GMT). No. of bitstreams: 1 Talamoni_JoaoRoberto_M.pdf: 3179199 bytes, checksum: 8fe9d391161838e5f0a3bd3360ef2652 (MD5) Previous issue date: 2003
Resumo: Anualmente, são produzidas cerca de 110 milhões de toneladas de plásticos no mundo, e pelo menos a metade desta quantidade é rapidamente descartada sem qualquer cuidado, permanecendo em aterros e na natureza por décadas, gerando um custo ambiental muito alto. Na tentativa de minimizar este problema, muitos cientistas passaram a investir em pesquisas na tentativa de descobrir materiais que substituam estes plásticos e que ao mesmo tempo sejam ambientalmente amigáveis, ou seja, quando em contato com o solo e em ambientes propícios, estes novos materiais se degradem rapidamente. Muitas linhas de pesquisas trabalham com polímeros de origem natural, outras com síntese microbiológica, porém, uma das linhas de pesquisas mais forte neste sentido é a síntese e modificação de poliésteres alifáticos, que sabidamente possuem boas propriedades de biodegradação. Assim, o objetivo deste trabalho foi sintetizar, caracterizar e modificar um poliéster alifático com boas propriedades de biodegradação. Partiu-se de monômeros conhecidos, como o ácido adípico e o monoetileno glicol, e ainda usou-se outros materiais para tentar melhorar as propriedades dos polímeros sintetizados, como o glicerol e o diisocianato de hexametileno, este último usado para se obter poliésteres-uretanos de massa molar maior, menor cristalinidade e de mais fácil biodegradação. Todas as amostras obtidas foram caracterizadas via medições de suas massas molares por Cromatografia por Permeação em Gel e Viscosidade Intrínseca, e ainda mediuse a efetividade das reações através da Espectroscopia por Infravermelho. Também determinou-se as temperaturas de cristalização e de fusão através da Calorimetria Diferencial Exploratória e a perda de massa através de Análise Termogravimétrica. Ainda, acompanhou-se o processo de biodegradação através de fotos e microscopia ótica. Os resultados obtidos neste trabalho mostraram que a síntese de poliésteres alifáticos requer muitos cuidados para que se obtenha materiais com boas propriedades de aplicação, e que as modificações via isocianato, obtendo-se poliésteres-uretanos, é um caminho bastante interessante para a melhoria destas propriedades, e ainda, pode-se concluir que a síntese destes materiais é bastante promissora para se obter materiais
Abstract: Annually, about 110 millions of tons of plastics are produced around the world, and at least haIf of this amount is wasted speciaIly in landfills, remaining there for decades, causing high1y environmental costs. In order to solve this problem, many scientists are performing researches trying to create new materiaIs with adequate properties to replace these plastics and at the same time, materiaIs that are environmentally mends, and can be degraded when in contact with soil and under adequate conditions. Many researchers are working with natural polymers, others with polymers synthesized through microbiologicaI conditions, and others are working with the synthesis and modification of aIiphatic polyesters, which are known since decades that they are good biodegradable materiaIs. The objective of this work is the synthesis, characterization and modification of aIiphatic polyesters with good biodegradable properties. It was used known monomers for the synthesis, like adipic acid and ethylene glycol, and others materiaIs to improve properties, like glycerol and hexamethylene diisocyanate, this last one was used to obtain a polyester-urethane, with high molecular weight and lower degree of crystallization, improving its ability to degrade. All samples synthesized were characterized by Gel Permeation Chromatography and Intrinsic Viscosity to measure their molecular weight, and the effectiveness of the reactions were followed by Fourier-Transform Infrared Spectroscopy. Melting and Glass Transition temperatures and Crystallization behavior were measured through Differential Scanning Calorimetry. Using Thermogravimetry measurements, the loss of mass of all samples with temperature was measured. The biodegradation process was followed by periodical photos and with Optical Microscopy. The final results showed that the synthesis of aliphatic polyesters need to be carefully carried out to achieve materials with good properties, and the extension of these aliphatic polyesters with isocyanates is a viable way to increase properties of these materials, but it is possible to conc1ude that the synthesis of such materials is a very promising field to have biodegradable materials
Mestrado
Ciencia e Tecnologia de Materiais
Mestre em Engenharia Química
22
Ferreira, Adriane de Medeiros. « Homopolímeros e copolímeros furânicos termorreversíveis ». Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18158/tde-06052016-090006/.
Texte intégralRésumé :
Na presente tese foram preparados poliésteres derivados de dois materiais renováveis o ácido 2,5-furanodicarboxílico (AFD) e a isoidida. Foram também preparados monômeros dihidroxílados para uso em poliesterificações e em reações com diisocianatos contendo um aduto de Diels-Alder (DA) formado pela reação de um grupo furano e uma maleimida (reação entre uma bismaleimida e o álcool furfurílico). Esses diois foram utilizados na preparação de poliésteres e poliuretanos termorreversíveis. A termorreversibilidade dos materiais preparados advém do fato de que os adutos de DA são termorreversíveis (rDA). Portanto, ao aquecer os poliésteres preparados com aduto-DA são originados monômeros difuncionais com grupos furano e/ou maleimida. O produto da rDA pode então ser repolimerizado, mas não via reações de poliesterificação ou isocianato/hidroxila, mas pelo acoplamento furano/maleimida (DA). Por fim uma nova rota para a obtenção de copolímeros aleatórios foi investigada. Essa rota consiste em provocar a rDA de uma mistura de dois homopolímeros distintos obtidos por polimerização em etapas contendo no interior de suas unidades repetitivas adutos de Diels-Alder e em seguida provocar a sua repolimerização via DA para dar origem a um copolímero aleatório. Os materiais foram caracterizados por suas estruturas químicas por Espectroscopia na região do infravermelho com transformada de Fourier (FTIR), ressonância magnética nuclear de próton (RMN ¹H). Foram feitos ensaios de cromatografia de permeação de gel (GPC), onde notou-se uma massa média numérica e ponderal para os poliésteres obtidos a partir do AFD e também para o poliéster e poliuretano termorreversíveis de aproximadamente 1600 g.mol¹. Nos ensaios de calorimetria exploratória diferencial (DSC) foi obtido Tgs variados para os poliésteres obtidos a partir do AFD indo de 88 a 159ºC, de 80ºC para o poliuretano termorreversível e de 106ºC para o poliéster termorreversível. Para a análise termogravimétrica (TGA) foi observado temperaturas de degradação para os poliésteres obtidos a partir do AFD em torno de 280ºC. Para a análise térmica dinâmico-mecânicas (DMTA) obteve-se Tg\'s em 117, 123 e 120ºC para o poliéster, o poliuretano e o copolímero termorreversíveis.In this thesis it was prepared polyesters of two renewable monomers, the 2.5-furandicarboxylic acid and isoidide. Dihydroxy monomers were also prepared for use in polysterification and in reactions with diisocyanates, both containing Diels-Alder adduct in the molecule formed by the reaction of a furan group and a maleimide (reaction between bismaleimide and furfuryl alcohol). These diols were used in the preparation of thermoreversible polyesters and polyurethanes. The thermoreversibility of these materials comes from the fact that the DA adducts are thermoreversible (rDA). Therefore, heating these polymers give rise to difunctional monomers with an adduct-DA with furan and/or maleimide functions. The product of the rDA may then be polymerized not via polysterification reactions or isocyanate/hydroxyl, but by furan/maleimide coupling (DA) restoring the DA adduct. Finaly a new route to obtain random copolymers was investigated. This route consists in the rDA of a mixture of two different homopolymers obtained by polymerization in stages containing adducts producing monomers with furan and maleimide functions that can be polymerization via DA reaction to give a random copolymer. The materials were characterized by their chemical structures by infrared spectroscopy (FTIR), nuclear magnetic resonance of proton (¹H-NMR), gel permeation chromatography (GPC), experiments were made, where it was noticed a number and weight average mass for the polyesters obtained from the AFD and also for the thermoreversible polyester and polyurethane 1600 gmol¹. In differential scanning calorimetry tests (DSC) was obtained Tg\'s for various polyesters obtained from the AFD ranging from 88 to 159°C, 80°C for the thermoreversible polyurethane and 106°C for the thermoreversible polyester. For the thermogravimetric analysis (TGA) was observed degradation temperatures for the polyesters obtained from the AFD around 280°C. For dynamic mechanical thermal analysis (DMTA) Tg was obtained in 117, 123 and 120°C for polyester, polyurethane and copolymer thermoreversible.
23
Gremmels, Jürgen [Verfasser], et Josef [Akademischer Betreuer] Karger-Kocsis. « Partieller hygrothermischer Abbau von Polyester-Polyurethan und dessen Anwendung - ein Beitrag zur Entwicklung eines neuen Recyclingverfahrens / Jürgen Gremmels ; Betreuer : Josef Karger-Kocsis ». Kaiserslautern : Technische Universität Kaiserslautern, 2019. http://d-nb.info/1197055371/34.
Texte intégral
24
Ruiz, Villán Lorena. « Valorización del aceite de ricino en química de polímeros : Síntesis de poliésteres y poliuretanos a partir de heptanal ». Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/461094.
Texte intégralRésumé :
En la actualitat, els poliuretans i els polièsters són dos dels materials polimèrics més importants ia que se poden utilitzar en multitud de camps donada la seva versatilitat. Els últims avenços en la investigació sobre aquest tipus de polímers venen donats per la creixent demanda de processos més sostenibles i l'ús de matèries primeras d'origen renovable. Algunes d'aquestes són els olis vegetals, com l'oli de ricí el qual no és apte per el consum humà. A partir d'aquest oli, s'obté l'àcid ricinoleic amb un rendiment elevat. Aquest àcid es converteix mitjançant piròlisi en àcid undecenoic i heptanal. L'àcid undecenoic ha estat àmpliament utilitzat per a la síntesi de diferents monòmers i polímers amb elevats rendiments i sostenibilitat química. En canvi el heptanal, apreciat per les qualitats olfactives d'alguns dels seus derivats, és àmpliament utilitzat com un intermediari de síntesi per a la indústria de fragàncies i aromes. Malgrat l'ús d'aquest compost com a producte intermedi químic en la química de polímers és pràcticament inexistent.
En la present tesi s'ha investigat una àmplia varietat de transformacions químiques per obtenir monòmers bifuncionals i renovables així com els seus polièsters i poliuretans, utilitzant heptanal com a matèria primera. Tanmateix, s'han desenvolupat diferents nanosistemes basats en aquests polímers com són micel·les o nanocàpsules. Com a conclusió general, s'ha demostrat que la transformació de l'heptanal en monòmers i polimers mitjançant processos mediambientalment compatibles és una alternativa sostenible en química de polimers.En la actualidad, los poliuretanos y los poliésteres son dos de los materiales poliméricos más importantes ya a que se pueden utilizar en multitud de areas debido a su versatilidad. Los últimos avances en la investigación sobre este tipo de polímeros son impulsados por la creciente demanda de procesos más sostenibles y el uso de materias primas renovables. Algunas de estas materias primas renovables son los aceites vegetales, como el aceite de ricino el cual no es comestible. A partir de este aceite, se obtiene el ácido ricinoleico con un alto rendimiento. Este ácido se convierte mediante pirólisis en ácido undecenoico y heptanal. El ácido undecienoico ha sido ampliamente utilizado para la síntesis de diferentes monómeros y polímeros con elevados rendimientos y sostenibilidad química. En cambio el heptanal, apreciado por las cualidades olfativas de algunos de sus derivados, es ampliamente utilizado como un intermediario de síntesis para la industria de fragancias y aromas. Sin embargo, el uso de este compuesto como producto intermedio químico en la química de polímeros es prácticamente inexistente. En esta tesis se ha investigado una amplia variedad de transformaciones químicas para obtener monómeros bifuncionales y renovables así como sus poliésteres y poliuretanos, utilizando heptanal como materia prima. Además, se desarrollaron diferentes nanosistemas basados en estos polímeros como son micelas o nanocápsulas. Como conclusión general, se ha demostrado que la transformación de heptanal en monómeros y polimeros mediante procesos mediambientalmente compatibles es una alternativa sostenible en química de polimeros.
Nowadays, polyurethanes and polyesters are two of the most important polymeric materials that can be used in different applications due to their versatility. The recents advances in the research of these kinds of polymers are driven by the growing demand for greener processes and the use of renewable raw materials. Some of these renewable raw materials are vegetable oils, such as non-edible castor oil. From this oil, ricinoleic acid is obtained in a high yield. Ricinoleic acid is converted by chemical thermal cracking process into undecenoic acid and heptanal. Undecenoic acid has been widely used for the synthesis of different monomers and polymers combining high performance and sustainability. Heptanal, appreciated for the olfactory qualities of certain of its derivatives, is widely used as a synthesis intermediate for fragrance and aroma industry. However, the use of C7 cut of castor oil thermal cracking as a chemical intermediate in polymer chemistry is practically non-existent. In this thesis, we have explored a wide variety of chemical transformations to obtain bifunctional biobased monomers and their polyesters and polyurethanes, using heptanal such as raw material. Furthermore, the development a novel nanoparticles with some of these materials was carried out. As a general conclusion, the transformation of heptanal into monomers and polymers using environmentally friendly procedures has been shown to be a sustainable alternative in polymer chemistry.
25
Hölting, Dorothee [Verfasser]. « Kohlenstoffdioxid sowie 2,3-Butylenoxid-Derivate als Polymerbausteine -Synthese und Charakterisierung von Polyolen und ungesättigten Polyestern als Komponenten für Polyurethane und UP-Harze- / Dorothee Hölting ». München : Verlag Dr. Hut, 2013. http://d-nb.info/1036345580/34.
Texte intégral
26
Ramirez-Huerta, Mayela Cristina. « Steric and Anchimeric Effects on the Hydrolysis of Oligoesters and their Influence on End-Use Polyurethane Coatings ». University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1258662846.
Texte intégral
27
Nikam, Shantanu P. « RATIONAL DESIGN AND SYNTHESIS OF FUNCTIONAL POLYMERS FOR ANTIMICROBIAL, ANTI-FOULING AND ANTI-ADHESIVE BIOMATERIAL APPLICATIONS ». University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1620215379000849.
Texte intégral
28
Anderson, Emily Baird. « Synthesis and Non-Covalent Interactions of Novel Phosphonium-Containing Polymers ». Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/28849.
Texte intégralRésumé :
Phosphonium ions readily compare to ammonium ions in regards to their aggregate characteristics, thermal stability, and antibacterial activity. Ionic aggregation in phosphonium-based polymers provides thermoreversible crosslinks, ideal for reversible self-assembly, self-healing, and smart response. In polymers, these ionic functionalities aggregate, providing improved moduli, and altering the size and structure of ionic aggregates regulates polymer melt processability.
This dissertation highlights phosphonium-based chemistry for the synthesis of novel step-growth ionomers and structure-property relationships in ionic polymers. The synthesis of phosphonium endcapping reagents for melt polyester reactions afforded a thermally stable ionic functionality that controlled molecular weight. Weak association was present with phosphonium ions at low ion concentrations below 7.7 mole %. The use of novel ionic bisacetoacetate monomers in the formation of networks from Michael addition reactions led to the synthesis of ionic networks with increased and broadened glass transitions and improved tensile stresses at break and strains at break compared to those in the non-ionic networks. The first electrospun fibers from Michael addition crosslinking reactions are reported, and equilibrium ionic liquid uptake experimental results indicated that ionic functional networks absorb close to three times the amount of ionic liquid as non-ionic, poly(ethylene glycol)-based films. Chain-extending polyurethanes with a phosphonium diol and subsequently varying the hard segment content led to changes in ionic aggregation, crystallinity, and thermal transitions in the polymers. Additionally, novel phosphonium-based methacrylate monomers incorporated into diblock copolymers with styrene exhibited microphase separation. Overall, the inclusion of phosphonium ions pendant to or in the main chain of various types of polymers led to changes in morphology, improved tensile properties, enhanced moduli, broadened transitions, changes in crystalline melting points, changes in solubility, and appearance of ionic aggregation.Ph. D.
29
Leadbitter, J. « Structure-property relationships in reaction injection moulded polymers and polymer composites : Structure-property studies of reaction injection moulded polyurethanes, polyesters, polyacrylates and novel acrylic-urethane blends and of composites of these ». Thesis, University of Bradford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384311.
Texte intégral
30
Brocas, Anne-Laure. « Polymérisation anionique des époxydes par activation du monomère : monomères renouvelables et polymères fonctionnalisés ». Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14409/document.
Texte intégralRésumé :
La polymérisation anionique par activation du monomère permet d’accéder à une large gamme de polyéthers en utilisant un système amorçant à base d’un nucléophile associé au triisobutylaluminium. Cette voie a permis d’accéder à des chaînes polyéthers fonctionnalisées par des groupements hydroxyle à chaque extrémité. La (co)polymérisation de l’éther allylglycidique avec d’autres éthers cycliques a été réalisée puis les (co)polymères correspondants ont été post-fonctionnalisés pour introduire en particulier des fonctions cyclo-carbonate destinées à réagir avec des amines pour générer des fonctions hydroxyuréthane et ainsi préparer des matériaux type polyuréthane par une chimie sans isocyanate. Enfin des dérivés du pin, de la famille des acides résiniques, ont été modifiés chimiquement pour élaborer des matériaux de type résine époxyde et polyuréthane sans isocyanate. La polymérisation anionique par activation du monomère a également pu être réalisée sur un monomère époxydé issu de cette ressourceMonomer-activated anionic polymerization allows the obtention of versatile polyethers using nucleophilic species in the presence of a Lewis acid, i.e. triisobutylaluminium. This method enables the synthesis of α-,ω-plurihydroxytelechelic polyethers. The (co)polymerization of allyl glycidyl ether with various epoxides allowed the preparation of copolyethers with reactive side groups. A cyclo-carbonate functionalization was carried out in order to introduce hydroxyurethane functions by reaction with amines. This reaction allows the preparation of isocyanate-free polyurethane. Finally, resinic acids were modified chemically to prepare epoxy resins and isocyanate-free polyurethanes. A polyether based on epoxidized resinic derivatives was also synthesized by ring-opening anionic polymerization and monomer activation
31
Lin, Chia-Ho, et 林家禾. « Study of Waterborne Polyurethane Synthesized by the Biomass Polyester Polyols ». Thesis, 2014. http://ndltd.ncl.edu.tw/handle/eyzr65.
Texte intégralRésumé :
碩士國立高雄應用科技大學
化學工程與材料工程系碩士在職專班
102
In recent years, waterborne polyurethane gradually replaces solvent-based polyurethane under the environmental issues. However, in raw material of synthetics, petroleum-based polyester or polyether polyols are still used as soft segments of the polyurethane. Due to the gradual depletion of fossil energy; undoubtedly, it is a great contribution of energy and environmental protection and also make biomass material resources recovery and energy regeneration if we use biomass polyester polyol to replace petroleum-based polyol. In this research, the pre-polymer mixing process was applied to synthesize anionic type waterborne polyurethane. Dicyclohexylmethane-4,4'-diisocyanate (H12MDI) and isophorone diisocyanate (IPDI) were used as the hard segments. Dimethylolpropionic acid (DMPA) acted as the aqueous ionic center. Three kinds of long-chain polyols, biomass-based polyester polyols which are poly propylene succinates (PPS) with molecular weight of 1000 and 2000 and petroleum-based polyether polyol which is poly oxypropylene glycol (PPG) with molecular weight of 1900 were used as the soft segments. Three kinds of diols, 1,2-ethylene glycol (1,2-EG), 1,4-butylene glycol (1,4-BG) and 1,6-hexylene glycol (1,6-HG) were used as the chain extender of pre-polymers. Different formulations of waterborne polyurethane were synthesized and the effects of their viscosity, particle size, physical, mechanical, chemical and other properties on the different synthetic materials under the fixed NCO/OH ratio were also discussed. FTIR spectroscopy showed that waterborne polyurethanes produced by biomass-based polyester polyols and petroleum-based polyether polyol were both successfully synthesized. On the test of hydrolysis property, biomass-based polyester waterborne polyurethane is inferior to petroleum-based polyether waterborne polyurethane; however, biomass-based polyester polyol of high molecular weight can synthesize waterborne polyurethane with small particle size, low viscosity, high melting point and good heat resistance. On the tests of flexible resistance, phenol yellowing resistance, UV resistance and transparency, biomass-based polyester is similar to that of petroleum-based polyether waterborne polyurethane.
32
CAI, JIA-XIONG, et 蔡嘉雄. « Study in physical properties of polyurethane-modified unsaturated polyester resin ». Thesis, 1989. http://ndltd.ncl.edu.tw/handle/03780764077868223008.
Texte intégral
33
ZHENG, CHENG-XIU, et 鄭丞修. « Water Repellent and Breathable Polyester Fabric Prepared by Hydrophobic Waterborne Polyurethane ». Thesis, 2018. http://ndltd.ncl.edu.tw/handle/htbk32.
Texte intégral
34
Chang, Shyh-Yau, et 張世堯. « SYNTHESIS AND PROPERTIES OF PHOSPHORUS-CONTAINING POLYESTER DIOLS AND ITS POLYURETHANE RESINS ». Thesis, 1996. http://ndltd.ncl.edu.tw/handle/52565614930236208390.
Texte intégralRésumé :
碩士大同工學院
化學工程學系
84
Biphenyl phosphonate methylene succinic acid (Toyobo GH), aphosphorus-containing diacid monomer with the biphenyl phosphonategroup, has been synthesized by addition reaction of 9,10-dihydro-9-10-oxa-10-phosphaphenanthrene-10-oxide (HCA) with itaconic acid.The phosphorus-containing polyester diol (PEDO-IA) based on HCA /Itaconic acid was developed by the melt polycondensation of ToyoboGH, adipic acid(AA) and excess ethylene glycol(EG). The PEDO-IA, was then used to replace a portion of polyester or polyether diols in the formulation , to prepare both the linear phosphorus-containing polyurethane resins (P-PU) and the crosslinked phosphorus- containingpolyurethane resins (C-PU), by one shot process with 4,4'-diphenyl-methane diisocyanate (MDI), 1,4-butane diol (BDO) and trimethylolpropane (TMP). The different phosphorus content of polyurethane resins,ranging from 0.68--3.3 wt%, were prepared. The fire resistsnce of synthesized PU resins were evaluated by determining their limitingoxygen index (LOI). The thermal behavior measured by using thermo-gravimetric analysis (TGA). It is found that the crosslinked type(C-PU) has the best flame retardance efficiency, with 2.0 wt% oftotal phosphorus concentration in its compound. The LOI could increasefrom 20.5 to 27.8 and behave as self-extinguishing materials. Alsoit shown that the nearly perfect relationships between LOI vs. P%or N% in flame test indicated a synergistic effect between phosphorusand nitrogen. And that the tensile strength retention of the C-PUare over 85%. Results of TGA show that the P-PU exist lower decompositiontemperature and higher char yield residue (7.1 up to 26.2 wt%) thanthe conventional nonphosphorus-containing polyurethane. Both C-PU andP-PU are also found by dynamic mechanicial behavior to have higherrigidity and glass transition temperature than common PU.
35
HUANG, MING-XUN, et 黃明勳. « Study of glass fiber reinforced polyurethane/unsaturated polyester graft interpentrating polymer networks ». Thesis, 1990. http://ndltd.ncl.edu.tw/handle/35703677473993674327.
Texte intégral
36
Wu, Quan-kun, et 巫坤權. « Evaluation on the Manufacturing Technique and Properties of the Polyurethane coated Polyester Fabrics ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/87906254657369435786.
Texte intégralRésumé :
碩士逢甲大學
纖維與複合材料學系
104
The island of Taiwan is surrounded by seas. On holidays and weekends, more and more people are participating in water sports. Sports such as kite surfing, windsurfing, hang gliding, and paragliding have become increasingly popular in recent years. Therefore, research into the textiles used to manufacture kites, sails, parachutes, etc. is becoming increasingly important. This study uses 20D, 30D, and 40D polyester lattice fabrics and PU coating preparation and processing technology to prepare PU-coated fabrics. One to five PU coating layers are used in the preparation process in order to evaluate their effect on the performance of the polyester fabric samples. The weight, maximum tensile breaking strength, elongation at breaking point, tear strength, air permeability, bursting strength, weatherability, resistance to sea water, and resistance to changing PH are evaluated. Samples of the best-performing preparations are then compared with commercially available nylon 66 products and the differences are analyzed. The results show that, with a fixed coating speed of 13 m/min and a resin viscosity of 1500 cps, a 20D polyester lattice cloth with two coats, a 30D polyester lattice cloth with three coats, and a 40D polyester lattice cloth with four coats produce the best results for mechanical properties and air permeability. As for environmental factors, when comparing the coated polyester fabric to commercially available nylon 66 products, the results show that the coated polyester fabric has good weatherability and resistance to alkali, acids, and seawater. In comparison, the commercially available nylon 66 has good resistance to alkali and seawater, but low weatherability and poor resistance to acids. These research results demonstrate a polyester coating process that can be used to prepare cloth for the production of kite-surfing kites, windsurfing sails, and paraglider parachutes, etc.
37
LEE, MING, et 李銘. « Research for Process of Water-based Polyurethane Applied to Polyester Knitted Fabrics ─ Foam Coating Method ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/7p93m3.
Texte intégralRésumé :
碩士輔仁大學
織品服裝學系碩士班
104
In this study, served polyester-knitted down-proof fabrics with property of water-repellence as substrates for foam coating process with water-based polyurethane (acronym as WPU), which is able to make fabrics more anti-pilling, windproof, waterproof, water-repellent, soft, abrasion-resistant, washable, and so on, as dressed-coat provided. Test conditions were as follows: use reverse differential transfer foam applicator testing machine and set two types of variables of coating wheel speed and six variables of carved wheel speed ratio, then carried out seven performance examination test like water-repellence, air permeability, water-vapor permeability, water-pressure resistance, strength from stretch and tearing, etc. along with samples which are not coated, and analyzed physical properties of fabrics to assure that the coating process has reached commercial expectations. The down-proof fabrics used in the coating experiment has done the process for water-repellence. Hydrophobic materials need to bond with each other for hydrophobic bonds (bases) on the surface due to water-repellent agent on the surface of fabrics, just like paste has to be hydrophobic to laminate with sampled fabrics easily. Even though paste would be attached to fabrics and get much thicker into fabrics with adjustment of coating wheel speed and carved wheel speed ratio as paste in the state of moisture, paste is just attached fabrics terribly slightly, and if fabrics being rinsed, paste is going to be removed from fabrics immediately. However, hydrones from paste will be vanished, have thermal reaction, and produce adhesion with hydrophobic bond from water-repellent agent. Surfactants in the paste has both hydrophobic and hydrophilic bonds. Therefore, besides of previous description about hydrophobic bonds, moisture content will be absorbed by hydrophilic bases from the paste. Apertures discovered in the experiment are much smaller than a single drop of water but much larger than water-vapor. Therefore, apertures would keep fabrics from infiltration of moisture. This makes moisture move out from fabrics easily, and keeps clothing dry and comfortable to wear. As results demonstrated, after washing for 30 times, water-repellency of sampled fabrics’ coated face has great connection with its hydrophilic property to water molecules, led to lower water-repellency. Air permeability will get lower as carved wheel speed ratio and coating wheel speed have elevated. Tensile and tearing strength of warp from samples has been better than performance of weft. Sorting through the data analysis, the greater coating wheel speed and carved wheel speed ratio set, the more substantial emulsion polyester water-repellent knitted down-proof fabrics infiltrated. This makes fabrics’ water-repellency, air permeability, and water-vapor permeability obviously much lower, especially the thicker coated layer leads to lower water-repellency and water-vapor permeability based upon hydrophilic property of films. Films in the research are types of microporous membrane, paste scattering on the surface as well as into the sampled fabrics have extremely uniform performance with the observation activities from SEM. Apertures from samples are also well-distributed. WPU coating layers have great adaptability, fluidity, and produce the ease to attach to the surface of water-repellent polyester fabrics that wouldn’t be stuck between fabric faces. WPU coatings have sampled fabrics not only enhance their ductility but also create a soft feel as well as smooth surface just like woven fabrics. The PU paste is hydrophilic-type, which would decrease water-repellency, water-vapor, and air permeability of fabrics, and it won’t be influenced as much as a whole. However, the greater coating wheel speed and carved wheel speed ratio set, the thicker coated layer. Thicker coated layer would have PU paste penetrate into inner fibrous structure with much ease, which would make fibers rooted by the paste. As a result from experiment, water-pressure resistance, tensile strength, and tearing strength have been enhanced significantly. The original uncoated samples have the greatest water-repellency, water-vapor, and air permeability. Nevertheless, in discussion with results of water-pressure resistance, tensile strength, and tearing strength, the one with 0.6 m/min. coating wheel speed and 2-times carved wheel speed ratio (the greatest speed conditions set in the experiment) are the best.
38
Huang, Ting-Fen, et 黃婷芬. « Application of water-based polyurethane on the studies of the interface properties of the polyester fabric coating ». Thesis, 2013. http://ndltd.ncl.edu.tw/handle/94741109393185561482.
Texte intégralRésumé :
碩士國立雲林科技大學
化學工程與材料工程系碩士班
101
In this study, the series of anionic aqueous polyurethane were prepared from aliphatic isocyanate hydrogenated diphenylmethane diisocyanate (H_12 MDI), and mixtures of polyester polyol( polybutylene adipate (PBA) ), and polyether polyol (polyethylene glycol (PEG)). These PBA and PEG were used as a soft segment. Dihydroxymethyl propionic acid (DMPA) with carboxylic acid functional group, Triethylamine(TEA), and ethylenediamine (EDA) were incorporated into water based polyurethane(WBPU) as an internal emulsifier, neutralizer agent, and the chain extending agent, respectively. The water-based polyurethane was added with isocyanate crosslinking agent (FTC:NCO-J or BAYER:NCO-G), and then was coated on the polyester fabric for the investigation of peel strength,water resistance, and water vapor permeability. First, synthesize different ether/ ester ratios of soft segment of water based PU and adding different kinds of crosslinking agent. FITR was used for structural identification and observation of the molecular interaction forces between the crosslinking agent and the water-based PU. TGA and DSC were used to study the thermal properties of the film. The WBPU was coated on farbics, with different predring times and temperatures, and then FE-SEM was used to observe the adhesive types of interface between the PU coating solution and the farbics the interface. The peeling strength of the fabric, the waterproof, and water vapor permeability were investigated by universal tensile test, hydrostatic pressure test, and water vapor permeability test, respectively.
39
Huan, Chi Ching, et 冀靖寰. « The Effects of Polyurethane Emulsion Mixed with Waterborne PU Prepolymer on the Hydrophilic Finishing of Polyester Fabrics ». Thesis, 1994. http://ndltd.ncl.edu.tw/handle/94474441876709988731.
Texte intégralRésumé :
碩士國立臺灣科技大學
纖維工程技術系
82
In this study, the HMDI-based waterborne anionic PUs were synthesized to research the effect of variations of soft-type , content of anionic center and NCO/OH molar ratio on film properties. Afterwards, we mixed the above PU dispersions with thermoreactive waterborne PU prepoly- mer containing EO hydrophilic side chain to examine the influence of PU composition , amount of prepolymer and types of chain extender on the physical properties of under pad-dry-cure process treated polyester fabrics. In the investigation of physical properties of various PU dispersions , the results reveal that : when the com- parison of different soft PUs was done, the PU with ester type soft presented better mechanical properties and the PU based on PEG-mixed soft segment possessed the reduced breaking strength & initial modulus and improved extens- ibility due to irregular arrangement of mixed soft seg- ments, Secondly, with fixed soft composition, varying the content of anionic center and NCO/OH molar ratio, We dis- cover that mechanical strength increased and elongation decreased with anionic content and NCO/OH molar ratio,be- cause of the increases hard domain cohesion respectively. In application of polyester fabrics, the result direct that ester-type PU presented higher add-on and ether-type one improved softness. With increasing addition of pre- polymer, the add-on decreased and wicking height & water absorption increased greatly. In addition, the hydroph- ilicity & add-on were lowered with DMPA content. With NCO/OH molar ratio, the add- on increased and hydrophilic- ity & softness decreased. Finally, in variation of chain extender of finishing solution, DMPA presented highest add-on and fibroin improved moisture regain ratio and softness.
40
LIN, LI-XIANG, et 林立翔. « Curing of unsaturated polyester resins in reactive polymer processing-effects of adding polyurethane and polystyrene as low profile additives ». Thesis, 1992. http://ndltd.ncl.edu.tw/handle/13210013566501765257.
Texte intégral
41
CHU, Ching-CU, et 朱正九. « Miscibility and Curing Behavior of Polyester/Low Profile Additive Ternary System:Effects of Chemical structure and Molecular Weight of Polyurethane based Low Profile Additives ». Thesis, 1997. http://ndltd.ncl.edu.tw/handle/46784403992581681106.
Texte intégralRésumé :
碩士國立台灣工業技術學院
化學工程技術研究所
85
Synthesis of three series of thermoplastic polyurethane(PU)- based low profileadditives(LPA), and effects of chemical structure and molecular weight of theLPA on the miscibility of styrene(ST)/unsaturated polyester(UP) resin/LPA ternaryy systems at room temperature prior to reaction were investigated.The reaction kinetics during the cure at 110and the cured sample morphology for the low-shrinkunsaturated polyester resins containing PU were also studied by using a differential scanning calorimeter(DSC) and scanning electron microscopy(SEM) respectively.(keywords:themoplastic polyurethane(PU) ; low- profile additives(LPA) ; unsaturatedpolyester(UP) , miscibility ; cure)
42
Dong, Ji-ping, et 董志平. « Shrinking Characteristics, Internal Pigmentability and Mechanical Properties of Low-Shrink Unsaturated Polyester Resins : Effect of the Structure and Molecular Weight of Polyurethane-based Low Profile ». Thesis, 1997. http://ndltd.ncl.edu.tw/handle/63624109966625969497.
Texte intégralRésumé :
碩士國立台灣工業技術學院
化學工程技術研究所
85
The effect of five thermoplastic polyurethane(PU)-based low profile additives(LPA) with different chemical structure and molecular weight on the volume shrinkage chacteristics, internal pigmentability and mechanical properties for three low-chrink unsaturated polyester resin(UP) based on maleic anhydride(MA)- propylene glycol(PG), MA-PG-PA(phthalic anhydride), and MA-PG- IPA(isophthalic acid) types of UP respectively after the cure were investigated. The experimental results have been explained by phase chactistics of the ternary styrene/UP/LPA, reaction conversion, cured sample morphology, volume fraction of microvoid, and the composition change in the continuous crosslinked polyester phase as a result of phase separation during the cure.
43
黃兆緯. « Synthesis of poly(vinyl acetate) and polyurethane-based low-profile additives and acrylic type of core-shell rubber tougheners and their phase characteristics in styrene/unsaturated polyester/additive ternary systems ». Thesis, 2004. http://ndltd.ncl.edu.tw/handle/90567305559869291806.
Texte intégral
44
Anil, Kumar *. « Studies On Hyperbranched Polymers ». Thesis, 1995. http://etd.iisc.ernet.in/handle/2005/1846.
Texte intégral
45
Li, Ke, et 李科. « Studies on the synthesis and physical properties of polyester-type star polyurethanes ». Thesis, 1996. http://ndltd.ncl.edu.tw/handle/43342800780993720728.
Texte intégral
46
Pavlova, Ewa [Verfasser]. « Hyperbranched polyesters for polyurethane coatings : their preparation, structure and crosslinking with polyisocyanates / submitted by Ewa Pavlova ». 2006. http://d-nb.info/984382305/34.
Texte intégral