Bibliografias temáticas / Polymers

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Literatura científica selecionada sobre o tema "Polymers"

Autor: Grafiati

Publicado: 4 de junho de 2021

Última modificação: 28 de junho de 2025

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Artigos de revistas sobre o assunto "Polymers"

Chen, Guang, Lei Tao, and Ying Li. "Predicting Polymers’ Glass Transition Temperature by a Chemical Language Processing Model." Polymers 13, no. 11 (June 7, 2021): 1898. http://dx.doi.org/10.3390/polym13111898.

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We propose a chemical language processing model to predict polymers’ glass transition temperature (Tg) through a polymer language (SMILES, Simplified Molecular Input Line Entry System) embedding and recurrent neural network. This model only receives the SMILES strings of a polymer’s repeat units as inputs and considers the SMILES strings as sequential data at the character level. Using this method, there is no need to calculate any additional molecular descriptors or fingerprints of polymers, and thereby, being very computationally efficient. More importantly, it avoids the difficulties to generate molecular descriptors for repeat units containing polymerization point ‘*’. Results show that the trained model demonstrates reasonable prediction performance on unseen polymer’s Tg. Besides, this model is further applied for high-throughput screening on an unlabeled polymer database to identify high-temperature polymers that are desired for applications in extreme environments. Our work demonstrates that the SMILES strings of polymer repeat units can be used as an effective feature representation to develop a chemical language processing model for predictions of polymer Tg. The framework of this model is general and can be used to construct structure–property relationships for other polymer properties.

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Chen, Jian Fang, and Ai Hua Ling. "Design and Synthesis of a Miktoarm Star PMMAZO-(PCL)₂ Copolymer." Advanced Materials Research 332-334 (September 2011): 2089–92. http://dx.doi.org/10.4028/www.scientific.net/amr.332-334.2089.

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A series of novel miktoarm star polymers were synthesized by combination of at-om transfer radical polymerization(ATRP), chemical modification and ring-opening polymeri-zation(ROP). These miktoarm star polymers carring one poly[6-(4-methoxy-4’-oxy-azobenzene) hexylmethacrylate] azobenzene (PMMAZO) side-chain liquid crystalline(LC) arm and two polycaprolactone(PCL) arms. These precursors and miktoarm star polymers were characterized by proton nuclear resonance (1H-NMR), and gel permeation chramatograph(GPC). The information of PMMAZO(OH)2 and PMMAZO-(PCL)2 miktoarm star polymer confirmed the expected structure.

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Ansari, Aysha Praveen, Anamika Saini, Ila Joshi, Ajay Kumar, Varun Verma, Vikas Gupta, and Rekha Rikhari. "Conducting Polymers: Types and Applications." International Journal of All Research Education and Scientific Methods 13, no. 01 (2025): 01–19. https://doi.org/10.56025/ijaresm.2024.121224005.

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Conducting Polymers (CPs) represent a unique class of materials that combine the electrical conductivity of metals with the mechanical properties and processability of conventional polymers. This paper provides a comprehensive review of the various types of conducting polymers, including Polyaniline (PANI), Polypyrrole (PPy), Polythiophene (PT), and their derivatives. The synthesis techniques of these polymers, such as Chemical, Electrochemical, and Template-Based Methods, are discussed, highlighting their impact on the polymer's structure, conductivity, and functional properties. Each polymer type exhibits distinct characteristics, which can be tailored for specific applications through controlled synthesis. The diverse applications of CPs in fields such as organic electronics, sensors, energy storage devices, corrosion protection, and biomedical devices are also explored. Recent advancements in the development of nanostructured conducting polymers are emphasized for their potential to enhance performance in various devices. The review concludes by discussing the challenges in scalability, environmental impact, and the future prospects of conducting polymers in next-generation technologies.

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Brostow, Witold, Hanna Fałtynowicz, Osman Gencel, Andrei Grigoriev, Haley E. Hagg Lobland, and Danny Zhang. "Mechanical and Tribological Properties of Polymers and Polymer-Based Composites." Chemistry & Chemical Technology 14, no. 4 (December 15, 2020): 514–20. http://dx.doi.org/10.23939/chcht14.04.514.

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A definition of rigidity of polymers and polymer-based composites (PBCs) by an equation is formulated. We also discuss tribological properties of polymers and PBCs including frictions (static, sliding and rolling) and wear. We discuss connections between viscoelastic recovery in scratch resistance testing with brittleness B, as well as Charpy and Izod impact strengths relations with B. Flexibility Y is related to a dynamic friction. A thermophysical property, namely linear thermal expansivity, is also related to the brittleness B. A discussion of equipment needed to measure a variety of properties is included.

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Shahzadi, Maria, Taimoor Hassan, and Sana Saeed. "Application of Natural Polymers in Wound Dressings." Pakistan Journal of Medical and Health Sciences 16, no. 10 (October 30, 2022): 1–2. http://dx.doi.org/10.53350/pjmhs2216101.

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Natural polymers because of their biodegradability, biocompatibility and closeness to the extracellular matrix are frequently used in regenerative medicine for burns and wound dressing. By triggering and stimulating the wound healing process, natural polymers aid in the restoration of damaged tissues and, as a result, skin regeneration1. Natural polymers have proven to be effective in a variety of biomedical applications, such as controlled administration of drugs, gene delivery, and regenerative medicine, among others.Plants, animals, and microbial are the major sources responsible for production of natural polymers. Based on their chemistry natural polymers are divided into polysaccharide, protein, polyester, and polyamide-based polymers2. Because of their 3 D cross-link-based networks of polymer, immersed with water or other biological fluids, hydrogels are considered worthwhile in the Biomedical and pharmaceutical industries for wound care, burn dressing, medication administration, tissue engineering and transplantation of organs3. Natural polymers used in wound dressings: Here are several natural polymers which are effectively used in wound management.

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Martens, C. M., R. Tuinier, and M. Vis. "Depletion interaction mediated by semiflexible polymers." Journal of Chemical Physics 157, no. 15 (October 21, 2022): 154102. http://dx.doi.org/10.1063/5.0112015.

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We present a simple mean-field theory to describe the polymer-mediated depletion attraction between colloidal particles that accounts for the polymer’s chain stiffness. We find that for fixed polymer radius of gyration and volume fraction, the strength of this attraction increases with increasing chain stiffness in both dilute and semidilute concentration regimes. In contrast, the range of attraction monotonically decreases with chain stiffness in the dilute regime, while it attains a maximum in the semidilute regime. The obtained analytical expressions for the depletion interaction were compared with numerical self-consistent field lattice computations and shown to be in quantitative agreement. From the interaction potential between two spheres, we calculated the second osmotic virial coefficient B2, which appears to be a convex function of chain stiffness. A minimum of B2 as a function of chain stiffness was observed both in the numerical self-consistent field computations and the analytical theory. These findings help explain the general observation that semiflexible polymers are more effective depletants than flexible polymers and give insight into the phase behavior of mixtures containing spherical colloids and semiflexible polymers.

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Caldona, Eugene B., Ernesto I. Borrego, Ketki E. Shelar, Karl M. Mukeba, and Dennis W. Smith. "Ring-Forming Polymerization toward Perfluorocyclobutyl and Ortho-Diynylarene-Derived Materials: From Synthesis to Practical Applications." Materials 14, no. 6 (March 18, 2021): 1486. http://dx.doi.org/10.3390/ma14061486.

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Many desirable characteristics of polymers arise from the method of polymerization and structural features of their repeat units, which typically are responsible for the polymer’s performance at the cost of processability. While linear alternatives are popular, polymers composed of cyclic repeat units across their backbones have generally been shown to exhibit higher optical transparency, lower water absorption, and higher glass transition temperatures. These specifically include polymers built with either substituted alicyclic structures or aromatic rings, or both. In this review article, we highlight two useful ring-forming polymer groups, perfluorocyclobutyl (PFCB) aryl ether polymers and ortho-diynylarene- (ODA) based thermosets, both demonstrating outstanding thermal stability, chemical resistance, mechanical integrity, and improved processability. Different synthetic routes (with emphasis on ring-forming polymerization) and properties for these polymers are discussed, followed by their relevant applications in a wide range of aspects.

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Ewert, Ernest, Izabela Pospieszna-Markiewicz, Martyna Szymańska, Adrianna Kurkiewicz, Agnieszka Belter, Maciej Kubicki, Violetta Patroniak, Marta A. Fik-Jaskółka, and Giovanni N. Roviello. "New N4-Donor Ligands as Supramolecular Guests for DNA and RNA: Synthesis, Structural Characterization, In Silico, Spectrophotometric and Antimicrobial Studies." Molecules 28, no. 1 (January 3, 2023): 400. http://dx.doi.org/10.3390/molecules28010400.

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The present work reports the synthesis of new N4-donor compounds carrying p-xylyl spacers in their structure. Different Schiff base aliphatic N-donors were obtained synthetically and subsequently evaluated for their ability to interact with two models of nucleic acids: calf-thymus DNA (CT-DNA) and the RNA from yeast Saccharomyces cerevisiae (herein simply indicated as RNA). In more detail, by condensing p-xylylenediamine and a series of aldehydes, we obtained the following Schiff base ligands: 2-thiazolecarboxaldehyde (L1), pyridine-2-carboxaldehyde (L2), 5-methylisoxazole-3-carboxaldehyde (L3), 1-methyl-2-imidazolecarboxaldehyde (L4), and quinoline-2-carboxaldehyde (L5). The structural characterisation of the ligands L1-L5 (X-ray, 1H NMR, 13C NMR, elemental analysis) and of the coordination polymers {[CuL1]PF6}n (herein referred to as Polymer1) and {[AgL1]BF4}n, (herein referred to as Polymer2, X-ray, 1H NMR, ESI-MS) is herein described in detail. The single crystal X-ray structures of complexes Polymer1 and Polymer2 were also investigated, leading to the description of one-dimensional coordination polymers. The spectroscopic and in silico evaluation of the most promising compounds as DNA and RNA binders, as well as the study of the influence of the 1D supramolecular polymers Polymer1 and Polymer2 on the proliferation of Escherichia coli bacteria, were performed in view of their nucleic acid-modulating and antimicrobial applications. Spectroscopic measurements (UV–Vis) combined with molecular docking calculations suggest that the thiazolecarboxaldehyde derivative L1 is able to bind CT-DNA with a mechanism different from intercalation involving the thiazole ring in the molecular recognition and shows a binding affinity with DNA higher than RNA. Finally, Polymer2 was shown to slow down the proliferation of bacteria much more effectively than the free Ag(I) salt.

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Chang, L. L., D. L. Raudenbush, and S. K. Dentel. "Aerobic and anaerobic biodegradability of a flocculant polymer." Water Science and Technology 44, no. 2-3 (July 1, 2001): 461–68. http://dx.doi.org/10.2166/wst.2001.0802.

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Flocculant polymers are used to improve the efficiency of separation processes used in wastewater treatment. The subsequent fate and effects of these additives are uncertain, however, with some previous reports indicating them to be biodegradable while others indicate complete recalcitrance. The biodegradability of a common flocculant polymer was therefore evaluated, using both aerobic and anaerobic batch assays. Knowledge of the polymer's chemical composition also allowed degradation stoichiometries to be calculated for complete biodegradation and also for incomplete degradation to several hypothesized end products. Results showed conclusively that the polymer was subject to partial degradation by both aerobic and anaerobic cultures. Measured oxygen consumption under aerobic conditions, and gas production under anaerobic conditions, both indicate that the partial destruction of pendant cationic moieties occurs, but that the polymer's CH2 backbone remains essentially intact. These results allow seemingly contradictory previous reports to be explained. The findings are relevant to the environmental fate of these polymers as well as certain treatment process effects.

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Becskereki, Gergely, George Horvai, and Blanka Tóth. "The Selectivity of Molecularly Imprinted Polymers." Polymers 13, no. 11 (May 28, 2021): 1781. http://dx.doi.org/10.3390/polym13111781.

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The general claim about novel molecularly imprinted polymers is that they are selective for their template or for another target compound. This claim is usually proved by some kind of experiment, in which a performance parameter of the imprinted polymer is shown to be better towards its template than towards interferents. A closer look at such experiments shows, however, that different experiments may differ substantially in what they tell about the same imprinted polymer’s selectivity. Following a short general discussion of selectivity concepts, the selectivity of imprinted polymers is analyzed in batch adsorption, binding assays, chromatography, solid phase extraction, sensors, membranes, and catalysts. A number of examples show the problems arising with each type of application. Suggestions for practical method design are provided.

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Teses / dissertações sobre o assunto "Polymers"

Schlindwein, Walkiria Santos. "Conducting polymers and polymer electrolytes." Thesis, University of Leicester, 1990. http://hdl.handle.net/2381/33889.

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Polymers are mostly used as insulator materials. Since the late sixties, two new classes of polymeric materials possessing either ionic or electronic conductivities have been extensively studied. The work carried out in this thesis concerns of the study of polymer electrolytes based on poly(ethylene oxide) (PEO) complexed with divalent salts (ionic conductors) and polypyrroles (PPy) electrochemically and chemically prepared (electronic conductors). Different techniques were used to study their properties including Differential Scanning Calorimetry (DSC), Variable Temperature Polarising Microscopy (VTPM), Extended X-ray Absorption Fine Structure (EXAFS), a.c. Impedance, Cyclic Voltammetry, and Fourier Transform Infra-Red Spectroscopy (FTIR). Water-cast films of PEOn:ZnX2 (X = C1, Br, I) were prepared at a range of stoichiometries. The effects of either residual presence of water or thermal treatment related to the formation of high melting crystalline materials were investigated. The morphology of the zinc halides films differs from similar films cast from acetonitrile/methanol mixtures. The presence of high melting crystalline material in the water cast samples is influenced mostly by the concentration, type of anion and drying procedure applied to the samples. The high melting crystalline materials in the zinc samples are more affected by the drying regime. In some cases, solvent effects can be removed by using a high temperature (e.g. 180°C) drying regime. The presence of water normally depresses the melting temperature of the crystalline structures. Films of PEOn.:CaBr2 and PEOn:NiBr2 cast from water were also examined. The high melting crystalline materials in the calcium samples are more affected by the presence of water. The nickel samples are highly crystalline and the presence of high melting material does not seem to be influenced by either the presence of solvent or the drying procedure. EXAFS was used as a suitable technique to probe the local structure surrounding the cation. The results of the zinc halide samples gave some indication of the interionic and polymer-cation interactions. It was demonstrated that the halogen provides the most substantial contribution for the total EXAFS spectrum and the oxygen contribution is much less significant, except in the case of PEOn:ZnC12 samples. This could be due to the size of the nearest neighbour atoms and/or to the interaction polymer-cation. The presence of neutral "ion pairing" is suggested for the PEOn:ZnBr2 samples. The EXAFS results for the samples containing NiBr2 indicated a strong interaction between polymer-salt and the local structure was dependent on concentration, unlike the zinc samples. The polymerisation of pyrrole was investigated by using chemical and electrochemical oxidation routes. The structural characterisation of the compounds obtained was limited by their insolubility. The electrochemically prepared samples presented higher conductivity than the ones which were chemically prepared. The EXAFS results at the Fe K-edge of the PPyFeCl4 sample, which was prepared by direct chemical oxidation, suggested that the iron is coordinated to oxygens at a distance 1.97 A, chlorines at 3.08 A and perhaps nitrogens at 3.72 A. The iron local structure of the composite PVA/PPy doped with FeCl3 was different from the PPyFeCl4 sample. The iron in the composite sample was coordinated to oxygens at 1.98 A and chlorines at 2.18 A. Alternatively, the presence of a distorted FeCl4- is considered.

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Muangpil, Sairoong. "Functionalised polymers and nanoparticle/polymer blends." Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.654111.

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The incorporation of nanoparticles into polydimethylsiloxane polymers either in the form of physical blending or chemical crosslinking has long been studied as it can improve the properties of composite materials. Interactions between the host polymer and the filler particle, filler concentration and conformation of each component are the key factors that influence these properties. Understanding the effect of these factors is of fundamental importance in all practical applications of composite materials. This thesis describes the study of a range of PDMS composites by using a variety of experimental techniques. The main techniques used were spin-spin (T2) relaxation and diffusion NMR spectroscopy, rheology and small-angle neutron scattering (SANS). The molecular mobility of a series of PDMS melts has been studied for both unentangled and entangled molecular weight regimes separated by the critical entanglement molecular weight (Mc) of the polymer. The experimental results revealed the effect of molecular weight and polydispersity of the polymers on their segmental mobility. The dramatic decrease of chain mobility observed at molecular weight above Mc was attributed to the effect of chain entanglements. The effect of nano-sized trimethylsilylated polysilicate resin (R2) on the chain mobility of PDMS in the form of physically blended was also examined. Two different concentrations (17 and 30 vol%) of R2 were incorporated into a wide range molecular weight of PDMS melts. Below Mc, the R2 particle was found to reinforce the PDMS at all particle loadings, whereas a plasticisation effect was observed for high molecular weight PDMS above Mc. This was attributed to a reduction of the degree of the entanglements when polymer chains adsorbed on particles. Chemically bonded composites of PDMS and polyhedral oligomeric silsesquioxane (POSS) were successfully synthesised via hydrosilylation. The length of the PDMS central block was found to affect both the size and the molecular mobility of the triblock polymers. The weight fraction of POSS and substituted groups on POSS were also seen to affect the molecular mobility. Finally, a series ofrandom crosslink polymer films ofPDMS and phenylsilsesquioxane (TPh) was studied by AFM, TEM, SAXS and SANS techniques to investigate the factors influencing the optical clarity of the samples. The degree of swelling and the segmental mobility of the sample films swollen in good and poor solvents were also studied.

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Chester, Shawn Alexander. "Mechanics of amorphous polymers and polymer gels." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68898.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011. Cataloged from PDF version of thesis. Includes bibliographical references (p. 345-356). Many applications of amorphous polymers require a thermo-mechanically coupled large-deformation elasto-viscoplasticity theory which models the strain rate and temperature dependent response of amorphous polymeric materials in a temperature range which spans the glass transition temperature of the material. We have formulated such a theory, and also numerically implemented our theory in a finite element program. The material parameters in the theory have been calibrated for poly(methyl methacrylate), polycarbonate, and Zeonex - a cyclo-olefin polymer. The predictive capabilities of the constitutive theory and its numerical implementation have been validated by comparing the results from a suite of validation experiments against corresponding results from numerical simulations. Amorphous chemically-crosslinked polymers form a relatively new class of thermallyactuated shape-memory polymers. Several biomedical applications for thermally-actuated shape-memory polymers have been proposed/demonstrated in the recent literature. However, actual use of such polymers and devices made from these materials is still quite limited. For the variety of proposed applications to be realized with some confidence in their performance, it is important to develop a constitutive theory for the thermo-mechanical response of these materials and a numerical simulation-based design capability which, when supported with experimental data, will allow for the prediction of the response of devices made from these materials under service conditions. We have developed such a theory and a numerical simulation capability, and demonstrated its utility for modeling the thermo-mechanical response of the shape-memory polymer tBA-PEGDMA. An elastomeric gel is a cross-linked polymer network swollen with a solvent, and certain thermally-responsive gels can undergo large reversible volume changes as they are cycled about a critical temperature. We have developed a thermodynamically-consistent continuum-level theory to describe the coupled mechanical-deformation, fluid permeation, and heat transfer of such gels. We have numerically implemented our theory in a finite element program by writing thermo-chemo-mechanically coupled elements. We show that our theory is capable of simulating swelling, squeezing of fluid by applied mechanical forces, and thermally-responsive swelling/de-swelling of such materials. by Shawn Alexander Chester. Ph.D.

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Mohagheghian, Iman. "Impact response of polymers and polymer nanocomposites." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648854.

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Sun, Shuangyi. "Alkoxyphenacyl Polymers: A Novel Photodegradable Polymer Platform." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1424234383.

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Michal, Brian. "Multi-Functional Stimuli-Responsive Polymers." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1459440396.

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Smartt, William Mark. "Formation of microporous polymer via thermally-induced phase transformations in polymer solutions." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/32853.

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Amalou, Zhor. "Contribution à l'étude de la structure semi-cristalline des polymères à chaînes semi-rigides." Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210832.

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Les polymères semi-cristallins à chaînes semi-rigides, bien qu’abondamment utilisés dans la vie quotidienne, représentent des systèmes complexes qui ne sont pas encore parfaitement compris. Parmi les nombreux domaines de recherche sur cette famille de polymères, l’étude de la morphologie semi-cristalline et des processus de cristallisation et de fusion de ceux-ci restent des sujets très importants. L’investigation de la morphologie semi-cristalline est rendue difficile car elle présente une structure hiérarchique composée de plusieurs niveaux d’organisation, dont le plus petit est observable à une échelle très réduite de quelques nanomètres. De plus, les aspects liés à la cinétique des processus de cristallisation et de fusion n’ont pas toujours permis de bien les mettre en évidences, les rendant ainsi par très bien compris. Cependant, les nouvelles avancées technologiques dans le domaine de la physique expérimentales ont beaucoup profité à la science des polymères. Dans ce travail, une contribution originale est apportée à cette étude, et cela en combinant diverses techniques expérimentales permettant des mesures calorifiques et structurales en températures et temps réels. L’intérêt c’est porté sur les polymères linéaires aromatiques tels que le polyéthylènes teréphthalate, PET, et le polytriméthylène téréphthalate, PTT, caractérisés par une température de transition vitreuse supérieure à l’ambiante ( Tg > 50°) et une température de fusion élevée (Tm>220°C), offrant ainsi une assez large gamme de température de cristallisation (Tm-Tg). L’étude de la structure semi-cristalline du PET à l’échelle du nanomètre et de la relaxation des phases amorphes présentes dans sa structure est facilitée par l’utilisation d’un diluant amorphe tel que le polyétherimide (PEI), qui forme un mélange miscible avec le PET. L’utilisation de microscopie de force atomique AFM à haute température a permis d’observer la cristallisation isotherme de PET en temps réel et de décrire ainsi la cristallisation secondaire comme un processus d'épaississement des piles lamellaires. De plus, l’analyse de la structure semi-cristalline du PET et du PTT, dans l’espace direct, sont en faveur d’un modèle structural homogène, où l’épaisseur lamellaire moyenne est légèrement inférieure à l’épaisseur moyenne des régions amorphes interlamellaires. Ces résultats ont permis, d’une part, d’apporter une meilleure interprétation aux données obtenues par diffusion des rayons X aux petits angles (SAXS), et d’autre part, d’ interpréter le comportement de fusion multiple caractéristique des polymères semi-cristallin à chaînes semi-rigides par le seul processus de fusion-recristallisation. Dans l’étude investiguée sur les mélanges PET/PEI et sur le PTT pur, on montre que la cinétique d’un tel processus est particulièrement rapide comparée à la cristallisation. De plus, les observations par AFM et par microscopie optique de même que les mesures SAXS en temps réel ont montré la simultanéité et la compétition existant entre la fusion des cristaux et leur réorganisation durant la chauffe. Par ailleurs, la relaxation des régions amorphes interlamellaires, souvent considérées comme rigides, a pu être mise en évidence par les mesures AFM et SAXS réalisées à haute température sur des échantillons de PET/PEI semi-cristallins. Doctorat en sciences, Spécialisation physique info:eu-repo/semantics/nonPublished

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Cooke, Richard Hunter III. "THE ENHANCEMENT OF PEROXIDE-CURED FLUOROELASTOMER RUBBER TO METAL BONDING." Wright State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=wright1377022145.

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Yang, Lianyun. "Novel Ferroelectric Behavior in Poly(vinylidene fluoride-co-trifluoroethylene)-Based Random Copolymers." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1431686125.

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Livros sobre o assunto "Polymers"

Powell, Peter C. Engineering with polymers. 2nd ed. Cheltenham: Stanley Thornes, 1998.

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Godovsky, Yu K., K. Horie, A. Kaneda, N. Kinjo, L. F. Kosyanchuk, Yu S. Lipatov, T. E. Lipatova, et al. Speciality Polymers/Polymer Physics. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/bfb0017962.

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Akelah, A. Functionalized polymers and their applications. London: Chapman and Hall, 1990.

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Rubinson, Judith F., and Harry B. Mark, eds. Conducting Polymers and Polymer Electrolytes. Washington, DC: American Chemical Society, 2002. http://dx.doi.org/10.1021/bk-2003-0832.

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Chiellini, Emo, Junzo Sunamoto, Claudio Migliaresi, Raphael M. Ottenbrite, and Daniel Cohn, eds. Biomedical Polymers and Polymer Therapeutics. Boston, MA: Springer US, 2002. http://dx.doi.org/10.1007/b112950.

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I, Kroschwitz Jacqueline, ed. Polymers: Polymer characterization and analysis. New York: Wiley, 1990.

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Emo, Chiellini, and International Symposium on Frontiers in Biomedical Polymers including Polymer Therapeutics: From Laboratory to Clinical Practice (3rd : 1999 : Shiga, Japan), eds. Biomedical polymers and polymer therapeutics. New York: Kluwer Academic/Plenum Publishers, 2001.

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Donald, A. M. Liquid crystalline polymers. Cambridge [England]: Cambridge University Press, 1992.

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Efremovich, Zaikov Gennadiĭ, Bouchachenko A. L, and Ivanov V. B, eds. Aging of polymers, polymer blends and polymer composites. New York: Nova Science Publishers, 2002.

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Efremovich, Zaikov Gennadiĭ, Bouchachenko A. L, and Ivanov V. B, eds. Aging of polymers, polymer blends, and polymer composites. New York: Nova Science Publishers, 2002.

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Capítulos de livros sobre o assunto "Polymers"

Xanthos, Marino. "Polymers and Polymer Composites." In Functional Fillers for Plastics, 1–16. Weinheim, FRG: Wiley-VCH Verlag GmbH & Co. KGaA, 2005. http://dx.doi.org/10.1002/3527605096.ch1.

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Xanthos, Marino. "Polymers and Polymer Composites." In Functional Fillers for Plastics, 1–18. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2010. http://dx.doi.org/10.1002/9783527629848.ch1.

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Voisey, K. T. "Polymers and Polymer Composites." In The Engineer’s Guide to Materials, 97–124. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-62937-2_6.

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Iftekhar, Huma. "Polymers in Dentistry." In Materials Research Foundations, 397–412. Materials Research Forum LLC, 2025. https://doi.org/10.21741/9781644903353-17.

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Dentistry is notable for its diverse array of materials, which encompasses polymers, metal alloys, ceramics, composite materials and inorganic salts. Foundational understanding of polymer characteristics used in dentistry is beneficial because it offers insights pertinent for healthcare practice. Polymeric materials have found increased use in biological applications because of their many beneficial features and broad range of applicability. Significant advancement in the domains of engineering and nanotechnology has made these polymers possible to be customized for particular dental needs. In the present chapter, utilization of polymers in different branches of dentistry is discussed.

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Walton, David J., and J. Phillip Lorimer. "General principles and historical aspects." In Polymers. Oxford University Press, 2000. http://dx.doi.org/10.1093/hesc/9780198503897.003.0001.

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This chapter provides an overview of polymers, which are formed by linking large numbers of small molecules together. Polymers are now ubiquitous in daily life. Not only have polymers found a wide use in structural and textile materials, polymer substitutes have also found a wide application in medicine. Moreover, synthetic polymers have had a sizeable impact in the field of fibres, plastics, and rubbers (elastomers). While the majority of polymers are synthetic polymers, there are natural polymers such as proteins, natural rubber, and cellulose, each of which could be fitted into a similar category. It was as a result of early attempts to modify these natural materials that the important understanding of polymer behaviour arose. The chapter then presents the general principles of polymerization; the statistical nature of polymer chains; and the general principles of industrial polymer synthesis.

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Han, Chang Dae. "Rheology of Particulate-Filled Polymers, Nanocomposites, and Fiber-Reinforced Thermoplastic Composites." In Rheology and Processing of Polymeric Materials: Volume 1: Polymer Rheology. Oxford University Press, 2007. http://dx.doi.org/10.1093/oso/9780195187823.003.0018.

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Polymer composites consisting of a thermoplastic polymer forming the matrix phase and a large amount of inorganic particles (commonly referred to as fillers) or glass fibers, which are often referred to as particulate-filled polymers, are very common in the plastics and elastomer’s industries (Deanin and Schott 1974; Kraus 1965; Lubin 1969). Polymer composites are developed to achieve a set of properties not possessed by the thermoplastic polymer (i.e., polymeric matrix) alone. Polymeric matrices can be thermoplastics, which soften and behave as viscous liquids when heated to above their glass transition temperatures (in the case of amorphous thermoplastic polymers) or above their melting temperatures (in the case of semicrystalline thermoplastic polymers). Polymeric matrices can also be thermosets, which undergo a transformation from a viscous resinous liquid to a hard or rubbery solid in the presence of heat and/or curing agents. There are numerous industrial products made of particulate-filled polymeric materials; for example, thermoplastic polymers filled with mica or calcium carbonate, carbon-black-filled elastomers, thermoplastic polymers or thermosets reinforced with glass fibers or carbon fibers. The ultimate goal of adding fillers to a thermoplastic polymer and adding glass fiber or carbon fiber to a thermoset is to improve the mechanical properties of the polymer. However, fillers, glass fibers, or carbon fibers themselves usually supply little or no reinforcement since there is little interfacial interaction between a thermoplastic polymer and fillers, and between a thermoset and glass fiber or carbon fiber. This has led to the development of “coupling agents,” chemical additives capable of improving the interfacial bonds between a thermoplastic polymer and fillers, and between a thermoset and glass fibers or carbon fibers (Plueddemann 1982). The use of coupling agents for the surface modification of fillers to reinforce thermoplastics has generally been directed towards improving the mechanical strength and chemical resistance of composites by improving adhesion across the interface. When inorganic fillers or glass fibers are added to a thermoplastic polymer, the resulting material exhibits a complex rheological behavior, quite different from the rheology of neat homopolymers presented in Chapter 6.

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Han, Chang Dae. "Relationships Between Polymer Rheology and Polymer Processing." In Rheology and Processing of Polymeric Materials: Volume 1: Polymer Rheology. Oxford University Press, 2007. http://dx.doi.org/10.1093/oso/9780195187823.003.0005.

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Polymer products have long been used for a variety of applications in our daily lives, as well as for some more exotic applications, such as biomedical devices, superhigh- speed airplanes, and outer-space vehicles. Other applications are too numerous to mention them all here. There are many steps involved in the production of polymer products, from the synthesis of raw materials to the manufacturing of the finished products. Of the many steps involved, the fabrication (processing) step plays a pivotal role in determining the quality of the final products. Successful processing of polymeric materials requires a good understanding of their rheological behavior (Han 1976, 1981). Thus, intimate relationships exist between polymer rheology and polymer processing. In this chapter we describe briefly some of these close relationships between polymer rheology and polymer processing. Rheology is the science that deals with the deformation and flow of matter. Hence, polymer rheology is the science that deals with the deformation and flow of polymeric materials. Since there are a variety of polymeric materials, we can classify polymer rheology further into different categories, depending upon the nature of the polymeric materials; for instance, (1) the rheology of homogeneous polymers, (2) the rheology of miscible polymer blends, (3) the rheology of immiscible polymer blends, (4) the rheology of particulate-filled polymers, (5) the rheology of fiberglass-reinforced polymers, (6) the rheology of organoclay nanocomposites, (7) the rheology of polymeric foams, (8) the rheology of thermosets, (9) the rheology of block copolymers, and (10) the rheology of liquid-crystalline polymers. Each of these polymeric materials exhibits its own unique rheological characteristics. Thus, different theories are needed to interpret the experimental results of the rheological behavior of different polymeric materials. However, at present we do not have a comprehensive theory that can describe the rheological behavior of some polymeric materials and thus we must resort to empirical correlations to interpret the experimentally observed rheological behavior of those materials. It is then fair to state that a complete understanding of the rheological behavior of all polymeric materials remains quite a challenge indeed.

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Sachdeva, Amit, and Pramod K. Singh. "Reliability Study of Polymers." In AI Techniques for Reliability Prediction for Electronic Components, 45–54. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1464-1.ch002.

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The chapter deals with brief introduction to polymers, composites, and nanocomposites along with their reliability. When we talk about polymeric composites, the terms crystallinity and amorphicity play a very important role, and both of these properties are highly affected by variation in temperature condition. On increasing temperature, the crystalline domains of polymers tend to become amorphous, and as we reduce the temperature, crystalline domains tend to increase. So the reliability of a particular polymer is widely dependent on temperature conditions.

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Shirkhedkar, Atul A., Rajashri B. Sumbe, Kalyani A. Autade, Sachin N. Kothawade, and Amruta A. Banka. "Polymer Nanotechnology in Medicine." In Polymers in Modern Medicine (Part 1), 49–67. BENTHAM SCIENCE PUBLISHERS, 2024. https://doi.org/10.2174/9789815274585124010006.

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Polymeric nanomaterials possess a distinct set of properties for systems due to their large surface area to mass ratio, high reactivity, and nanoscale size. These attributes make them unique in many application fields. Their application in nanomedicine has completely changed therapeutic and diagnostic modalities because they are precisely engineered materials at the molecular level. Nanoparticles are widely used in site-specific controlled delivery and direct targeting to increase pharmacological efficacy and decrease side effects. Polymers are potentially perfect for meeting the needs of every specific drug-delivery system because of their versatility. Biodegradable and biocompatible polymers are commonly used in the fabrication of polymeric nanoparticles (PNPs). In this review, a summary of nanomedicine, targeted therapy with polymer nanoparticles, and diagnostic applications of polymer nanomaterials have been provided.

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Pawar, Ashish Y., Shubhangi N. Albhar, Sachin Namdeo Kothawade, and Deepak D. Sonawane. "Polymers in Diagnostics." In Polymers in Modern Medicine - Part 2, 111–34. BENTHAM SCIENCE PUBLISHERS, 2024. https://doi.org/10.2174/9789815322378124010008.

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Historically, laboratory verification has been the mainstay of medical diagnostics. This has resulted in arduous processes, expensive equipment, and a shortage of medically educated workers, not to mention delayed findings. However, the growing need for point-of-care medical testing devices coupled with the ongoing medical and digital technology integration has made it easier to create devices that have high selectivity, specificity, and quick reaction times. Every pandemic has brought attention to the development of these devices on a global scale, underscoring the pressing need to improve accurate, timely, and dependable medical diagnosis and treatment. The need for innovative methods of identifying biological entities with quick and precise diagnostic capacities is now growing steadily. Polymeric materials have been used as a key component in the development of several analytical procedures. Due to their easily adjustable characteristics, including their viscoelasticity, chemical and mechanical resistance, and adaptability, polymers have a wide range of uses. The fundamental benefit of employing polymers is their adaptability when mixed with other materials to produce products with a variety of physicochemical properties. Therefore, the physicochemical qualities of the polymer, which include its physical and chemical characteristics, may be changed to suit the needs of a particular application, which are Polymer-Based Sensors, Lab-on-a-Chip Technologies, and Polymer-Mediated Imaging Agents. Special focus is on polymers that form multifunctional, stable systems with nanostructured architecture. This chapter provides an overview of the sorts of polymeric materials and how they function in the operation of important diagnostic equipment.

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Trabalhos de conferências sobre o assunto "Polymers"

Fivizzani, Kenneth P., Leonard Dubin, Barbara E. Fair, and John E. Hoots. "Manganese Stabilization by Polymers for Cooling Water Systems." In CORROSION 1989, 1–15. NACE International, 1989. https://doi.org/10.5006/c1989-89433.

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Abstract Manganese from natural water sources causes deposition and associated corrosion problems in municipal and industrial water systems, particularly where chlorination is employed. Polymers are used to limit the precipitation of iron/manganese and manganese salts. Evidence for solubilization of manganese salts by polymeric and molecular agents has also been obtained. Factors such as dosage and composition have a significant impact on the performance of polymers. A polymer’s ability to perform effectively is also significantly affected by operating conditions such as temperature, pH, iron:manganese cation ratio and oxidizing conditions (e.g. air vs. chlorination). In zinc-based corrosion inhibiting programs, polymers have exhibited the ability to control precipitation of both zinc and manganese salts. Scanning electron microscopy and particle size distribution studies clearly indicate polymer performance is related to the ability to limit agglomeration of microparticulates. Application of these concepts suggests viable approaches for controlling manganese deposition in cooling water systems.

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Gu, Ji-Dong. "Microorganisms and Microbial Biofilms in the Degradation of Polymeric Materials." In CORROSION 2003, 1–18. NACE International, 2003. https://doi.org/10.5006/c2003-03570.

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Abstract Biodegradation and biodeterioration of polymeric materials affect a wide range of industries including manufacturing, aviation and space. Degradability of polymeric materials by microorganisms has been observed and the degree of degradability is determined mostly by the chemical structures of polymeric materials and the presence of degradative microbial population. Current understanding of polymer degradability has been advanced in recent years through the application of advanced detection techniques in both the biology of microorganisms and corrosion science, but the subject is still inadequately addressed. This is clearly shown by the limited amount of information available on biodeterioration of synthetic polymeric materials. In this review, polymers are treated according to their biodegradability, namely chemically modified natural polymers, synthetic polymers, recalcitrant polymers, and non-biodegradable polymers. One major advance in this area of research and development is the introduction of Electrochemical Impedance Spectroscopy (EIS) for sensitive detection of polymer degradation. Examples of the electronic insulation polyimides, fiber-reinforced polymeric composite and polymeric coatings by natural population of microorganisms have been established using this technique. Microorganisms and microbial biofilms are capable of degrading the material and fungi seem to be more effective than bacteria. During degradation, general EIS spectra indicative of microbial attack occur in several steps depending on the chemical composition of polymers. An initial decrease in impedance has been detected due to the transport of water and solutes into the polymeric matrices and a second decrease in impedance occurred as a result of polymer degradation. Microbial biofilms can form on surfaces of synthetic polymers and subsequent material degradation of materials due to the activities of microorganisms may be resulted. It is clear that candidate materials for use in different applications need to be carefully evaluated for susceptibility to microbial attack.

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Nicolas, George, Amannie Kweik, and Zahid Amjad. "Inhibitory Activity of Biopolymers, Synthetic Polymers, and Phosphonates against the Formation of Calcium Phosphate Scale in Cooling Water Systems." In CORROSION 2017, 1–13. NACE International, 2017. https://doi.org/10.5006/c2017-09013.

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Abstract The inhibition of calcium phosphate (Ca/P) precipitation by natural organic polyelectrolytes, bio- and hybrid polymers, homo- and co-polymers of acrylic acid and maleic acid containing different functional groups was examined in aqueous solution. Additionally, commonly used phosphonates were also evaluated as Ca/P inhibitors. It has been found that performance of additive (polymeric and non-polymeric) as Ca/P inhibitor depends upon additive concentration, ionic charge, and molecular weight. Based on the inhibition data, the ranking in terms of decreasing effectives is: biopolymer &gt; hybrid polymer &gt; natural organic polyelectrolytes. Among synthetic polymers the ranking order is: terpolymer &gt; co-polymer &gt; homopolymer. Results on phosphonates evaluation reveal that compared to synthetic polymers, phosphonates show poor performance as Ca/P inhibitors.

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Amjad, Zahid, and Peter G. Koutsoukos. "A Current Review of Polymeric Dispersants and Their Practical Significance in Industrial Water Treatment." In CORROSION 2019, 1–13. NACE International, 2019. https://doi.org/10.5006/c2019-12988.

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Abstract The fouling of equipment surfaces by suspended matter and precipitated scale forming salts is a critical concern to water technologists and plant operators. Certain feed waters, especially surface waters, require far more extensive pretreatment than sources such as deep wells. Polymeric dispersants are used in water treatment formulations to control fouling of equipment surfaces. This paper compares the performance of commercially available polymers as dispersants for a variety of suspended matter i.e., corrosion products, hydroxyapatite, clay, etc., under stressed industrial water system conditions. Results reveal that various factors including polymer architecture, water chemistry, nature of the substrates affect the performance of polymers. It has been observed that presence of water treatment formulation components i.e., homopolymers and phosphonates exhibit marked antagonistic effect on high performance dispersant performance. Additionally, zeta potential data on iron oxide suspensions show that the presence of copolymers compared to homopolymers results in marked increase in the negative charge of iron oxide particles. Based on the data collected, the performance of polymers may be ranked as follows: terpolymer &gt; -copolymer &gt; homopolymer &gt; hybrid polymer.

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Wilson, D. "Influence of Molecular Weight on Selection and Application of Polymeric Scale Inhibitors." In CORROSION 1994, 1–26. NACE International, 1994. https://doi.org/10.5006/c1994-94048.

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Abstract A homologous series of polycarboxylic acids of varying molecular weight have been evaluated in performance tests for their activity against sulphate and carbonate scales. Assessment of compatibility with brines and polymer efficiency both before and after thermal and hydrolytic stability testing was determined using jar and capillary tube blocking tests. Simulated 'squeeze' treatments on core samples have been performed to study the adsorption/desorption behaviour of the range of polymers. From test results on the polymers, it can be demonstrated that polymer molecular weight has a marked effect on the inhibition of different scale species. Thermal and hydrolytic data show the inherent stability of polymers. It can be concluded that specific scaling conditions can be treated by a particular series of polymers if selection of a suitable polymer is made using molecular weight as a criterion. The results demonstrate the applicability of polymers for scale control in 'squeeze' applications, treatment of produced waters, and seawater injection applications.

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Kweik, Amannie, and Zahid Amjad. "Study on the Effect of Polymer Architecture in Inhibiting Calcium Oxalate Precipitation." In CORROSION 2019, 1–13. NACE International, 2019. https://doi.org/10.5006/c2019-13014.

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Abstract In this study, the effect of polymer architecture (i.e., composition, functional group, monomer type, etc.) on calcium oxalate (CaOx) precipitation in aqueous solution was investigated using the spontaneous precipitation method. The polymers tested include: natural, bio-, and synthetic homo- and copolymers. The experimental results show that performance of polymers as CaOx inhibitors strongly depends on polymer architecture and type and charge of comonomers. In general, polymers containing carboxyl group perform better than co- and terpolymers containing hydrophobic and bulky comonomers. Analysis of XRD, FT-IR, and SEM data on the crystals grown in the absence of polymer reveal the formation of COM (calcium oxalate monohydrate) as the predominant phase. Results also indicate that presence of polymers in CaOx supersaturated solution favor the formation of COD (calcium oxalate dihydrate) phase.

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Smyk, E. B., J. E. Hoots, K. P. Fivizzani, and K. E. Fulks. "The Design and Application of Polymers in Cooling Water Programs." In CORROSION 1988, 1–20. NACE International, 1988. https://doi.org/10.5006/c1988-88014.

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Abstract Polymer technology for cooling water applications has advanced significantly in recent years. A variety of monomers and functional groups can be incorporated into a single polymer capable of handling a variety of problems. The development of cooling water polymers is traced through the design stage, screening and optimization, and final application testing. This process illustrates how structure can be modified to optimize performance. By choosing the best monomers and optimizing composition and molecular weight, new polymers with superior performance can be developed. These advancements in polymer design have resulted in programs with more flexible control ranges, tolerance to contaminants, and wider applicability.

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Bain, Douglas I., Grace Fan, Joseph Fan, and Robert J. Ross. "Scale and Corrosion Inhibition by Thermal Polyaspartates." In CORROSION 1999, 1–21. NACE International, 1999. https://doi.org/10.5006/c1999-99120.

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Abstract Organic polymers have found wide spread use as inhibitors for the prevention of mineral scales in heat transfer equipment. Recently a biodegradable organic polymer has been developed which provides both scale and corrosion control. The development of the polymeric inhibitor and laboratory evaluations of scale and corrosion inhibition is discussed together with its potential application in open recirculating cooling systems.

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Bykov, Alexey, Galina Demidenko, Linda Nikoshvili, and Elena Bakhvalova. "INFLUENCE OF THE NATURE OF AROMATIC POLYMER AS A PT PARTICLE STABILIZER ON ITS ACTIVITY AND SELECTIVITY IN THE LIQUID-PHASE HYDROGENATION OF AROMATIC AND POLYAROMATIC SUBSTRATES." In 24th SGEM International Multidisciplinary Scientific GeoConference 24, 123–30. STEF92 Technology, 2024. https://doi.org/10.5593/sgem2024/4.1/s17.16.

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A series of platinum catalytic systems stabilized in aromatic polymers were obtained in this work. Commercially available styrene-divinylbenzene (MN100) and polymers synthesized by one-stage crosslinking by the Friedel-Crafts reaction from benzene, naphthalene, and an equimolar benzene-naphthalene mixture were used as polymers. The obtained systems were tested in liquid-phase hydrogenation reactions of benzene, toluene, and benzene-toluene mixture, as well as anthracene in a dodecane medium. The reaction products were studied using GC-MS. Polymers and catalytic systems were studied using diffuse reflection IR spectroscopy, XPS, low-temperature nitrogen physisorption, thermogravimetry coupled with mass spectrometry, and TEM. The study of polymers by XPS and FTIR showed the presence of oxygen-containing functional groups with a similar nature in all polymers. The range of thermal stability of polymers was determined. The catalytic activity of 1%Pt/polymer systems in liquid-phase hydrogenation of solutions of pure benzene, toluene, and anthracene in dodecane, as well as an equimolar benzene-toluene mixture in dodecane, were compared. The dependence of the reaction rate, as well as the selectivity in the case of anthracene, on the nature of the aromatic blocks in the polymer matrix, was shown. The selectivity for cycloalkanes during hydrogenation of mononuclear arenes was 100%, regardless of substrate conversion. The selectivity of obtaining 9,10-dihydroanthracene at 90% anthracene conversion was found to be above 80% for all studied systems. In addition, the possibility of obtaining smaller diameter metal particles in the synthesized polymers in comparison with the industrial polymer MN100 was shown.

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Kim, Bumjoon J. "Design of electroactive polymers for intrinsically-stretchable polymer solar cells." In Organic, Hybrid, and Perovskite Photovoltaics XXV, edited by Gang Li and Natalie Stingelin, 41. SPIE, 2024. http://dx.doi.org/10.1117/12.3029279.

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Relatórios de organizações sobre o assunto "Polymers"

Lambeth, Robert H., Randy A. Mrozek, Joseph L. Lenhart, Yelena R. Sliozberg, and Jan W. Andzelm. Branched Polymers for Enhancing Polymer Gel Strength and Toughness. Fort Belvoir, VA: Defense Technical Information Center, February 2013. http://dx.doi.org/10.21236/ada577092.

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Bohnert, G. W. Conductive Polymers. Office of Scientific and Technical Information (OSTI), November 2002. http://dx.doi.org/10.2172/804936.

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Stavland, Arne, Siv Marie Åsen, Arild Lohne, Olav Aursjø, and Aksel Hiorth. Recommended polymer workflow: Lab (cm and m scale). University of Stavanger, November 2021. http://dx.doi.org/10.31265/usps.201.

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Polymer flooding is one of the most promising EOR methods (Smalley et al. 2018). It is well known and has been used successfully (Pye 1964; Standnes & Skjevrak 2014; Sheng et al. 2015). From a technical perspective we recommend that polymer flooding should be considered as a viable EOR method on the Norwegian Continental Shelf for the following reasons: 1. More oil can be produced with less water injected; this is particularly important for the NCS which are currently producing more water than oil 2. Polymers will increase the aerial sweep and improve the ultimate recovery, provided a proper injection strategy 3. Many polymer systems are available, and it should be possible to tailor their chemical composition to a wide range of reservoir conditions (temperature and salinity) 4. Polymer systems can be used to block water from short circuiting injection production wells 5. Polymer combined with low salinity injection water has many benefits: a lower polymer concentration can be used to reach target viscosity, less mechanical degradation, less adsorption, and a potential reduction in Sor due to a low salinity wettability effect. There are some hurdles when considering polymer flooding that needs to be considered: 1. Many polymer systems are not at the present considered as green chemicals; thus, reinjection of produced water is needed. However, results from polymer degradation studies in the IORCentre indicates that a. High molecular weight polymers are quickly degraded to low molecular weight. In case of accidental release to the ocean low molecular weight polymers are diluted and the lifetime of the spill might be quite short. According to Caulfield et al. (2002) HPAM is not toxic, and will not degrade to the more environmentally problematic acrylamide. b. In the DF report for environmental impact there are case studies using the DREAM model to predict the transport of chemical spills. This model is coupled with polymer (sun exposure) degradation data from the IORCentre to quantify the lifetime of polymer spills. This approach should be used for specific field cases to quantify the environmental risk factor. 2. Care must be taken to prepare the polymer solution offshore. Chokes and vales might be a challenge but can be mitigating according to the results from the large-scale testing done in the IORCentre (Stavland et al. 2021). None of the above-mentioned challenges are server enough to not consider polymer flooding. HPAM is neither toxic, nor bio-accumulable, or bio-persistent and the CO2 footprint from a polymer flood may be significantly less than a water flood (Dupuis et al. 2021). There are at least two contributing factors to this statement, which we will return in detail to in the next section i) during linear displacement polymer injection will produce more oil for the same amount of water injected, hence the lifetime of the field can be shortened ii) polymers increase the arial sweep reducing the need for wells.

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Salovey, Ronald, and John J. Aklonis. The Behavior of Polymers Filled with Monodisperse Polymeric Beads. Fort Belvoir, VA: Defense Technical Information Center, November 1991. http://dx.doi.org/10.21236/ada242732.

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Pang, Yi. Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties. Office of Scientific and Technical Information (OSTI), October 1991. http://dx.doi.org/10.2172/5097635.

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Ortega, Yina, and Felipe Salcedo. Transforming agriculture: advancements in compost-biopolymers composites for enhanced sustainability. Universidad de los Andes, December 2024. https://doi.org/10.51573/andes.pps.ss.bbb.11.

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In the Cesar Department in Colombia, sustainable agriculture faces critical challenges despite its thriving livestock sector. Extensive cattle ranching and poor soil management worsen soil conditions. Additionally, significant environmental concerns arise from the substantial discharge of wastewater in the dairy processing industry. This study aims to valorize biosolids derived from wastewater during dairy plant disinfection to enhance sustainable livestock production. It explores the use of biosolids as the primary matrix for creating composted compounds and biopolymers for agricultural purposes. These composite materials utilize composted biosolids from the dairy industry as the main matrix (60%), blended with biodegradable polymers such as polybutylene adipate succinate (PBSA) and polylactic acid (PLA) as functional agents. This innovative approach contrasts with the prevailing literature on composite polymer materials, where polymers typically form the matrix and agricultural residues serve as fillers. Biosolids from Freskaleche S.A. undergo controlled thermal treatment and composting before being combined with PBSA and PLA polymers using an internal mixer. The development of these new compounds includes the evaluation of thermal stability, Fourier-transform infrared spectroscopy (FTIR), and mechanical properties. It is noteworthy that Compost/PBSA composites exhibit promising compatibility and thermomechanical properties resembling pure PBSA, suggesting their potential as thermoplastic materials for producing plastic-based agricultural products. Regarding Compost/PLA blends, compost enhances chemical reactions in PLA polymeric chains, significantly altering their thermomechanical properties. This research provides valuable insights into the use of biosolids for manufacturing composite materials, offering a sustainable approach to address agricultural challenges in the Cesar region.

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Russell, Thomas P. Interfacial Behavior of Polymers: Using Interfaces to Manipulate Polymers. Office of Scientific and Technical Information (OSTI), February 2015. http://dx.doi.org/10.2172/1171152.

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Kempel, Leo, and Shanker Balasubramaniam. RF Polymers II. Fort Belvoir, VA: Defense Technical Information Center, March 2009. http://dx.doi.org/10.21236/ada495291.

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Phillips, Shawn H., Timothy S. Haddad, Rusty L. Blanski, Andre Y. Lee, and Richard A. Vaia. Molecularly Reinforced Polymers. Fort Belvoir, VA: Defense Technical Information Center, June 2001. http://dx.doi.org/10.21236/ada409917.

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Gordon, III, Runt Bernard, Painter James P., and Paul C. New Conducting Polymers. Fort Belvoir, VA: Defense Technical Information Center, June 1988. http://dx.doi.org/10.21236/ada197009.

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