Dissertations / Theses on the topic 'Condensation polymerization'

DNA condensation is the process in which an anionic polymer in combination with condensing agents undergoes a drastic reduction in volume and collapses into ordered structures. Double-stranded DNA has a uniform helical secondary structure, whereas single-stranded DNA is complex and adopts numerous different conformations. Novel mixed-stranded DNA molecules, with defined regions of both single-stranded and double-stranded secondary structures attached to one another in the same molecule, were created in this body of work. Mixed-stranded DNA was designed to be intermediate between its parent secondary structures in order to discover if mixed-stranded DNA will find a balance in terms of condensation properties as well. Mixed-stranded DNA was found to condense into minimally aggregated, globular particles in the presence of low mM concentrations of divalent transition metals in aqueous solvent at room temperature, a property not observed for either pure dsDNA or ssDNA. A model is presented to describe how mixed-stranded DNA -Mn2+, -Ni2+, and -Cd2+ condensates with the observed properties are produced. Multivalent-induced condensation of mixed-stranded DNA is also characterized and found to involve an unusual rod-like morphology in order to accommodate the secondary structures condensing independent of one another at different concentrations of multivalent cations. The attachment of a ss region to an otherwise ds molecule was found to greatly influence condensation properties of the entire molecule.

Les réacteurs à lit fluidisé (FBR) constituent la seule technologie viable sur le plan commercial pour la production de polyéthylène en phase gaz, car la polymérisation est hautement exothermique et le FBR est le seul type de réacteur en phase gaz offrant des possibilités suffisantes de transfert de chaleur. La nature hautement exothermique de cette polymérisation pose effectivement de nombreux problèmes pour le fonctionnement en phase gaz et peut limiter la production de certains procédés. Au cours des dernières années, les procédés en lit fluidisé ont été améliorés par de nouvelles technologies. En particulier, l'ajout d'hydrocarbures inertes (généralement liquides) permet d'augmenter la quantité de chaleur évacuée du réacteur. Ces composés augmentent la capacité calorifique de la phase gazeuse et, s’ils sont injectés sous forme liquide, s’évaporent également et absorbent ainsi encore plus efficacement la chaleur du milieu réactionnel. C’est ce qu’on appelle le fonctionnement en mode condensé. On y utilise des composés qui peuvent être liquéfiés dans le condenseur de recyclage et qui sont appelés agents de condensation induits (en anglais : Induced Condensing Agents - ICA). L’utilisation de l’ICA est extrêmement importante d'un point de vue industriel. L’injection d’ICA peut avoir de nombreux effets physiques différents au niveau des particules de polymère en croissance. Par exemple, l’ajout de ces composés peut entraîner des modifications de la solubilité et d’autres propriétés physiques, ce qui peut faciliter le transport de l’éthylène et de l’hydrogène vers les sites actifs des catalyseurs. Il est donc très important que les phénomènes physiques liés à l'équilibre de sorption entre la phase gaz et la phase polymère du ou des monomères et d'autres espèces, ainsi que leur diffusion dans la matrice polymère au niveau des sites actifs, soient pris en compte. En plus d'avoir un effet sur la cinétique, ces phénomènes peuvent également impacter la structure des molécules de polymère et par conséquent changer les caractéristiques du polymère. Identifier le comportement de ces phénomènes dans les conditions de la procédé et les variables de contrôle du rapport hydrogène / éthylène et du rapport comonomère / éthylène avec l'ICA sont les objectifs centraux de cette étude. Une série d’homo- et co-polymérisations d’éthylène en phase gazeuse a été réalisée en utilisant un catalyseur commercial Ziegler-Natta en présence de l’ICA (propane, n pentane et n-hexane). Nous avons étudié l’effet des températures, de la pression partielle de l’ICA, de l'hydrogène et des comonomères sur le comportement de la polymérisation. Il a été constaté que l’ajout de l’ICA augmentait significativement la vitesse de réaction ainsi que les poids moléculaires moyens à une température donnée. De manière inattendue, il a également été observé que l’augmentation de la température du réacteur en présence d’ICA entraînait en réalité une diminution de la vitesse de réaction globale. Ces résultats ont été attribués à l’effet de cosolubilité. Dans les réactions en présence de différentes concentrations en hydrogène, pour un rapport ICA/C2 beaucoup plus grand que le rapport H2/C2, l'effet de l’ICA sur la solubilité de l’éthylène peut compenser la diminution en taille des molécules provoquée par la présence d’hydrogène. L’impact de l’ICA sur les taux de réaction de copolymérisation est plus prononcé aux stades initiaux, perdant de son efficacité en raison de l'effet de comonomère. Enfin, une évaluation de la cinétique de cristallisation dans des conditions isothermes pour des mélanges de différentes concentrations ICA: HDPE a montré que le temps de cristallisation est significativement plus long pour les systèmes riches en ICA que pour les polymères secs
Fluidized bed reactors (FBR) are the only commercially viable technology for the production of polyethylene in the gas phase since the polymerization is highly exothermic and the FBR is the only type of gas phase reactor that offers adequate possibilities of heat transfer. The highly exothermic nature of this polymerization effectively poses many problems for gas phase operation and can limit the production of a certain process. However, in recent years the fluidized bed processes have been improved with new technologies. In particular, the addition of inert (usually liquefied) hydrocarbons allows one to increase the amount of heat removed from the reactor. These compounds increase the heat capacity of the gas phase and, if injected in liquid form, also evaporate and thus absorb even more heat from the reaction medium efficiently. This is known as a condensed mode operation. In it, one uses compounds that can be liquefied in the recycle condenser, and which are called Induced Condensing Agents (ICA). The use of ICA is extremely important from an industrial point of view. The injection of ICA can have many different physical effects at the level of the growing polymer particles. For instance, adding these compounds can cause changes in solubility and other physical properties, which can facilitate the transport of ethylene and hydrogen to the active sites of the catalysts. It is thus very important that the physical phenomena related to the sorption equilibrium of the monomer(s) and other species from the gas phase to the polymer phase, and their diffusion on the polymer matrix at the active sites should be accounted for. In addition to having an effect on the kinetics, these phenomena can also impact the structure of the polymer molecules and consequently qualify the characteristics of the polymer. Identifying the behavior of these phenomena under process conditions and control variables of the hydrogen/ethylene ratio and the comonomer/ethylene ratio with ICA are central objectives of this study. A series of ethylene homo- and co-polymerizations in the gas phase were carried out using a commercial Ziegler-Natta catalyst in the presence of ICA (propane, n-pentane, and n-hexane). We investigated the effect of temperatures, the partial pressure of ICA, hydrogen, and comonomers on the behavior of the polymerization. It was found that adding ICA significantly increased the reaction rate and average molecular weights at a given temperature. It was also unexpectedly observed that increasing the reactor temperature in the presence of an ICA actually led to a decrease in the overall reaction rate. These results were attributed to the socalled cosolubility effect. In reactions in the presence of different hydrogen concentrations, for an ICA/C2 ratio much larger than the H2/C2 ratio, the effect of ICA on ethylene solubility can counteract the decrease in average molecular weight caused by the presence of hydrogen. The impact of ICA on the rates of copolymerization reactions is more pronounced in the initial stages, losing strength due to the effect of the comonomer. Finally, an evaluation of the kinetics of crystallization under isothermal conditions for mixtures of different ICA:HDPE concentrations showed that the crystallization time is significantly higher for systems rich in ICA than for dry polymer

Les études présentées dans le cadre de cette thèse visent à copolymériser l'ԑ-caprolactame (CL) avec différents dérivés de l'α-amino-ԑ-caprolactame (qui possèdent une amine primaire fonctionnalisable) par polymérisation anionique par ouverture de cycle. En utilisant cette stratégie, nous décrivons; (i) la préparation de polyamides 6 fluorés thermiquement plus stables, et ayant une surface hydrophobe; (ii) la synthèse de polyamides 6 portant des groupes pendants cinnamoyl thermo et photosensibles. Une réticulation réversible est observée ainsi que l'amélioration des propriétés thermo-mécaniques; (iii) la copolymérisation anionique par ouverture de cycle de CL avec un bis-monomère issu de l'α-amino-ԑ-caprolactame comme contrôle de la réticulation du polyamide 6. Enfin, dans le cadre de notre intérêt continu pour la chimie du polyamide 6, nous avons mis en évidence la possible combinaison de la polymérisation anionique par ouverture de cycle de CL avec la polycondensation en chaîne de l'éthyl-4-butylaminobenzoate pour obtenir en une étape un polyamide aliphatique/aromatique
The studies presented in this thesis aim to copolymerize ԑ-caprolactam (CL) with different derivatives of α-amino-ԑ-caprolactam (which has a functionalizable primary amine) via anionic ring-opening polymerization. By using this strategy, we describe: (i) the synthesis of thermally more stable fluorinated polyamide 6 having a hydrophobic surface; (ii) the synthesis of polyamides 6 bearing pendant cinnamoyl groups, which are thermo-and photoresponsivechromophore groups, and demonstrating their reversible crosslinking as well as improved thermo-mechanical properties; (iii) the copolymerization ofCL with a crosslinker (N-functionalized α-amino-ԑ-caprolactambis-monomers) into crosslinked polyamides 6.As part of our continuing interest in polyamide 6 chemistry, we developed the combination of anionic ring-opening polymerization of CL and chain-growth condensation polymerization of ethyl 4-butylaminobenzoate in order to obtain aliphatic/aromatic polyamides in one-step

The objective of this study is to synthesize nematic-thermotropic liquid crystalline polymers (LCP) and determine their possible application areas. In this context, thirty different LCP&rsquo
s were synthesized and categorized with respect to their fiber formation capacity, melting temperature and mechanical properties. The basic chemical structure of synthesized LCP&rsquo
s were composed of p-acetoxybenzoic acid (p-ABA), m-acetoxybenzoic acid (m-ABA), hydroquinone diacetate (HQDA), terephthalic acid (TPA) and isophthalic acid (IPA) and alkyl-diacids monomers. In addition to mentioned monomers, polymers and oligomers were included in the backbone such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) polymers, and polybutylene naphthalate (PBN), polyhexylene naphthalate (PHN) and poly butylene terephthalate (PBT) oligomers that contain different kinds of alkyl-diols. We adjusted the LCP content to have low melting point (180oC-280oC) that is processable with thermoplastics. This was achieved by balancing the amount of linear (para) and angular (meta) groups on the aromatic backbones together with the use of linear hydrocarbon linkages in the random copolymerization (esterification) reaction. LCP species were characterized by the following techniques
Polarized Light Microscopy, Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared Analysis (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), X-ray Scattering (WAXS, Fiber diffraction), surface free energy, end group analysis (CEG), intrinsic viscosity (IV) and tensile test. According to these analysis LCPs were classified into five main categories
(I) fully aromatics, (II) aromatics+ PET/PEN, (III) aromatics + oligomers (IV) aromatics + short aliphatic diacids, (V) aromatics + long aliphatic diacids. The foremost results of the analysis can be given as below. DSC analysis shows that some LCPs are materials that have stable LC mesogens under polarized light microscopy. In TGA analysis LCPs that have film formation capacity passed the thermal stability test up to 390oC. NMR results proved that predicted structures of LCPs from feed charged to the reactor are correct. In FTIR due to the inclusion of new moieties, several peaks were labeled in the finger-print range that belongs to reactants. In X-ray analysis, LCP24 (containing PET) was found to be more crystalline than LCP25 (containing PEN) which is due to the symmetrical configuration. Block segments were more pronounced in wholly aromatic LCP2 than LCP24 that has flexible spacers. Another important finding is that, as the amount of the charge to the reactor increases CEG value increases and molecular weight of the product decreases. Selected group V species were employed as reinforcing agent and mixed with the thermoplastics
acrylonitrile butadiene styrene (ABS), nylon6 (PA6), polyethylene terephthalate (PET), polypropylene (PP) and appropriate compatibilizers in micro compounder and twin screw extruder. The blends of them were tested in dog-bone and/or fiber form. In general LCPs do not improve the mechanical properties except in composite application with polypropylene. A significant increase in tensile properties is observed by LCP24 and LCP25 usage. Capillary rheometer studies show that the viscosity of ABS decreases with the inclusion PA6 and LCP2 together. In addition to the composite applications, some LCPs are promising with new usage areas. Such as nano fibers with 200nm diameter were obtained from LCP27 by electrospinning method. The high dielectric constant of LCP29 has shown that it may have application areas in capacitors.

Dans le cadre d’un projet d’Intensification de Procédés de Rhodia, nous avons développé des dispositifs millifluidiques fonctionnant dans des conditions opératoires inexplorées auparavant au labortoire, jusqu’à 300 °C et 50 bar, pour l’acquisition de données physicochimiques. Ainsi, une étude rhéologique sur des solutions de sel de nylon a été réalisée, ce qui a permis de fournir une nouvelle corrélation utile pour le dimensionnement du procédé industriel de polymérisation du polyamide-6,6. Par ailleurs, une étude cinétique de la polymérisation de l’éthylène glycol avec l’acide adipique a permis de déterminer les coefficients cinétiques de la réaction ainsi que l’énergie d’activation correspondante. Finalement un procédé miniaturisé avec élimination de l’eau produite par la réaction de polycondensation permettant de déplacer l’équilibre atteint par la réaction a été mis en œuvre ainsi que son modèle
This work originated from a Rhodia’s Process Intensification project, where new physicochemical data are needed. We have developed at the laboratory new millifluidic devices which operate in conditions previously unexplored: up to 300 °C and 50 bar. A rheological study on nylon salt solutions was carried out and a new correlation based on the experimental results was provided. It is now used in the design of the industrial process of polyamide-6,6 synthesis. Moreover, a kinetic study on the polymerization of ethylene glycol with adipic acid allowed us to determine the kinetic coefficients of the reaction and the corresponding activation energy. Finally, a millifluidic process where the water produced by the polymerization reaction is eliminated by stripping and membrane separation was also developed, allowing for the chemical equilibrium to be shifted. A model describing this process has also been proposed

Synthese d'hygrogels, constitues de chaines elastiques de polydioxolanne. Les reticulats sont synthetises en milieu organique par couplages multiples des extremites hydroxylees, du polydioxolanne precurseur avec un compose isocyanate plurifonctionnel. Apres reaction, un echange progressif du solvant organique par l'eau permet d'obtenir les hydrogels

At the metaphase-to-anaphase transition, spindle microtubules pull replicated chromosomes to the daughter cells, but full separation of long chromosome arms is achieved in late anaphase. We have created an allelic series of long chromosomes to elucidate the mechanisms involved in long chromosome resolution during mitosis. With this method we have shown that long chromosome cells are sensitized to the loss of genes involved in chromosome structure and segregation. We have discovered that Topoisomerase II is needed during anaphase to resolve distal regions of long chromosomes and that the activity of the microtubule polymerase Stu2 is crucial in the resolution of catenations. Moreover, we have identified the nuclear organization as a new source that contributes to the topological stress accumulated in chromosomes. Thus, topological constraints imposed by chromosome length and nuclear architecture determine the amount of sister chromatid intertwinings that must be resolved by Topoisomerase II and dynamic microtubules during anaphase.
A la transició entre metafase i anafase els microtúbuls del fus mitòtic transporten els cromosomes a les cèl·lules filles, tot i això la separació completa dels braços dels cromosomes no succeeix fins al final dʼanafase. Amb lʼobjectiu dʼentendre com es resolen els cromosomes llargs durant anafase, hem creat una sèrie al·lèlica de cromosomes artificalment llargs. Amb aquesta metodologia hem demostrat que les cèl·lules que contenen cromosomes llargs estan sensibilitzades a la pèrdua de gens involucrats en lʼestructura i la segregació de cromosomes. Hem descobert que la Topoisomerasa II es necesària durant anafase per resoldre les regions distals de cromosomes llargs i que lʼactivitat de la polimerasa de microtúbuls, Stu2, és essencial en la resolució de concatenacions entre cromàtides germanes. A més, hem pogut identificar lʼorganització nuclear com una nova font que contribueix a lʼestrés topològic acumulat als cromosomes. En conclusió, les restriccions topològiques que imposen tant la longitud dels cromosomes com lʼarquitectura nuclear determinen la quantitat de concatenacions entre cromàtides germanes que han de ser resoltes per la Topoisomerasa II i els microtúbuls dinàmics durant anafase.

The possibility to control molar mass and termination of the growing chain is fundamental to create well-defined, reproducible materials. For this reason, in order to apply polydithienopyrrole (PDTP) as organic conjugated polymer, the possibility of controlled polymerization needs to be verified. Another aspect that is still not completely explored is bound to the optical activity of the PDTP, which bearing appropriate substituents may adopt a helical conformation. The configuration of the helix, built up from achiral co-monomers, can be established in an enantiopure way by using only a small percentage of the chiral monomer co-polymerized with achiral co-monomer. The effect, called “sergeants and soldiers effect”, is expressed by the nonlinear increase of the chiral response vs the ratio of the chiral co-monomer used for the polymerization. To date, this effect is still not completely explored for PDTP. In this framework the project will investigate, firstly, the possibility to obtain a controlled polymerization of PDTP. Then, monomers with different side chains and organometallic functions will be screened for a CTCP-type polymerization. Also a Lewis-acid based cationic polymerization will be performed. Moreover the chemical derivatization of dithienopyrrole DTP is explored: the research is going to concern also block copolymers, built up by DTP and monomers of different nature. The research will be extended also to the investigation of optically active derivates of PDTP, using a chiral monomer for the synthesis. The possibility to develop a supramolecular distribution of the polymeric chains, together with the “sergeants and soldiers effect” will be checked investigating a series of polymers with increasing amounts of chiral monomer.

Les critères actuels d'arrêt de synthèse des résines polyesters sont insuffisants pour garantir la fabrication du produit désiré qui passe par une meilleure connaissance du procédé ; le travail de modélisation présenté dans ce mémoire a donc été réalisé dans le cadre d'un projet qui a pour ambition de fournir un outil de simulation dynamique permettant d'aider les ingénieurs à mieux comprendre le fonctionnement d'un procédé et les opérateurs à mieux conduire la synthèse effectuée. Les bilans instantanés de matière et d'énergie ont été établis pour chaque partie de l'installation considérée (réacteur, colonne, condenseur). Une méthodologie a été mise au point pour décrire le système réactionnel correspondant à la production de polyesters insaturés. Le système d'équations algébro-différentielles a été intégré à l'aide de l'algorithme DASSL, modifié pour gérer au mieux les événements rencontrés ainsi que les discontinuités du modèle. Une analyse de ce modèle a été opérée pour utiliser les possibilités de la programmation orientée objet lors de l'écriture du logiciel de simulation. Il s'avère que l'utilisation de ce langage dans l'environnement Windows a permis de développer un outil convivial pour l'utilisateur et pour le programmeur, Simulbatch. Le modèle a été validé pour des chauffages-refroidissements et des distillations d'inertes. A l'aide d'expériences spécifiques, les paramètres cinétiques des réactions principales de la synthèse du polymaléate de propylène glycol ont pu être estimés par le logiciel. L'étude de la cinétique de polyésterification avec prise en compte du départ de l'eau, ceci par l'intermédiaire d'une réaction fictive, a permis d'établir une équation de vitesse applicable quelles que soient les conditions de la synthèse. La théorie de Flory-Huggins a été utilisée pour représenter l'équilibre liquide-vapeur du mélange polyester-monomère-condensat. Avec ces données, le logiciel reproduit correctement l'évolution dynamique des températures et des concentrations

Polycondensation de molecules diinsaturees, mono- ou polycycliques avec des molecules disilylees (hydrosilylation des doubles liaisons par des fonctions si-h. Les polymeres ont des masses moleculaires comprises entre 3000 et 25000. Stabilite thermique jusqu'a 450**(o)c

Polycondensation de l'acide trans stilbenedicarboxylique-4,4' (soa) avec des alpha ,omega -diamino alcanes et des alpha ,omega -diamino oligoethers. Etude de l'incorporation du soa dans des copolyarylates comme le poly(isophtalate de methyl phenylene) en vue d'obtenir des polymeres cristaux liquides, et des polyesters obtenus a partir d'autres monomeres (acide terephtalique). Amelioration des proprietes mecaniques des polycondensats par incorporation d'unites stilbeniques et d'acide p-acetoxybenzoique

Thesis (Ph. D.)--University of Wisconsin--Madison, 1998.
Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (357-378).

碩士
國立臺灣師範大學
化學學系
82
Crown ethers, e.p.18-crown-6 (18C6), monobenzo-15-crown-5 (B15c5) and 12-crown-4 (12C4), were applied as phase transfer catalysts for anionic polymerization of methyl methacrylate and Aldol condensation of phenyl acetaldehyde Lariat carboxylate crown ether, e,p. 2-(sym-dibenzo-16-crown-5oxy) dodecanoic acid (C10 H21 DB16C5 COOH), was synthesized and applied as ion transport carrier (Ionophore) for various metals ions and amino acids. 　　The solubility and activity of sodium amide (NaNH2) as an initaitor can be enhanced in presence of crown ethers which were able to complex with sodium ion of initator adn thus promote the anionic polymeriation of methy1 methacrylate in organic phase the catalytic ability of crown cthers, the 15 crown5 seems to be the best one, are in the order:15C5>B15C5>18C6>12C4.Effects of initiators, concentration of crown ethers, temperature and solvents on the polymerization of methyl methacrylate were also investigated and discussed the molecular weight of polymethyl methacrylate was determined with GPC (Gel permeation chromatography) method. 　　The lariat carboxylate crown ether alkyl substituted 2-(sym-dibenzxo-16-crown-5-oxy) was synthesized and applied as an ion transport carrier through liquid membrane for various metal ions such as alkali, alkali earth and transition metal ions and amino acid anions. the lariat carboxylate crown ether C10H21DB16C5COOH shhowed better ion transport ability than DB16C5COOH and B15C5 Effects of anion and pH in source layer were investigated An ion transport mechanism is proposed which included [OH-] and[H+] is strongly depended on the pH values of both source and target layer. 　　Various crown ethers were also applied catalysts for Aldol condensation of phenyl acetaldehyde with hydroxide (MOH). The elevation of temperature the increase in polarity of the reation solvent resulted in the increase of the reation yield. Effects of hydroxide and crown ethers were also investigated The reactive ability of hydroxide with 15 crown 5 as a catalyst are in the order: NaOH>KOH>LiOH.The Catalytic ability of various crown ethers for the condensation with NaOH as a reactant are in the order:15C5>B15C5>18C6>12C4.

碩士
臺灣大學
化學工程學研究所
95
Microcapsules can prevent the wrapped core materials from evaporating, extend the releasing time and stabilize the core materials during storage. Since fragrant oil has high evaporation property, it is very suitable to be treated by microencapsulation for further applications. In this study, we used melamine and formaldehyde as the shell materials with fragrant oil as the core materials to prepare microcapsules by condensation polymerization method. The purpose of this research is to synthesize the microcapsules containing fragrant oil with narrow size distribution and high capacity. Six factors considered in our experiments include temperature, stirring rate, the mass ratio of fragrant oil, the kinds of emulsifiers, and the mass ratio of emulsifier. It was found that, the higher the stirring rate or the lower the mass ratio of fragrant oil, the smaller the average diameter of microcapsules. In addition, by employing the software of Design-Expert 5 to analyze the experimental data, it was concluded that the degree of the effect of the factors on the particle size of microcapsules follows the order of the mass ratio of emulsifier > the mass ratio of fragrant oil >> stirring rate > temperature, and that on the encapsulating efficiency of microcapsules follows the order of the mass ratio of emulsifier > the mass ratio of fragrant oil >>temperature≒stirring rate.

碩士
國立虎尾科技大學
材料科學與綠色能源工程研究所在職專班
99
Fluorescent pigments vastly used in plastics coloration, one cause of color migration problems is high temperature will cause sample to migrate faster. Also causes reduction in fluorescence intensity and makes the sensitive to different colors when the plastic product has been made. 　　The aim of the study is to prepare alkyd resin by melt condensation polymerization method. Taguchi analysis was carried out and the signal-to-noise ratio and the analysis of variance were employed to determine the optimal combination of design parameters, including zinc stearate content, adhesion promoter content, melamine content, and reaction time, such that analyzed of the relative color intensity. The optimal parameter settings were used to evaluate the effects of injection molding parameters such as melt temperature and residence time, and UV accelerated aging tests, in relative color intensity and CIE LAB color difference were analyzed. 　　The experimental results show that melamine content was found to be the major parameter among the other control factors on relative color intensity, followed by including zinc stearate content. The adhesion promoter content and reaction time also had a significant effect on it, but they exerted much lower effect compared with the other factors. Moreover, the optimal combination of the testing parameters could be determined and predicted. A good agreement between the predicted and actual relative color intensity was observed within the 95% confidence interval. Besides, increased melt temperature in the injection molding process show higher fluorescence intensity in the wavelength range of 440-465 nm. After the UV exposure test, the fluorescence intensity obviously changed in the 580-700 nm spectral ranges.

碩士
國立中正大學
化學工程研究所
87
Abstract Conventional alkyl 2-cyanoacrylate adhesives have such defects as emitting an irritating and having a tendency to cause whitening, thus resulting in a scattering of white powder on the adherend surface upon application. Furthermore, when the alkyl 2-cyanoacrylate adhesive is cured, the cured polymer is hard and brittle and lacks flexibility,therefore it’s impact and flexure resistance is insufficient. Howerever an ether-linkage-containing alkyl 2-cyanoacrylate, ie, 2-ethoxyethyl cyanoacrylate, can overcome this problem. 2-Ethoxyethyl cyanoacrylate is made from 2-ethoxyethyl cyanoacetate and paraformadehyde. Based on Fischer esterification and the reaction condition described in the U.S.patent 5,347,032 try, this product has been synthesized in our lab successfully. Afterwords we have used GC, GC/MS, FTIR, NMR to characterize the product. The reaction between 2-ethoxyethyl cyanoacetate and formaldehyde is the first step in the 2-ethoxyethyl cyanoacrylate adhesive synthesis. The interaction between NC－CH2－COOR and HCHO can be desribed as a Knovenagel reaction. In our experiments it has been found that the temperature and the azeotropic solvents will determinate the Mn of the oligmer. Besides, the Mn will become smaller durning the reaction time. The observations in our experiments can be best explained by the mechanism proposed by K.G.Chorbadjiev and P.Ch.Novakvo.

Chain growth condensation polymerization is a powerful tool towards the synthesis of well-defined polyamides. This thesis focuses on one hand, on the synthesis of well-defined aromatic polyamides with different aminoalkyl pendant groups with low polydispersity and controlled molecular weights, and on the other hand, on studying their thermal properties. In the first project, well-defined poly (N-octyl-p-aminobenzoate) and poly (N-butyl-p-aminobenzoate) were synthesized, and for the first time, their thermal properties were studied. In the second project, ethyl4-aminobenzoate, ethyl 4-octyl aminobenzoate and 4-(hydroxymethyl) benzoic acid were used as novel efficient initiators of ε-caprolactone with t-BuP2 as a catalyst. Macroinitiator and Macromonomer of poly (ε-caprolactone) were synthesized with ethyl 4-octyl aminobenzoate and ethyl 4-aminobenzoate as initiators to afford polyamide-block-poly (ε-caprolactone) and polyamide-graft-poly (ε-caprolactone) by chain growth condensation polymerization (CGCP). In the third project, a new study has been done on chain growth condensation polymerization to discover the probability to synthesize new polymers and studied their thermal properties. For this purpose, poly (N-cyclohexyl-p-aminobenzoate) and poly (N-hexyl-p-aminobenzoate) were synthesized with low polydispersity and controlled molecular weights.