No description available.

The objective of this study was to compare different modifiers in two asphalt cements, namely Cold Lake 80/100 obtained from the Edmonton, Alberta refinery of Imperial Oil Limited and a PG 58-28 obtained from a now closed refinery in the Montreal, Quebec area. The modifiers investigated were polyphosphoric acid (PPA), styrene-butadiene-styrene (SBS), and reactive ethylene terpolymer (Elvaloy® RET). The comparisons were done based on both unaged and laboratory-aged materials. The investigation covers high temperature grading using a dynamic shear rheometer (DSR), low temperature grading using a bending beam rheometer (BBR), ductile strain tolerance as measured in the double-edge-notched tension (DENT) test and percentage recovered strain using multiple shear creep recovery (MSCR) test. The Superpave® performance grade span was increased for all modifiers with substantial increases in the high temperature rutting parameter G*/sin while the BBR parameters, T(S = 300 MPa) and T(m = 0.3), remained largely unchanged. In the PG 58-28 base asphalt, Elvaloy® modifiers were able to reduce the intermediate Superpave® grade temperature by significant amounts. All polymer modifiers were good at improving the ductile strain tolerance as measured in the DENT test. In contrast, PPA alone reduces the strain tolerance due to the formation of extra asphaltenes and the likely gelation of the asphaltene-rich phase. Nearly all the modified samples passed the MSCR test except those with poor compatibility (i.e. SBS blended with Cold Lake without sulfur, Elvaloy® systems without acid catalyst, and pure PPA modified systems) or no modifier, which did not reach the required elastic recovery at high levels of non-recoverable compliance. In the BBR test done at low temperatures, all modified systems showed similar elastic recovery and viscous (non-recoverable) compliance. However, in the ductile-to-brittle range the Elvaloy® RET-modified binders showed a definite advantage of a few degrees over the unmodified base asphalts. Finally, chemical aging tendencies, as measured by weight gain and carbonyl formation, turned out to be very similar for all the investigated compositions. / Thesis (Master, Chemistry) -- Queen's University, 2010-12-13 13:29:45.173

The structure property behavior of an ethylene-propylenediene ionic terpolymer containing varying amounts of ZnSt was investigated. Studies show that ZnSt acts as a reinforcing filler under ambient conditions. Stress-strain behavior, percent relaxation, hysteresis and permanent set were all found to increase with increasing ZnSt content. Increases in stress values upon annealing for all samples were attributed to increased ionic domain formation and growth. Aging was found to alter stress values at elongations beyond the elastic region. SAXS data indicates that structural rearrangement occurs with aging. DSC studies confirmed the effects of aging in that a difference occurred in thermal behavior between 1st and 2nd meltings. DSC also indicated the presence of an impurity, which is believed to be stearic acid. Water absorption studies conducted on the aged systems suggested that ZnSt either interacts with the Zn salt group tying up absorption sites or diffuses towards Zn salt groups as possible nucleation sites and forms a water barrier. Water negatively affects ZnSt's ability to act as a reinforcing filler. A rise in SOC values indicated non-Gaussian behavior for all samples. WAXS indicates that a portion of the ZnSt crystals hold their orientation upon stress release. The ZnSt loaded and unloaded systems had distinctly different morphologies. Both SEM and WAXS studies of the 303-50 sample indicated small ZnSt particles of less than 400°A in size. Comparison with modulus studies of other hard phase systems lent major support to the postulation of very small ZnSt crystals. / Master of Science

A photolabile terpolymer containing 6-nitroveratyloxycarbonyl (NVOC) protected amine, epoxy and trimethoxysilyl functionality in 1:3:2 monomer ratio was synthesized to template glass surfaces for specific site directed coupling of non-probe oligomers and probe oligonucleotides. Non-probe oligomers were introduced to the surface to control the environment of the probes by reducing probe-to-probe and probe-to-surface interactions. The trimethoxysilyl group served as the anchoring site for the terpolymer to be covalently bound to glass and silicon wafers. Amine terminated non-probe oligomers were coupled to the epoxy sites and thiolated 19-mer SMN1 probes were directed to the deprotected amine sites via the heterobifunctional linker, sulfosuccinimidyl-4-[maleimidomethyl]cyclohexane-1-carboxylate (sulfo-SMCC). Characterization of the terpolymer was done using 1H NMR, 13C NMR, MALDI-ToF and elemental analysis. NVOC deprotection was monitored by UV absorption, and surface characterization of the bound terpolymer on silicon wafers was investigated with XPS, ToF-SIMS, ellipsometry and static contact angle. Neutral polyethylene glycol (PEG), negatively charged methacrylic acid (MAA) oligomer and dC20 oligonucleotides were used as non-probe oligomers. The probe density on the surface was estimated to be 2.2 ± 0.3 x 10^12 molecules/cm2 and the presence of the oligomers on the surface did not significantly affect probe immobilization efficiency. The mixed films were functional for target hybridization and its selectivity towards partially-mismatched targets was investigated at different solution pH, ionic strength and temperature. It was demonstrated that pH can be tuned to ameliorate non-specific adsorption and ionic strength governed the selectivity of the surfaces. Improved selectivity was achieved at high salt concentration (1 M NaCl) on PEG and dC20 mixed films at room temperature. The MAA surface did not show significant improvements in selectivity. This indicated that charge of the oligomers does not dominate control of selectivity. The results suggested that the terpolymer construct played a role in depression of the melting temperature of the hybridized duplex to within 5 to 10 oC of room temperature. With the melting temperature shifted closer to room temperature, it is possible to improve selectivity for room temperature detections of single nucleotide polymorphism.

The phenomenon of depropagation or reverse polymerization for multicomponent polymerizations has been studied in detail. The monomer Alpha-Methyl Styrene (AMS) has been copolymerized with Methyl Methacrylate (MMA) and Butyl Acrylate (BA) at temperatures ranging from 60oC to 140oC and the kinetics have been studied in the form of propagation/cross propagation and depropagation parameters. There have been multiple attempts with varying amounts of success in the past to determine the kinetic parameters for depropagating systems including work by Lowry and Wittmer as well as other modelling methodologies that are not as mechanistic. The most recent development of the mechanistic terminal model is that of the Kruger model. The model is robust and can take into account all special cases as well as all reactions being reversible. The kinetic parameters have been estimated for each of the three binary systems using the Kruger model (MMA/AMS, MMA/BA, BA/AMS). The Alfrey-Goldfinger model is inadequate to describe depropagating terpolymer systems and in order to study them, a new model was developed based upon the binary Kruger model. This new model takes into account a fully depropagating terpolymer system leading to a total of 15 parameters to be estimated. These 15 parameters have the same definitions as those estimated from the binary Kruger model, thus making accurate analysis of the binary systems crucial since these will be used as first estimates for the terpolymer system. Extensive experimental data (composition, conversion and molecular weights) was collected and analysed for the MMA/AMS and BA/AMS systems. For the BA/AMS system both the bulk and solution copolymerizations were studied in detail with the results from the Kruger model not showing a significant difference in the reactivity ratios between the two types of polymerization. For the MMA/AMS system, a bulk study only was done which revealed an interesting phenomenon that points toward a break down of the long chain approximations used for all of the models being studied. For both of these systems, extensive ¹H NMR analysis was done to determine the copolymer composition. Data collected in previous research for the MMA/BA system was reanalysed using the Kruger model and it was found that the parameter estimates did not differ significantly from the published values. Extensive benchmarking was done with the newly developed terpolymer model on non-depropagating systems using data from the literature to ensure it worked for the simplest cases. It was found that the model matched the parameter estimates from the literature and in some cases improving upon them to fit the data better. Along with the benchmarking a sensitivity analysis was done which revealed some interesting information. For the MMA/BA/AMS terpolymer system a set of experiments (based upon practical considerations) were performed and the composition of the polymer was determined using ¹³C NMR instead of the usual ¹H NMR due to the difficulty of peak separation for the complex terpolymer. Using the depropagating terpolymer composition data in conjunction with the parameter estimates from the three binary systems allowed for estimation of the 15 kinetic parameters, which showed only minor variation from the binary estimates.

The phenomenon of depropagation or reverse polymerization for multicomponent polymerizations has been studied in detail. The monomer Alpha-Methyl Styrene (AMS) has been copolymerized with Methyl Methacrylate (MMA) and Butyl Acrylate (BA) at temperatures ranging from 60oC to 140oC and the kinetics have been studied in the form of propagation/cross propagation and depropagation parameters. There have been multiple attempts with varying amounts of success in the past to determine the kinetic parameters for depropagating systems including work by Lowry and Wittmer as well as other modelling methodologies that are not as mechanistic. The most recent development of the mechanistic terminal model is that of the Kruger model. The model is robust and can take into account all special cases as well as all reactions being reversible. The kinetic parameters have been estimated for each of the three binary systems using the Kruger model (MMA/AMS, MMA/BA, BA/AMS). The Alfrey-Goldfinger model is inadequate to describe depropagating terpolymer systems and in order to study them, a new model was developed based upon the binary Kruger model. This new model takes into account a fully depropagating terpolymer system leading to a total of 15 parameters to be estimated. These 15 parameters have the same definitions as those estimated from the binary Kruger model, thus making accurate analysis of the binary systems crucial since these will be used as first estimates for the terpolymer system. Extensive experimental data (composition, conversion and molecular weights) was collected and analysed for the MMA/AMS and BA/AMS systems. For the BA/AMS system both the bulk and solution copolymerizations were studied in detail with the results from the Kruger model not showing a significant difference in the reactivity ratios between the two types of polymerization. For the MMA/AMS system, a bulk study only was done which revealed an interesting phenomenon that points toward a break down of the long chain approximations used for all of the models being studied. For both of these systems, extensive ¹H NMR analysis was done to determine the copolymer composition. Data collected in previous research for the MMA/BA system was reanalysed using the Kruger model and it was found that the parameter estimates did not differ significantly from the published values. Extensive benchmarking was done with the newly developed terpolymer model on non-depropagating systems using data from the literature to ensure it worked for the simplest cases. It was found that the model matched the parameter estimates from the literature and in some cases improving upon them to fit the data better. Along with the benchmarking a sensitivity analysis was done which revealed some interesting information. For the MMA/BA/AMS terpolymer system a set of experiments (based upon practical considerations) were performed and the composition of the polymer was determined using ¹³C NMR instead of the usual ¹H NMR due to the difficulty of peak separation for the complex terpolymer. Using the depropagating terpolymer composition data in conjunction with the parameter estimates from the three binary systems allowed for estimation of the 15 kinetic parameters, which showed only minor variation from the binary estimates.

A photolabile terpolymer containing 6-nitroveratyloxycarbonyl (NVOC) protected amine, epoxy and trimethoxysilyl functionality in 1:3:2 monomer ratio was synthesized to template glass surfaces for specific site directed coupling of non-probe oligomers and probe oligonucleotides. Non-probe oligomers were introduced to the surface to control the environment of the probes by reducing probe-to-probe and probe-to-surface interactions. The trimethoxysilyl group served as the anchoring site for the terpolymer to be covalently bound to glass and silicon wafers. Amine terminated non-probe oligomers were coupled to the epoxy sites and thiolated 19-mer SMN1 probes were directed to the deprotected amine sites via the heterobifunctional linker, sulfosuccinimidyl-4-[maleimidomethyl]cyclohexane-1-carboxylate (sulfo-SMCC). Characterization of the terpolymer was done using 1H NMR, 13C NMR, MALDI-ToF and elemental analysis. NVOC deprotection was monitored by UV absorption, and surface characterization of the bound terpolymer on silicon wafers was investigated with XPS, ToF-SIMS, ellipsometry and static contact angle. Neutral polyethylene glycol (PEG), negatively charged methacrylic acid (MAA) oligomer and dC20 oligonucleotides were used as non-probe oligomers. The probe density on the surface was estimated to be 2.2 ± 0.3 x 10^12 molecules/cm2 and the presence of the oligomers on the surface did not significantly affect probe immobilization efficiency. The mixed films were functional for target hybridization and its selectivity towards partially-mismatched targets was investigated at different solution pH, ionic strength and temperature. It was demonstrated that pH can be tuned to ameliorate non-specific adsorption and ionic strength governed the selectivity of the surfaces. Improved selectivity was achieved at high salt concentration (1 M NaCl) on PEG and dC20 mixed films at room temperature. The MAA surface did not show significant improvements in selectivity. This indicated that charge of the oligomers does not dominate control of selectivity. The results suggested that the terpolymer construct played a role in depression of the melting temperature of the hybridized duplex to within 5 to 10 oC of room temperature. With the melting temperature shifted closer to room temperature, it is possible to improve selectivity for room temperature detections of single nucleotide polymorphism.

Orientador: Maria Isabel Felisberti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-17T19:50:50Z (GMT). No. of bitstreams: 1 Trinca_RafaelBergamo_M.pdf: 2663870 bytes, checksum: 36c96b7a317207cfd922f61029873b60 (MD5) Previous issue date: 2011 / Resumo: Neste trabalho foram sintetizados copolímeros bi (triblocos) e tricomponentes (penta blocos) constituídos de poli(etileno glicol) (PEG), l-lactídeo (3,6-Dimetil-1,4-dioxano-2,5-diona - LLA) e glicolídeo (1,4-dioxano-2,5-diona - GL). A síntese foi realizada pelo método de polimerização por abertura de anel (Ring-Opening Polymerization ¿ ROP) utilizando o 2-etilhexanoato de estanho e o PEG, como catalisador e iniciador, respectivamente. No que diz respeito às contribuições do projeto, foram estabelecidas as condições reacionais para a polimerização por abertura de anel em solução de tolueno, método até então não descrito na literatura. Além disso, o estudo de ação catalítica realizado mostrou que o provável mecanismo de ação do catalisador 2-etilhexanoato de estanho envolve etapas de coordenação/inserção, sendo que eventos de transferência de cadeia são minimizados. Dessa forma, apenas os grupos iniciadores previamente coordenados ao catalisador irão participar da reação, sendo necessário o uso de razões estequiométricas entre catalisador e iniciador para se garantir a manutenção das proporções entre monômeros e iniciadores utilizadas no meio reacional. O emprego das condições catalíticas estabelecidas garante elevada conversão dos monômeros e elevado rendimento reacional. Os copolímeros sintetizados foram caracterizados por técnicas de DSC, TGA, RMN, GPC e ensaios de degradação hidrolítica e intumescimento. A cristalização dos diferentes blocos dos copolímeros foi parcial ou totalmente suprimida por razões conformacionais e de impedimento estéreo, sendo dependente da composição, arquitetura e massa molar. Copolímeros ricos em PEG são hidrossolúveis e os demais são passiveis de intumescimento em água, demonstrando o caráter anfifílico. A degradação hidrolítica ocorre preferencialmente pela cisão de ligações unindo blocos hidrofóbicos e hidrofílicos / Abstract: Copolymers and terpolymers based on poly(ethylene glycol) (PEG), l-lactide (3,6-dimethyl-1,4-dioxane-2,5-dione - LLA) and glycolide (1,4-dioxane-2,5-dione - GL) were synthesized, producing a series of triblock and pentablock polymers with different architecture and composition. The synthesis was performed by the Ring-Opening Polymerization (ROP) method, using tin(II) 2-ethylhexanoate and PEG as catalyst and initiator, respectively. Regarding to the project contributions, the reaction conditions for Ring-Opening Polymerization in toluene solution were established, method so far not described in the literature. Moreover, the study of catalytic action showed that the probable action mechanism of the catalyst tin(II) 2-ethylhexanoate involves steps of coordination-insertion, and that chain transfer events are minimized. Thus, only the initiators previously coordinated to the catalyst will participate in the reaction, being necessary the use of stoichiometric ratios between catalyst and initiator to ensure the high reaction yield and a conversion of lactones to copolymers. The copolymers were characterized by DSC, TGA, NMR and GPC techniques and by swelling and hydrolytic degradation tests. The crystallization of different blocks of the copolymers were partially or totally suppressed for conformational and steric hindrance reasons, being dependent on the composition, architecture and molecular mass. PEG-rich copolymers are water soluble and others are capable of swelling in water, showing the amphiphilic character of the copolymers. The hydrolytic degradation occurs preferentially by scission of ester bonds linking hydrophobic and hydrophilic blocks / Mestrado / Físico-Química / Mestre em Química

L’objectif premier de ce travail a été de trouver une méthode de synthèse permettant depréparer des terpolymères ABC linéaires et en étoile en gardant la masse molaire des blocs A et B(PS et P2VP) constantes, tout en faisant varier la masse molaire du bloc C (PI) de sorte à avoiraccès à différentes morphologies. Le deuxième objectif consistait en l’auto-assemblage desterpolymères synthétisés sous forme de films minces.Afin de répondre au premier objectif de cette thèse, une voie de synthèse, combinant lapolymérisation anionique avec une méthode de couplage, a été mise au point. La polymérisationanionique séquentielle des blocs PS et P2VP a donné lieu à des chaînes PS-b-P2VPfonctionnalisées qui ont été ensuite couplées à différents blocs PI via une estérification de Steglich.Cette méthode de synthèse s’est révélée pertinente car des terpolymères ABC linéaires et en étoiletrès bien définis (c-à-d ayant une dispersité inférieure à 1.1) ont pu être synthétisés. De plus, laméthode de couplage, ayant un rendement proche de 100%, ne met pas en jeu l’utilisation de métalen tant que catalyseur.Dans un deuxième temps, l’auto-organisation des terpolymères a permis d’obtenir denouvelles morphologies sous forme de films minces. Un recuit par vapeur de solvant a été utilisépour apporter de la mobilité aux chaînes terpolymères. Ainsi, nous avons montré que l’autoorganisationde chaînes terpolymères linéaires (PS-b-P2VP-b-PI) permettait la formation d’unephase double gyroid coeur-écorce en film mince. De plus, l’auto-organisation des terpolymères enétoile (3 μ-ISP) a permis d’obtenir un pavage d’Archimède de type (4.6.12) pour la première foisen film mince. Dans ce cas, nous avons aussi montré que varier la masse molaire du bloc PI ainsique la nature du solvant de recuit permettait une rotation des domaines au sein la structure.Typiquement le coeur de la structure peut être occupé soit par le PI ou bien le PS. / The first objective of this work was to develop a synthesis method enabling the preparationof linear and star ABC terpolymers. The molecular weights of the A and B (PS and P2VP) blockswere kept constant while the size of the C (PI) block was varied to achieve different morphologies.The second objective of this work was devoted to the study of the self-assembly of linear and starABC terpolymer thin films. A synthesis route combining the anionic polymerization with acoupling method was developed. The PS and P2VP blocks were synthesized by a sequential anionicpolymerization. The PI block separately synthesized by anionic polymerization was then coupledto the PS-b-P2VP diblock via a Steglich esterification. This method revealed to be efficient sinceit is a catalyst metal-free reaction enabling to achieve well-defined terpolymers with a dispersitybelow 1.1The study of star and linear ABC terpolymer self-assembly led to new morphologies in thinfilm. A solvent vapor annealing treatment was used to promote the mobility of the polymericchains. A core-shell double gyroid structure was produced from the self-assembly of linear PS-b-P2VP-b-PI thin films. Four different crystallographic planes were observed depending on the filmthickness. Moreover, the self-assembly of star ABC terpolymer chains into a thin film (4.6.12)Archimedean tilling pattern was demonstrated for the first time. Here, the PS and PI blocksoccupied different places within the (4.6.12) tiling pattern depending on the PI volume ratio andthe solvent selected to swell the film.

No description available.