Molecular Studies on Polymer Gels

聚合物凝胶的分子研究

基本信息

批准号：
63044083
负责人：
NOMURA Shunji
金额：
$ 4.16万
依托单位：
Kyoto Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1990
项目状态：
已结题

项目摘要

Structure, solgel transition behavior, and dynamic aspects of polymer gels were investigated in terms of small angle neutron scattering (SANS), viscometry, forced Rayleigh scattering (FRS), fluorescence depolarization methods, and ultrasonic spectrosopy. Topological features of polymer gels were also studied by generating bimodal networks.SANS of poly (vinyl alcohol) (PVA) solutionsThe correlation length, xi, was estimated from a generalized Zimm plot for fractals having the fractal dimension of D. The variation of xi with temperature showed a gel-to-sol transition. The scattered intensity functions for the gels at different temperatures could be superimposed by employing reduced variables, I(q)/Cxi^3 and xiq, where C and q are the monomer concentration and the magnitude of the scattering vector, respectively.Phase behavior and solgel transition of PVA-borate complex in aqueous solutionsAt a given combination of PVA concentration and ionic strength, the system underwent a clear-opaque- … More clear transition with increasing boric acid concentration. This behavior was explained by a balance of the exclude volume effect due to intra- and inter-chain crosslinks and electrostatic potentials.Dynamical aspects of thermoreversible gelation of polymer solutionsSolutions of poly (n-butyl methacrylate) (PnBNA), poly (isobutyl methacrylate) (PiBMA), poly (tert-butyl methacrylate) (PtBMA) and poly (2-hydroxyethyl methacrylate) (PHEMA) in 2-propanol and 2-butanol were used as samples. The thermoreversible gelation mechanism of poly (butyl methacrylate)/2-propanol solutions strongly depends on the chemical structures of their isomers. It was also found that the elastic energy that is generated by the chemical gelation of polystyrene (PS) chains in a binary mixture of PS and poly (2-chlorostyrene) (P2CS), modifies the concentration fluctuations of PS/P2CS mixtures.Bimodal Polymer NetworksComputer simulations were performed on two and three dimensional square lattices with tetrafunctional crosslinks. The simulated networks demonstrated the presence of appreaciable of number of network imperfections, such as unsatisfied crosslinks (chain extenders), isolated chains, unreacted crosslink agents, and dangling chains. It was found that the simulated chains re-produced several topological features of real elastomers. Less

根据小角度中子散射（SANS），粘度计，强迫瑞利散射（FRS），荧光沉积方法和超声谱图，研究了聚合物凝胶的结构，溶液过渡行为和动态方面。聚合物凝胶的拓扑特征也通过产生双峰网络进行研究。聚（乙烯基醇）（PVA）溶液的sans从广义的ZIMM图中估计了具有D的分形的ZIMM图。XI的分形尺寸。XI的变化显示了温度到温度的凝胶到溶质过渡。在不同温度下，凝胶的散射强度功能可以通过使用降低的变量，I（Q）/CXI^3和XIQ叠加，其中C和Q是单体浓度和散射载体的大小，并且相应的行为和pVA溶液中PVA浓度的pVA浓度和pVA浓度的solgel blocation和pva浓度的溶解度和溶解度均为PVA组合和PVA综合综合体系。透明 - 更清晰的过渡，硼酸浓度的增加。通过链内和链间交联和静电电位的排除体积效应的平衡来解释这种行为。聚合物溶液在聚合物溶液（N-丁基甲基丙烯酸酯）（PNBNA）（PNBNA）（PNBNA），聚（PIBMA）（PIBMA），聚甲基丙烯酸酯（PTERBMA），聚甲基丙烯酸酯（PTBMA），聚甲基丙烯酸酯（PTBMA），聚甲基丙烯酸酯）的Y型动力学方面（2-羟基乙基甲酯）（phema）在2-丙醇和2-丁醇中用作样品。聚（丁基甲基丙烯酸丁酯）/2-丙醇溶液的热凝胶机制很大程度上取决于其异构体的化学结构。还发现，在PS和聚（2-氯苯乙烯）（P2C）的二进制混合物中，聚苯乙烯（PS）链的化学凝胶产生的弹性能改变了PS/P2CS混合物的浓度波动。bimimalosoptusternetscomputer网络（bimodal Poctutustures）在两个和三差方面进行了crossiontional crossionitiont crosslra intraine tirra latt。模拟网络证明了网络缺陷次数的数量很少，例如不满意的交联（链延长），孤立的链条，未反应的交叉链接剂和悬挂链。发现模拟的链条重新生产了真实弹性体的几个拓扑特征。较少的