酚酞型聚芳醚砜(Ⅶ):K_2C0_3存在下PP/DCDPS体系聚合反应机理的研究

利用~(13)C-NMR方法研究了弱碱K_2CO_3存在下酚酞成盐反应及其与活性双卤砜亲核缩聚反应过程中的结构特征。对一系列碱性条件下酚酞(PP)与4,4'-二氯二苯砜(DCDPS)的缩聚反应的研究表明任何影响内酯结构酚酞盐生成的因素都会严重阻碍聚合反应的进行。对模型化合物存在下K_2CO_3在极性非质子溶剂中的溶解/解离行为的研究结果表明酚酞类Card。双酚与固体K_2CO_3之间可能存在着一种特殊的络合作用。基于我们系列研究结果,本文中总结提出了弱碱K_2CO_3存在下酚酞的反应机理。     

Synthesis of L-Lysine and L-Glutamic Acid Derivatives with Long Alkyl Chains and Polycondensation of Langmuir-Blodgett Films

Two esters of L-lysine and L-glutamic acid containing long alkyl groups were synthesized and their polycondensation in monolayers and multilayers was investigated. The pressure-area isotherms of the ester of L-lysine depend markedly on the time of residence at the air-water interface. The change of FT-IR spectra of the deposited film, which can be lifted as a Z-type film, indicates that polycondensation can occur in the monolayer at 10°C without any treatment. The spectrum of the film cast from chloroform hardly changed with time. These results lead to the conclusion that a regular arrangement of monomer molecules in the monolayer, where the amino and ester carbonyl groups are concentrated, is more suitable for the polycondensation. The ester of L-glutamic acid can also form stable monolayers which can be easily deposited on a hydrophobic plate as a Y-type film by the Blodgett technique. The polycondensation of multilayers under an atmosphere of triethylamine was investigated by IR spectroscopy. It indicates that the condensation in multilayers proceeds via intermolecular and intramolecular reactions, by which poly(L-glutamate) derivatives and 2-pyrrolidone derivatives are formed, respectively. The condensation in the bulk crystalline powder gives exclusively the 2-pyrrolidone derivative by intramolecular reaction. These results suggest that the monomer molecules in the multilayers are favorably aligned for the intermolecular reaction, in contrast to the situation in the bulk crystalline powder.     

酚酞型聚芳醚砜——Ⅱ.侧基结构对Cardo双酚聚合反应性的影响

基于在“一步法”聚合反应过程中发现的酚酞对反应有特殊的“自催化”作用,本文合成了几种具有与酚酞类似结构的Cardo双酚,并通过对其聚合反应规律的研究,进一步探讨“自催化”作用的本质。实验结果表明,这类Cardo双酚也较普通结构双酚更易于进行异相成盐反应,表现为其聚合反应速度的明显加快。     

酚酞型聚芳醚砜共聚物的合成和结构及热性能研究

<正> 聚芳醚砜是一类具有重要发展前景的高分子材料.合成带有酞侧基的僵硬链高分子,可提高其玻璃化转变温度,是获得耐热高分子的一种途径.最近,刘克静等从改进合成技术,使酚酞型聚芳醚砜的生产有了现实性.并且发现在改进的聚合条件下,酚酞表现出类似“自催化”的作用,能使聚合反应速度明显加快.其反应机理正在研究中. 本文为进一步验证酚酞的特殊反应性,了解因酚酞介入的共聚反应行为及其对聚合物结构和性能的影响,提高普通聚芳醚砜的使用温度或改善其流动性,设计合成了酚酞与几种不同结构双酚的共聚物.并对其结构和性能关系进行了探讨.本文报道了对共聚物     

SPEEK/PES嵌段聚合物的制备及性能

本文首先合成具有易磺化链段/难磺化链段的嵌段共聚物, 再通过温和的后磺化方法, 制备磺化聚醚醚酮/聚醚砜(SPEEK/PES)嵌段聚合物, 初步研究了膜的微观形貌和性能.