流变和光学法研究PAN/DMSO/H_2O体系的凝胶化和相分离行为  

Rheological and Optical Investigation of the Gelation and Phase Separation Behavior for PAN/DMSO/H_2O System

作　　者：莫高明[1] 王艳菲[1] 张若愚[1] 杨建行[1] 何流[1] 

机构地区：[1]中国科学院宁波材料技术与工程研究所,宁波315201

出　　处：《高分子通报》2016年第9期162-170,共9页Polymer Bulletin

基　　金：国家自然科学基金青年项目(21204096)

摘　　要：碳纤维是非常重要的增强材料,在军工以及高档民用产品中用途广泛。因为聚丙烯腈原丝的结构会"遗传"到最终的碳纤维结构中,因此原丝结构对碳纤维的性能影响很大。原丝的结构是纺丝液在凝固浴中的相分离和凝胶化两个过程决定的,因此研究这两个过程的规律并进一步控制它们的进程,达到调控原丝结构的目的是非常重要的。本文介绍了本课题组利用流变学及光学的方法研究PAN/DMSO/H2O体系凝胶化及相分离行为的最新研究成果,主要探索了PAN/DMSO/H2O浓溶液中凝胶化行为,发现了二次自相似结构的形成并对其机理进行了分析,并对PAN/DMSO/H2O亚浓溶液中凝胶化与相分离的耦合过程进行了研究,分析了最终凝胶的结构特性及Winter-Chambon模型在此过程中的适用性。最后,对PAN/DMSO/H2O体系凝胶化及相分离行为的下一步研究进行了展望。Carbon fiber is a very important material that can reinforce other materials like polymers, and it is widely used in military weapons and high-end products. Since the structure of the original PAN fiber will propagate to that of final carbon fiber, the quality and performance of carbon fibers are largely depended on the preparation of PAN fiber. The phase separation and gelation processes during the solidification of PAN fiber decide its ultimate structure. Therefore, clarification of the mechanism of these two processes would benefit the control of the PAN fiber structure. In this feature article, we report the newly discovered results in PAN/DMSO/H20 blends by using rheology and optical method. We find the second self-similar structure in PAN concentrated system and the underlying mechanism is also discussed. We also analyze the coupling of the phase separation and gelation in semi-dilute PAN concentration system, besides we also predict and explain the non-uniform structure of the resulted gel. Validity of the Chambon-Winter model is also confirmed in such phase separated system. At last, we forecast the future work on the PAN/DMSO/H2O blends.

关 键 词：聚丙烯腈 凝胶化 相分离 流变 光学显微镜 

分 类 号：TQ342.742[化学工程—化纤工业]