压力场和流动场同时作用下结晶性聚苯硫醚流体形成多尺度结构研究

The formation mechanism of polymer multi-scale structures under external field (like temperature field, flow field and pressure field) has always been the key scientific problem of fundamental study on organic polymer processing. Due to the high price, tough processing and high requirement for the facility, it becomes more difficult to carry out the processing study on semi-crystalline engineering polymers with rigid macromolecular chains (like polyphenylene sulfide (PPS)). Under such circumstances, the processing theory of polymers with rigid macromolecular chains falls far behind that of polymers with flexible macromolecular chains, which severely obstructs the property promotion and application extension of semi-crystalline engineering polymers. In this project, we plan to choose PPS, which has a simple component, as a representative for semi-crystalline engineering polymers with rigid macromolecular chains, then to systematically carry out the fundamental research on the formation and manipulation of multi-scale structures under the sole and coexistent effect of pressure field and flow field, including the evolution mechanism and formation dynamics of crystal structures, manipulation of specific crystal structures and morphologies as well as the exploration of the relationship between crystal structures and properties. The disclosure of relationship between crystal structures and external fields will provide theoretic guides for the acquisition of specific crystal structures and morphologies using external fields and lay the good foundation for PPS property promotion. This project will also pave the way for the processing of polymers with rigid macromolecular chains and provide the reliable theory basis for their structure manipulation.

加工外场（温度场、流动场和压力场等）下高分子多尺度结构的形成机理一直是有机高分子材料加工基础研究的核心科学问题。由于具有刚性高分子链的结晶性工程塑料（如：聚苯硫醚（PPS））价格高、成型难度大且对设备要求高，使其加工研究入门级别较高，从而导致其加工理论远远滞后于聚乙烯等柔性高分子链聚合物，这严重阻碍了结晶性工程塑料性能的提升及应用领域的拓展。本项目拟选用PPS这一结构组成简单的结晶性刚性高分子链聚合物，系统开展其在压力场与流动场单独和同时作用下多尺度结构生成与控制的基础研究，包括：晶体结构的形成演变机理与生成动力学、特定晶体结构形态的调控及晶体结构形态与宏观性能的关系的探索，从而建立晶体结构与加工外场之间的关系，为利用加工外场获得特定晶体结构形态提供理论指导，为PPS性能提升奠定良好的基础。本项目还将为刚性高分子链聚合物加工做好铺垫，为刚性高分子链聚合物的结构调控提供可靠的理论依据。

加工外场下高分子多尺度结构的形成机理一直是有机高分子材料加工基础研究的核心科学问题。由于具有刚性高分子链的聚苯硫醚（PPS价格高、成型难度大且对设备要求高，使其加工研究入门级别较高，从而导致其加工理论远远滞后于聚乙烯等柔性高分子链聚合物，这严重阻碍了结晶性工程塑料性能的提升及应用领域的拓展。.本项目通过研究PPS在压力场与流动场单独和同时作用下多尺度结构生成与控制演变过程，揭示了压力、剪切速率、剪切时间、等温结晶温度等外场参数对于PPS结晶度、片晶厚度、取向度等晶体微观多尺度结构的影响规律，建立了晶体结构与加工外场各参数之间的内在关系；基于PPS样品摩擦系数、磨损率以及摩擦磨损形貌等摩擦性能的充分研究，建立了外场作用下的聚集态结构与摩擦性能之间的关系；通过调控压力场，实现了PPS及其复合材料的高性能化与功能化，制备出系列高导热、高耐磨等的聚苯硫醚复合材料。上述研究成果可为利用加工外场赋予PPS特定晶体结构与形态提供理论指导，为PPS性能提升奠定良好的基础，拓展了其应用领域。本项目还可为刚性高分子链聚合物的结构调控提供可靠的理论依据。通过本项目的开展在Macromolecular Rapid Communications, Composites Part B等国内外核心期刊上发表学术论文11篇，SCI收录11篇；申请发明专利7项。培养了博士研究生1名，硕士研究生6名。