高聚物成型加工过程粘弹流动诱导取向结晶机理数值模拟与实验研究

项目名称： 高聚物成型加工过程粘弹流动诱导取向结晶机理数值模拟与实验研究

项目编号： No.51205231

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 机械工程学科

项目作者： 牟玥

作者单位： 山东大学

项目金额： 25万元

中文摘要： 高聚物挤塑、注塑和吹塑等常用加工操作过程中，材料会发生由熔体向晶态结构的转变。合理控制该转变，可有效改善材料内部结构，提高制品性能。由于转变过程中存在液固两相的变化，且材料粘弹流变与取向结晶行为相互影响，其机理复杂。目前，国内外相关研究仍局限于单一尺度实验和理论分析，忽略加工外场作用影响，其结论难以指导实际成型工艺控制。为此，本项目拟系统研究无定形和半结晶两相共存体系粘弹流动诱导取向结晶理论建模方法，建立三维宏观粘弹非稳态流动与介观流动诱导取向结晶相耦合的双尺度数值模型和求解方案，结合工艺实验研究，探讨不同成型加工条件下材料宏观力学与微结构参数变化规律，揭示加工历史-形态-性能演变机理，通过合理调整成型工艺条件与模具结构，控制材料由熔体向晶态结构的转变，为成型制品结构性能优化提供指导。项目将理论研究与工艺实验相结合，旨在建立高聚物成型工艺控制关键理论和方法，具有理论研究意义和工程应用前景。

中文关键词： 高聚物；成型加工；粘弹；取向；结晶

英文摘要： The material structure usually transform from melts to crystalline state in commonly used polymer processing like extrusion, injection molding and blow molding. If the structure transformation can be reasonably controlled, the inner structure and performance of the final product can be improved. However, the corresponding mechanics is complicated for the reasons of the phase transformation phenomenon and the interaction of viscoelastic rheological and orientation crystallization behavior. The relevant research is still limited to single scale experimental and theoretical analysis that ignoring the effects of external processing field. The results are therefore difficult to afford to practical processing control. In the study, the theoretical model of viscoelastic flow induced orientation crystallization behavior of two phases including amorphous and semi-crystalline phase will be investigated. The key technology for two scale simulation of three-dimensional unsteady viscoelastic non-isothermal flow coupling flow induced orientation crystallization in polymer processing will be established. The variation characteristics of macroscopic mechanical and microstructure parameters under different processing conditions can be investigated by using the proposed simulation technology and experimental method. The evolution

英文关键词： Polymer；Processing；Viscoelastic；Orientation；Crystallization