高聚物“结构控制”加工成型工艺研究进展

Polymer "structure controlling" molding process

综述了不同的聚合物加工工艺,包括新型注射成型工艺、多层共挤出工艺、原位微纤化成型工艺等,这些新型高分子加工工艺可以使高聚物的结构、形态更加有序,得到综合性能更加优异的高聚物制品。采用新型注射成型工艺制备的产品最大的特点是具有"皮层-芯层"结构,芯层处高分子的取向度低于皮层处,由于皮层很薄,因此,整个制品的平均取向度较低。多层共挤出工艺可以直接得到不同种类、不同性能的多层高聚物复合在一起的制品,可以根据需求设计不同结构、层厚、层数的产品,该工艺具有良好的调控性,制备的产品具有明确的、可控的结构与层次,是可以对高聚物进行"结构化"加工的工艺技术。原位微纤化成型工艺主要用来提高材料的力学性能,利用分散相的取向变形实现,同时改变高聚物的结晶行为。

This paper provides an overview of polymer processing processes involving new type injection molding, multilayer co-extrusion and in situ microfibrillar molding. These processes can be used to help the structure and morphology of the polymer be better organized and obtain products with excellent properties. Among which, the polymer prepared by new type injection molding features ＂skin-core＂ structure, the orientation degree of the macro-molecules at the core is lower than that of the ones at the skin, therefore the average orientation degree of the product is low due to the thin skin. Multilayer co-extrusion is applied to fabricate the product eomposited with various multilayer polymers of diversified properties. It can also be used to design the product with different structures, thickness and number of layers to meet the requirements of the customers. The good control of the process contributes to the explicit and controllable structure and layers of the product, which has implemented ＂structural processing＂ for polymer. The polymer produced by in situ mierofibrillar molding is improved in mechanical properties through orientation deformation of the disperse phase. The crystallization behavior of the polymer is changed as well.