中文摘要：

探讨了多流体多次注射成型过程中剪切场和温度场对聚合物制品形态结构的影响.采用流变测试仪测试了高密度聚乙烯（HDPE）的流变参数并通过计算得到其松弛时间,借助扫描电子显微镜（SEM）对气体辅助注射成型（GAIM）和不同模壁温度下多熔体多次注射成型（MMMIM） HDPE制品的一次注射熔体相形态结构进行了表征分析.结果发现,制品形态比普通注射制品出现了更加丰富的形态结构（球晶、串晶和片晶等）,尤其是MMMIM出现了双皮芯结构.适当的冷却速率与松弛时间匹配时,有利于链段运动而产生丰富的形态结构,同时又能把这种结构尽量地保留下来.

英文摘要：

This paper discussed the influence of shear field and temperature field by multi-injection molding of multi-fluids to morphological structure of polymer injection parts. The rheological parameters of high density polyethylene （HDPE） were tested by rheometer and the relaxation time was obtained by calculation. With the aid of scanning electron microscope （ SEM）, we studied morphological structure of the first injection melt in polymer injection parts of gas assisted injection molding （GAIM） and multiple melt injection molding under different mold temperature （MMMIM）. The product appeared more rich morphological structure （spherulite, shish-kebab and lamellaestrueture, etc. ） than ordinary injection products, especially MMMIM appeared double skin-core structure. When the appropriate cooling rate and relaxation time were matched, it was advantageous to the chain segment motion to get a rich morphological structure and try to make the structure be retained at the same time.