通过差示扫描量热法(DSC)和扫描电子显微镜(SEM)对双峰高密度聚乙烯(BHDPE)/低密度聚乙烯(LDPE)共混物在不同热压历史条件下的结晶行为和结晶形态进行了研究.实验结果表明,高压下的大分子链更易进行有序排列并形成较高完善度的晶体,当样品在不同的冷却方式下结晶,淬冷能大大促进共结晶的发生,在缓慢冷却条件下则不容易形成共晶,SEM拍摄的照片显示:不同热压历史条件下BHDPE/LDPE所形成的结晶形态完全各异。
Using the DSC and SEM method, the crystallization behaviors and crystalline morphologies of bimodal polyethylene and its blends with different thermal and pressure histories were studied. The DSC experimental results showed that maeromoleeule chains are prone to form more perfect crystal when crystallized from melt at high pressure. After samples crystallized using different cooling method, it's indicated that co-crystallization is increased by quenching, while retarded by slowly cooled. Samples are etched using KMnO4 etching procedures, the SEM micrographs showed that the crystalline morphologies of bimodal polyethylene and its blends with different thermal and pressure histories are differ from each other completely.