摘要
用欠焦电子显微术和电子衍射技术研究了降温速率对高密度聚乙烯(HDPE)在全同立构聚丙烯(iPP)上附生结晶的影响.HDPE在高取向iPP基质膜上的附生生长仅发生在HDPE与iPP的直接接触面上,存在一临界附生层厚度,超出这一厚度的HDPE与iPP无取向附生关系.降温速率不影响附生层内的HDPE与iPP的附生结构关系,但对iPP基质膜上附生生长的HDPE的厚度,即HDPE的临界附生层厚度有明显影响.在缓慢降温(0.5℃/min)条件下,HDPE在iPP上的附生层厚度约为100nm.而室温空气降温条件下,HDPE在iPP上的附生层厚度则为250nm.
ffects of cooling rates on the epitaxy of high-density polyethylene(HDPE) on isotactic polypropylene(iPP)substrate film have been studied by TEM and electron diffraction. The results of electron microscopy and electron diffraction indicate that epitaxial nucleation and growth of HDPE on oriented iPP substrate take place only on the direct contact plane of HDPE with iPP.There exists a critical epitaxial thickness of HDPE on iPP film.The thickness of epitaxial interface layer is strongly affected by the cooling rate of HDPE after heat treatment.During slow cooling process, three layers of crystalline structure of HDPE are formed.The thickness of critical epitaxial layer is about 100urn.Fast cooling rate results in the formation of two layer crystalline structure.The thickness of critical epitaxial layer is about 250nm.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
1995年第5期535-541,共7页
Acta Polymerica Sinica
基金
国家自然科学基金
关键词
聚丙烯
聚乙烯
附生结晶
降温速率
Polypropylene,Polyethylene,Epitaxial crystallization,Morphology