高密度聚乙烯等温结晶的流变行为  

Rheological behavior of isothermal crystallization for high-density polyethylene

作　　者：廖华勇[1] 林渊[1] 范毓润[1] 

机构地区：[1]浙江大学流体传动及控制国家重点实验室,浙江杭州310027

出　　处：《化工学报》2007年第10期2500-2505,共6页CIESC Journal

基　　金：国家自然科学基金项目(10472105);教育部博士点专项基金项目(20050335050)~~

摘　　要：Isothermal crystallization behavior of high-density polyethylene (HDPE) was studied experimentally by using a rotary rheometer with parallel plates fixtures.It was found that the crystallization rate depended on the surface roughness of the fixtures with the same chemical composition.As the surface roughness increased,the crystallization rate first increased then decreased which meant that there was a range of surface roughness where the crystallization rate could reach a maximum value.Surface roughness effectively enhanced the interfacial area and decreased heat resistance, but possibly trapped air pockets in the valley of the rough surface produced a considerable interfacial heat resistance,both affecting the crystallization rate of HDPE.The isothermal crystallization rate decreased in sequence as the HDPE specimen contacted with aluminum,brass and stainless steel plates whose surface roughness were on the same level.The sample crystallizes more quickly on the fixtures with higher heat conduction coefficient, thus lowering heat resistance.Isothermal crystallization behavior of high-density polyethylene （HDPE） was studied experimentally by using a rotary rheometer with parallel plates fixtures. It was found that the crystallization rate depended on the surface roughness of the fixtures with the same chemical composition. As the surface roughness increased, the crystallization rate first increased then decreased which meant that there was a range of surface roughness where the crystallization rate could reach a maximum value. Surface roughness effectively enhanced the interracial area and decreased heat resistance, but possibly trapped air pockets in the valley of the rough surface produced a considerable interracial heat resistance, both affecting the crystallization rate of HDPE. The isothermal crystallization rate decreased in sequence as the HDPE specimen contacted with aluminum, brass and stainless steel plates whose surface roughness were on the same level. The sample crystallizes more quickly on the fixtures with higher heat conduction coefficient, thus lowering heat resistance.

关 键 词：高密度聚乙烯 等温结晶 表面粗糙度 热阻 表面能 

分 类 号：TQ026.5[化学工程]