高密度聚乙烯(HDPE)在静高压下的结晶研究

STUDIES OF CRYSTALLIZATION OF HIGH DENSITY POLYETHYLENE UNDER HIGH HYDROSTATIC PRESSURE

高密度聚乙烯(HDPE) 在 1GPa-2GPa的静高压下发生熔体结晶。实验中HDPE 从熔融态以5℃/min的速率冷却。对经过高压处理后的样品在大气压下进行了DSC,SEM和WAXD测量。测量结果表明,高压后的HDPE的结晶度由原来的8.2％提到89.9％。<10>方向的伸直链片晶平均厚度也由原来的14nm加厚为25nm。DSC和SEM的观察结果证实了伸直链晶体的存在,静高压和温度的控制是形成PE伸直链晶体的关键。

High density polyethylene has been crystallized under a pressure 1GPa to 2GPa and cooled at 5 'C per minute from the melting point.The solids were analyzed at atmosphere pressure by DSC, SEM and WAXD. The data show that the crystalline content of the samples by WAXD increases to 89.9% from 68.2% of the original material. Extended chain lamellae have thickened from 14 nm to 25nm. DSC and SEM observations show the existence of the extended chain lamellae. Controlling of high pressure and temperature is the kay of the formation of extended-chain crystals.