高密度聚乙烯/硅烷偶联剂改性硫酸钙晶须复合材料的制备与性能

Preparation and properties of HDPE/silane coupling agent modified calcium sulphate whiskers composites

以γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)改性的硫酸钙晶须(CSW)为高密度聚乙烯(HDPE)的填料,采用熔融共混法制备了HDPE/CSW复合材料。通过SEM、XRD、TG、DSC表征了KH570改性的CSW对复合材料HDPE/CSW的性能影响。结果表明,改性CSW质量分数为20%时,HDPE/CSW的拉伸和弯曲强度比纯HDPE分别增加9.28%和33.04%,且易产生异相结晶,提升了HDPE/CSW复合材料的耐热性和结晶度。纯HDPE的热降解反应活化能为244.11 k J/mol,改性CSW质量分数为50%时,HDPE/CSW复合材料的热降解反应活化能降到236.99 kJ/mol,表明CSW提升了HDPE/CSW复合材料的热降解反应速率,扩展了复合材料的使用范围。

High density polyethylene(HDPE)/calcium sulphate whiskers(CSW)composites were prepared from melt blending of HDPE andγ-methacryloxypropyltrimethoxysilane(KH570)modified CSW.The influence of KH570 modified CSW on the properties of HDPE/CSW composites were then analyzed by SEM,XRD,TG and DSC.The results showed that the HDPE/CSW composites with 20%(mass fraction)CSW exhibited an increase in tensile and flexural strengt h by 39.51%and 15.9%,respectively,in comparison to pure HDPE.Meanwhile,the HDPE/CSW composites were prone to heterogeneous crystallization,which enhanced the heat resistance and crystallinity of the composites.Moreover,data from crystallization behavior analysis indicated that the crystal growth in HDPE/CSW composites was in two-dimensional sheets.The activation energy of thermal degradation reaction of pure HDPE was 244.11 kJ/mol,while that of HDPE/CSW composites with 50%(mass fraction)CSW decreased to 236.99 kJ/mol,indicating that CSW enhanced the thermal degradation reaction rate and extended the application range of the composites.