高密度聚乙烯/硫酸钙晶须复合材料的制备及其性能

Preparation and properties of calcium sulfate whisker reinforced high-density polyethylene composites

摘要:

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等表征了KH570改性的CSW对复合材料HDPE/CSW的性能影响。结果表明，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39.51%和15.9%，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，结晶行为显示HDPE/CSW复合材料为二维片晶生长。原始HDPE的热降解反应活化能为244.11 kJ/mol，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。

Abstract:

HDPE/CSW composites were prepared by melt blending method using γ-methacryloxypropyltrimethoxysilane (KH570) modified calcium sulphate whiskers (CSW) as filler for high density polyethylene (HDPE). The effects of KH570-modified CSW on the properties of the composite HDPE/CSW were characterized by SEM, XRD, TG and DSC. The results showed that the tensile and flexural strengths of HDPE/CSW increased by 39.51% and 15.9%, respectively, compared with pure HDPE at a CSW mass fraction of 20%, and were prone to heterogeneous crystallization, which enhanced the heat resistance and crystallinity of the HDPE/CSW composites, and the crystallization behaviour showed that the HDPE/CSW composites grew as two-dimensional sheet crystals. The activation energy of thermal degradation reaction of the original HDPE was 244.11 kJ/mol, and the activation energy of thermal degradation reaction of HDPE/CSW composites decreased to 236.99 kJ/mol at 50% mass fraction of CSW, indicating that CSW enhanced the thermal degradation reaction rate of HDPE/CSW composites and extended the use range of the composites.