LLDPE/纳米SiO_2复合材料的力学性能和光学性能研究

采用熔融共混方法制备了LLDPE 纳米SiO2 复合材料 ,并对该体系的力学性能和光学性能进行了系统研究 .结果表明 ,随着纳米SiO2 的加入 ,复合材料的弹性模量显著提高 ,冲击强度与拉伸强度呈峰形变化 ,且均在SiO2 含量为 3phr左右达到最大值 .加入少量的纳米SiO2 后 ,复合材料薄膜对长波红外线 (7～ 1 1 μm)的吸收能力较LLDPE膜有了显著提高 ,透光率略有下降但雾度提高 ,透光质量得到改善 .同时表明 ,纳米SiO2 的表面处理方法对膜的光学性能有显著影响

MECHANICAL AND OPTICAL PROPERTIES OF LLDPE/NANO-SiO2 COMPOSITES

LLDPE/nano-SiO 2 composites were prepared by melt-blending, and the mechanical and optical properties of the composites were investigated.The results showed that the elastic modulus of the composites obviously increased with the increase of SiO 2 content, and the breaking elongation remained unchanged at low content of SiO 2.Both the impact strength and the tensile strength of composites were improved with an increase of nano-SiO 2 content and reached maximum when 3?phr nano-SiO 2 were introduced.The IR absorptivity (ranging from 7?μm to 11?μm) of the composite films increased dramatically with a small amount of nano-SiO 2 introduced.Although the visible light transmittance of the film declined a little compared with the pure LLDPE,the haze value increased much.It was also found that the surface-treatment method of nano-SiO 2 has great influence on the optical properties of the composite films.The infrared absorptivity and haze of the composites filled with nano-SiO 2 treated by silane coupling agent in ethanol were superior to those of the composites filled with nano-SiO 2 treated by silane coupling agent in a ball mill,because the former has smaller particle size and more uniform dispersion in matrix than the latter.