LLDPE/LDPE/TiO2复合膜的分散及光学性能

讨论了纳米TiO2在线型低密度聚乙烯（LLDPE），低密度聚乙烯（LDPE）复合体系中的分散和体系流变行为，研究了复合薄膜的光学性能。结果表明，以高流动性LDPE为基体的纳米TiO2母料，加入LLDPE，LDPE体系中后。复合体系的表观粘度有所提高。但拉伸粘度显著下降。纳米TiO2母料在LLDPE／LDPE复合体系中具有良好的分散性，复合薄膜中的纳米TiO2为一次粒子。纳米TiO2起到了异相成核剂的作用。球晶的粒子得到细化。在本研究的纳米填充范围内（质量分数不大于1.0％），复合薄膜的透光度基本不变。雾度发生了较大幅度上升，复合薄膜在紫外光区域的吸收显著增强。

DISPERSION AND OPTICAL BEHAVIOR OF LLDPE/LDPE/NANO-TiO2 COMPOSITE FILMS

The rheology of composites and the dispersion of nano-TiO2 in LLDPE/LDPE composites were studied. Optical behavior of composite films was researched. The results show that LDPE/nano- TiO2 matrix prepared by high flow LDPE has well fluidity. The apparent viscosity of I.LDPE/ LDPE/nano-TiO2 is higher than that of LLDPE/LDPE. However, its extension viscosity is lower than that of LLDPE/LDPE obviously. LDPE/nano-TiO2, matrix has a well dispersion in LLDPE/ LDPE composites, and nano-TiO2 particles in composite films are primary particle with nano scale. Moreover, nano-TiO2 exhibites an apparent inducing nucleation effect on the crystallization of polyethylene. The size of the crystal decreases with the introduction of TiO2. When the content of nano- TiO2 in composites is less than or equal to 1.0%, the visible light transmittance almost keeps unchangeable, the haze decreases drastically, and LI.DPE/LDPE/nano-TiO2 composites film has a strong absorption ability in ultraviolet area.