热拉伸对PET/LLDPE薄膜光学性能的影响  

The Influences of Hot Stretch on Optical Properties of PET / LLDPE Film

作　　者：刘建[1] 马寒冰[1] 邓银洁 陈燕燕[1] 王晓梅[1] 

机构地区：[1]西南科技大学四川省非金属复合与功能材料重点实验室-省部共建国家重点实验室培育基地,四川绵阳621010

出　　处：《西南科技大学学报》2015年第1期7-11,共5页Journal of Southwest University of Science and Technology

基　　金：国家863计划项目(2012AA050304);西南科技大学研究生创新基金(14ycxjj0024)

摘　　要：将聚对苯二甲酸乙二醇酯(PET)与线性低密度聚乙烯(LLDPE)熔融共混,然后流延成膜,并通过热拉伸成不同厚度的薄膜,讨论了薄膜厚度和热拉伸方式对薄膜透光率和雾度的影响。用扫描电子显微镜(SEM)对掺入不同含量的LLDPE薄膜断面进行了形态研究,结果表明在薄膜厚度相同的情况下,热拉伸可以提高薄膜的透光率,降低雾度。扫描电子显微镜(SEM)观察到在PET/LLDPE薄膜中,LLDPE作为分散相随机分布在PET基体中,且随着拉伸倍数的增加,分散相颗粒逐渐由球状被拉伸为椭球状;随着分散相颗粒长短轴比增加,入射光垂直于长轴入射几率增大,透过颗粒的光线随之增多,引起透光率上升,但是由于散射光更集中在入射光方向的正前向,散射减弱,雾度下降。To prepare the PET/LLDPE films in different thicknesses, the PET was first mixed with LL- DPE, and then the PET/LLDPE composite was melt, extruded, slobbered, and hot stretched. Morpholo- gy of films was analyzed by SEM and the effect of film thickness and methods of hot - stretching on the transmittance and haze was also discussed. The results show that hot stretching could increase the trans- mittance and decrease the haze of the films in the same thickness. The particles of LLDPE are distributed in PET matrix randomly, and the shape of disperse phase is changed from sphere to ellipsoid when the hot -stretching ratio increases. With the long and short axial ratios of disperse phase particles increasing, the probability of the incident light perpendicular to the long axis increases and the light rays transmits through particles also increase, both of which lead to an increase of transmittance. But the scattering light weakens and the haze decreases because the scattering light is focused intensely on the forward direction of incident light.

关 键 词：PET/LLDPE薄膜 热拉伸 拉伸倍数 分散相形态 光学性能 

分 类 号：TB332[一般工业技术—材料科学与工程]