POE和SEBS对PP韧性以及光学性能的影响

Effects of POE and SEBS on Toughness and Optical Properties of PP

采用双螺杆挤出机,选用SEBS及3种型号的POE,通过熔融共混的办法改性PP,对比了POE及SEBS对PP力学性能、微观结构、光学性能、结晶性能的影响。力学性能分析发现,POE以及SEBS对PP均有增韧作用,但POE的增韧效果优于SEBS。SEM分析发现,POE以颗粒状的形式分散在基体中,可以看到明显的海岛结构,而加入SEBS则看不到明显的海岛结构,呈均相体系。透光率和雾度测试发现,PP/POE体系的透明度下降,雾度升高,而与此不同的是,PP/SEBS体系的透明度先升高后下降,雾度先下降后升高。偏光显微镜测试分析发现,加入POE之后,球晶不完整,尺寸变小,而加入SEBS之后,球晶尺寸变得更小,且结晶规整。DSC分析发现,加入POE以及SEBS之后,体系的结晶度均下将,但是POE的部分结晶降低了PP的透明性。

SEBS and three kinds of POE were selected to melt blending with pp by using twin screw extruder. The effects of POE and SEBS on mechanical properties, microstructure, optical properties and crystalline properties of PP were compared. It was found that POE had better toughening effects on PP than SEBS. The SEM analysis showed that POE dispersed in granular morphology and the island structure could be found obviously, while the addition of SEBS could not. After POE was added, the transparency of the material showed a slight downward trend, while the haze increased gradually. After the SEBS was added, the transparency increased first and then decreased, haze decreased first and then increased. The polarizing microscope showed that the crystallizations were incomplete and the size of the spherocrystals turned smaller after adding POE. With the addition of SEBS, the size of the spherocrystals turned smaller and the crystal structures were regular. DSC analysis showed that, after the POE and SEBS were added, the crystallinity of the two systems decreased. In POE system, the transparency of PP was reduced because of the partial crystallization of POE.