接枝改性SBS对PS/SBS/CaCO_3复合材料形态和力学性能的影响

采用马来酸酐(MAH)和苯乙烯(St)作为接枝单体,通过溶液聚合法合成接枝极性基团的苯乙烯-丁二烯-苯乙烯三嵌段共聚物(SBS),然后与聚苯乙烯(PS)基体、碳酸钙(CaCO_3)粒子复合,用傅立叶红外光谱仪表征接枝处理前后SBS表面化学结构的变化;并研究了SBS改性对复合材料微观结构和力学性能的影响.结果表明:双单体溶液聚合法成功地将极性基团接枝在SBS链上;填充SBS-g-MAH后,促进CaCO_3在PS基体中的分散、改善PS-CaCO_3粒子间界面粘接,起到良好的增容作用;SBS-g-MAH和CaCO_3粒子对PS基体具有协同增强增韧作用,同时能提高复合材料的拉伸强度和冲击强度.

Effect of Grafting Modification of SBS on Morphology and Mechanical Properties of PS/SBS/CaCO_3 Ternary Composites

The styrene-butadiene-styrene triblock copolymer was modified by solution grafting eopolymerization with maleic anhydride(MAH) and styrene(St), then compounded with PS and CaCO_3. The effect of grafting modification of SBS on morphology and mechanical properties of PS/SBS-g-MAH/CaCO_3 ternary eomposites were investigated. The FT-IR spectra confirmed that the MAH molecules were grafted on the SBS segmented. The modification of SBS enhanced the compatibility between CaCO_3 and PS, improved the dispersion of CaCO_3 particles in PS matrix, and enhanced the interfacial adhesion between CaCO_3 and matrix. Thereby, the tensile strength and notch impact strength of PS/SBS-g-MAH/CaCO_3 ternary composites were improved at the same time.