HCBR/LCBR共混体系对HIPS结构与性能的影响

Effect of HCBR/LCBR blends on structure and properties of high impact polystyrene

采用动态热力学分析仪、激光粒径分析仪和凝胶渗透色谱仪等分析了高顺式聚丁二烯橡胶/低顺式聚丁二烯橡胶(LCBR)共混体系对高抗冲聚苯乙烯(HIPS)结构和性能的影响。结果表明:随LCBR用量增加,HIPS的结构和性能发生变化。交联度增加,橡胶相粒径减小,聚苯乙烯相的相对分子质量不变,而凝胶含量在w(LCBR)为20%时出现最大值;HIPS的拉伸强度基本不变,熔体流动速率、冲击强度、光泽度降低,维卡软化温度增加;受多重因素影响,HIPS的弯曲模量、断裂拉伸应变及负荷变形温度的变化较为复杂。

The influences of high cis-l,4-polybutadiene rubber（HCBR）/low cis-l,4-polybutadiene rubber（LCBR） blends on structure and properties of high impact polystyrene（HIPS） were analyzed by means of dynamic mechanical analyzer（DMA）,laser particle size analyzer and gel permeation chromatography（GPC）. The results indicated that the structure and properties of HIPS varied with the augmentation of LCBR dosage. The structural aspects showed the degree of crosslinking increased, particle size of rubber phase decreased and the relative molecular mass of polystyrene phase remained unchanged. The gel content reached maximum when the mass fraction of LCBR was 20%. The performance aspects showed that the tensile strength was steady, melt flow rate, impact strength and gloss decreased, but Vicat softening temperature increased, and the variations of flexu- ral modulus, tensile strain at break and thermal deformation temperature that were affected by multiple factors were complicated.