采用乳液接枝聚合技术在粒径300nm 的聚丁二烯(PB)乳胶粒子上接枝苯乙烯(St),制备了核壳比(PB与PS的质量比)为70/30的PB-g-PS接枝共聚物。将其与高抗冲聚苯乙烯(HIPS)、聚苯醚(PPO)和聚苯乙烯(PS)树脂进行熔融共混制得了一系列HIPS/PPO/PS/PB-g-PS共混物,研究了PPO/PS的组成对共混物力学性能和形态结构的影响。结果发现,在HIPS/PPO/PS共混体系中引入PB-g-PS后,HIPS中的大粒径橡胶粒子(2μm~4μm)和PB-g-PS小粒径橡胶粒子(300nm)具有良好的协同增韧作用;随着基体中PPO 含量的增加,共混物的冲击强度、拉伸强度和断裂伸长率均呈上升趋势;当PPO/PS质量比在25/75~50/50范围内3时,共混物冲击强度出现突变式增大,由300J/m 提高至600J/m。形态结构研究结果表明,随着基体中PPO 含量增加,PB-g-PS弹性体粒子在基体中的分散程度获得明显改善;当PPO 质量分数低于10%时,主要为银纹屈服形变;当PPO 质量分数高于20%时,主要为剪切屈服形变。
PB-g-PS graft copolymer with core/shell（PB/PS） ratio of 70/30, was prepared by grafting styrene onto polybutadiene(PB) latex with diameter of 300 nm through emulsion polymerization technique. By melt blending the graft copolymer with high impact polystyrene (HIPS), polyphenylene oxide(PPO) and polystyrene(PS), a series of HIPS/PPO/PS/ PB-g-PS blends were obtained, and the effects of PPO/PS ratios on the mechanical properties and morphology of the blends were investigated. It is found that there is a good synergism toughening behaviour between large rubber particles(2 μm～4 μm) in HIPS resin and PB-g-PS small rubber particle with a size of 300 nm by adding PB-g-PS graft polymer in HIPS/PPO/PS blends. The impact strength, tensile strength and strain at break of the blends are enhanced with increasing the amount of PPO in matrix; the impact strength of the blends appears a big margin improvement with the value from 300 J/m to 600 J/m when PPO/PS mass ratio is from 25/75 to 50/50. The morphology results show that the dispersion of PB-g-PS impact modifier in matrix is greatly improved with increasing the amount of PPO. Craze is the main deformation mechanism when the mass fraction of PPO is less than 10%, and shear yield is the main deformation mechanism when it is more than 20%.
陈英楠,宋立新,刘明明,任 亮,张明耀,张会轩. HIPS/PPO/PS/PB-g-PS共混物的力学性能与形态结构[J].高分子材料科学与工程,2014,30(3):68-71.复制