甲基丙烯酸甲酯-丁二烯-苯乙烯树脂的合成及其对聚氯乙烯的改性

采用种子乳液接枝聚合技术合成了甲基丙烯酸甲酯(MMA)-丁二烯-苯乙烯树脂(MBS),考察了复合乳化剂浓度、CO2用量对丁苯胶乳粒径及其分布、胶乳稳定性的影响;研究了接枝单体滴加方式和接枝聚合反应温度对MBS体系稳定性和接枝效率的影响;讨论了MBS改性聚氯乙烯(PVC)的影响因素;提出了丁苯胶乳的碳酸化扩径附聚法和MBS胶乳的SO2凝聚新工艺。结果表明:在丁二烯/苯乙烯(质量比)为90/10、阴离子/非离子复合乳化剂浓度为35~40g/L、丁苯胶乳采用CO2附聚扩径、部分MMA预溶胀和其余MMA连续滴加的方式以及MBS胶乳SO2凝聚新工艺的条件下,所得MBS树脂粉料颗粒均匀,40~180目的颗粒质量分数达96%,堆积密度在0.4g/cm3以上;PVC/MBS(质量比为100/8)共混物的冲击强度达22.6kJ/m2。

Synthesis of methyl methacrylate-butadiene-styrene resin and its modification to poly (vinyl chloride)

Methyl methacrylate(MMA)-butadiene-styrene(MBS) resin was synthesized via seeding grafting emulsion polymerization technique. The effects of the concentration of complex emulsifier and the amounts of CO2 on particle size, distribution and stability of butadine-styrene latex were investigated. The adding type of MMA and the polymerization temperature on stability and grafting efficiency of MBS latex were studied. The influence fectors of MBS modified poly(vinyl chloride)(PVC) were discussed. Moreover, new methods for agglomerating butadiene-styrene latex particles via carbonation and coagulating MBS latex by SO2 were proposed. The results showed that the MBS in which the mass fraction of powder was 96% at 40~180 mesh, and bulk density was above 0.4 g/cm3 was prepared when the mass ratio of butadiene/styrene was 90/10, the concentration of complex emulsifier was 35~40 g/L, carbonation enlarged the particle size of butadiene-styrene latex, part MMA was pre-swollen and others added continuously as well as SO2 was used. The impact strength of PVC/MBS(mass ratio was 100/8) was 22.6 kJ/m2.