PB-g-PS水泥改性剂的合成与表征

采用半连续种子乳液接枝聚合枝术,在聚丁二烯乳胶粒子上接枝共聚苯乙烯,合成了聚丁二烯接枝聚苯乙烯(PB-g-PS)接枝共聚物。研究了合成工艺条件对接枝共聚反应的影响,实验结果表明,苯乙烯在聚丁二烯橡胶粒子上的接枝效率和接枝度随聚丁二烯对苯乙烯质量比的增加而降低,随反应温度的增加而增加,随引发剂浓度的增加呈先增加后降低的变化趋势,接枝效率随单体滴加时间的增加而增加,接枝度则呈先增加后降低的变化趋势。利用FTIR和1H-NMR对PB-g-PS接枝共聚物进行了表征,证明合成了目的产物。利用TEM对PB-g-PS乳胶粒子进行了形态观察,接枝物为球形粒子,且具有核壳结构。

Synthesis and characterization of PB-g-PS cement modified agent

Graft copolymers of styrene（St） onto polybutadiene（PB） were prepared via semicontinuous seeded emulsion grafting copolymerization method using a redox initiator system.The effect of initiator,reaction temperature,qualitys ratio of PB/PS,and monomer dropping time on the graft copolymerization were investigated.The results showed that the grafting efficiency（GE） and degree of grafting（DG） were increased with increasing reaction temperature and decreas mass ratio of PB/PS.The GE and DG were first increased with increasing initiator content for low content,and then begin to decrease of higher content of initiator.The GE was increased with increasing monomer dropping time.The DG was increased first,and then decreaseing with increasing monomer dropping time.The synthesized PB-g-PS was confirmed by FTIR and 1H-NMR.The morphology of PB-g-PS latex particle were studied by TEM.The study showed that PB-g-PS latex particle is ball-like,and has a core-shell shaped structure.