摘要
研究了乙烯-1-丁烯共聚物(PEB)与苯乙烯-丙烯腈(St-AN)悬浮接枝共聚体系的反应行为随反应时间的延长而变化的规律。核磁共振氢谱(1 H-NMR)分析表明反应产物由未接枝PEB、接枝共聚物PEB-g-SAN和非接枝共聚物SAN构成,无交联产物存在。体系在反应的最初阶段接枝共聚反应速率高于非接枝共聚反应速率。凝胶渗透色谱(GPC)分析表明,在整个反应过程中发生了未接枝PEB和PEB-g-SAN主链的降解反应。共聚反应在反应时间为240min时结束,此后发生少量未接枝PEB和PEB-g-SAN结合的反应,导致产物的橡胶接枝率逐渐提高、产物与SAN树脂共混物的缺口冲击强度逐渐上升、以及用SEM分析证实的共混物增韧机理由空穴化的脆性断裂向高度剪切屈服的韧性断裂转变。
The effects of reaction time on reaction behavior of suspension grafting copolymerization of styrene（St） and acrylonitrile（AN） from poly（ethene-co-1-butene）（PEB） were investigated.1H nuclear magnetic resonance（1H-NMR） showed that the grafted copolymer products contain non-grafted PEB,copolymer PEB-g-SAN and non-graft graft copolymer SAN,without cross-linked polymer（CP）.In the early stage of reaction the rate of the grafted copolymerization was faster than that of the non-graft copolymerization.Gel permeation chromatography（GPC） analysis revealed the degradation reactions of PEB and PEB-g-SAN happened in the whole reaction process.It was found that the mainly graft reaction and the non-graft copolymerization were finished before the first 240 minutes of the reaction.After this time there was few non-graft PEB bonded with PEB-g-SAN,which brings about the increasing gradually of rubber grafting ratio,the notched impact strength of AEBS and the toughening mechanism of AEBS transformed from brittle fracture with cavitations to severe shear yielding,as analyzed by SEM.
出处
《弹性体》
CAS
2013年第3期1-8,共8页
China Elastomerics
基金
广州市科技计划重点项目(2007Z2-D0161)
关键词
乙烯-1-丁烯共聚物
苯乙烯-丙烯腈
接枝共聚
相对分子质量及其分布
反应机理
共混物
增韧机理
poly（ethene-co-1-butene）
styrene（St）-acrylonitrile（AN）
grafting copolymerization
relative molecular weight and its distribution
reaction mechanism
blends
toughening mechanism
