【摘要】 以二羟基二过碘酸合镍(Ⅳ)钾为氧化剂,具有还原性端羟基基团的聚己二酸1,2-丙二醇酯(PPA)为还原剂,组成氧化还原引发体系,于碱性介质中引发PPA与丙烯酸甲酯(MA)的自由基嵌段共聚合反应。考察了引发剂浓度、MA与PPA的质量比、反应温度和时间对嵌段参数的影响。在引发剂浓度为4·972×10-5mol/L、单体MA与底物PPA的质量比3·93∶1、反应温度30℃、反应时间60min的优化条件下,制得高嵌段参数的共聚物。计算出该反应的活化能约为35·65kJ/mol。利用红外光谱、氢核磁共振对嵌段共聚物进行了表征,并探讨了引发机理。更多还原

【Abstract】 Free radical block copolymerization of methyl acrylate(MA) with poly (1,2-propylene glycol adipate)(PPA) using potassium diperiodatonickelate(Ⅳ)(DPN) as initiator was carried out in alkaline medium.The effects of initiator concentration,mass ratio of MA to PPA,reaction temperature,and reaction time on the parameters of the block copolymerization were examined.The block copolymer with high block percentage was obtained under initiator concentration 4.972×10~ -5 mol/L ,mass ratio of MA to PPA 3.93∶1 ,reaction temperature 30 ℃ ,and reaction time 60 min.The overall activation energy of this block copolymerization was about 35.65 kJ/mol .The block copolymer was characterized by IR and ~1HNMR.The initiation mechanism of the block copolymerization was discussed.更多还原