丙烯腈与N-乙烯基吡咯烷酮共聚体系对单体竞聚率的影响

利用Kelen—Tudos方法测算丙烯腈(AN)与N—乙烯基吡咯烷酮(NVP)自由基共聚合单体竞聚率，研究了不同反应体系对单体竞聚率的影响。结果发现：在水相悬浮聚合体系中，转化率小于18％时，两单体的竞聚率同DMS0均相溶液聚合结果相近；转化率较大时，同容液聚合结果偏差较大。H2O／DMS0混合溶剂悬浮聚合时，当水含量超过60％(质量比)后，单体竞聚率向水相悬浮聚合结果靠近。溶剂的极性增大，rAN与rNVP值均减小。随反应温度升高，共聚反应向理想共聚方向进行。

EFFECT OF ACRYLONITRILE-N-VINYLPYRROLIDONE COPOLYMERIZATION SYSTEMS ON MONOMER REACTIVITY RATIOS

Effect of different acrylonitrile N vinylpyrrolidone free radical copolymerization systems on reactivity ratios for monomers has been studied. The valoues of reactivity ratios were calculated by the method of Kelen Tudos. It shows that reactivity ratios in aqueous suspension polymerization system are similar to those in solution polymerization system when the conversion is less than 18%. As the conversion increases, the results are very different. H 2O/DMSO mixture solvent was also used for producing the AN NVP copolymer. In water rich reaction medium( m H 2O / m DMSO =60/40), reactivity ratios are equivalent to those in aqueous suspension polymerization system. With an increase of polarity of solvent, both r AN and r NVP reduce. When the reaction temperature rises, reaction gradually changs to ideal copolymerization.