偏氯乙烯/丙烯腈悬浮共聚速率模型

RATE MODEL OF VINYLIDENE CHLORIDE/ACRYLONITRILE SUSPENSION COPOLYMERIZATION

以Ｗｅｓｓｌｉｎｇ 偏氯乙烯均聚速率模型为基础，提出了偏氯乙烯／丙烯腈悬浮共聚新的速率模型ｄｘ／ｄｔ＝ ｋｘｍ［Ｉ］ｎ０ ｅｘｐ （－ ｎｋｄｔ），式中ｋ、ｍ 、ｎ 是模型参数。通过研究单体组成、聚合温度、引发剂浓度等对共聚速率的影响，发现在５５～７５ ℃之间，ｍ 和ｎ 分别是值为０．１４３ 和０．５ 的常数，而ｋ 随温度变化且符合Ａｒｒｈｅｎｉｕｓ关系式，其表观活化能为８７．０ ｋＪ／ｍ ｏｌ。在转化率低于８５％ 时，模型的计算值能较好地与实验测定值相吻合。

Based on Wessling model for vinylidene chloride(VDC) homopolymerization,a new kinetic model, which is d x /d t = kx m[I] n 0 exp (- nk d t ) where k,m and n are the model parameters, is proposed for 69∶31(mol) VDC/acrylonitrile(AN) suspension copolymerization. After studying on the factors which affect on copolymerization rate such as feeding ratio of comonomers, temperature( T ) and initator concentration, it is found that the values of m and n are almost constant with temperature from 55 ℃ to 75 ℃, which are 0.143 and 0.5 respectively. The variation of k with T is consistent with Arrhenius expression and the apparent active energy is 87.0 kJ/mol. The value calculated by our model is consistent well with experiment at conversion lower than 85%.