溶液自由基法高分子量聚丙烯腈的合成

Solution Radical Controlled Polymerization of High Average Molecular Weight Polyacrylonitrile

采用以偶氮二异丁腈(AIBN)为引发剂,丙烯腈(AN)与丙烯酰胺(AM)在二甲亚砜(DMSO)溶剂中的自由基溶液共聚合,考察了单体浓度,单体配比,引发剂含量,反应温度和聚合时间等对共聚反应的影响。分别用称量法和乌氏黏度计测定了反应的转化率和聚合物的相对分子质量,用红外光谱对聚合物的结构进行了分析。研究结果表明,提高反应温度及引发剂含量,则转化率升高,分子量下降。单体浓度越高,分子量及转化率均可提高。这符合自由基聚合的一般规律。通过工艺优化,共聚物的转化率可达90%以上,黏均分子量约21万。

Free-radical solution copolymerization of acrylamide（AM） and acrylonitrile（AN） was carried out in dimethyl sulfoxide（DMSO） using azodiisobutyronitrile（AIBN） as initiator. The effect of monomer concentration,ratio of monomer,initiator content,reaction temperature and polymerization time on copolymerization was studied. The conversion rate of the polymerization and the relative molecular weight of the product were determined by weight method and Ubbelodhe viscosimeter. IR was used to characterize the structures of the polymers. The results show that the conversion of copolymerization increases and the molecular weight decreases as reaction temperature increases and initiator content increases. The conversion of copolymerization increases and the molecular weight increases as monomer concentration increases. the copolymerization is in accordance with the free radical copolymerization. By optimization of polymerization conditions,polyacrylonitrile of molecular weight at approximately 2.1×105 and conversion at 90% can be obtained.