水溶性超高分子量聚丙烯酰胺的辐射反相乳液合成

RADIATION POLYMERIZATION OF ACRYLAMIDE WITH SUPER-HIGH MOLECULAR WEIGHT IN INVERSE EMULSION

用^(60)Coγ射线引发丙烯酰胺反相乳液聚合，研究了吸收剂量、剂量率、乳化剂含量和单体含量及辐射后效应对聚丙烯酰胺分子量的影响，特别是采用高剂量率引发，特低剂量率辐射聚合的手段，不仅提高了产物分子量，缩短聚合时间，而且提高了转化率，防止了聚合物的交联。

The inverse emulsion polyrnerization of acrylamide has been studied with γ-ray initiation. Polyacrylamide with super high molecular weight over ten million(11 × 10~6), which is very important in application as flocculant, is obtained. In this work, some mothods are taken to enhance the molecular weight as follows: (1)In order to prepare soluble polyacrylamide with super high molecular weight, the better conditions are: the emulsifier content is about 2% and the monomer concentration is about 20%~24% in the composition of monomer emulsion, and the absorbed dose is about 500-600 Gy. (2)Initiating with high dose rate and polymerizing with low dose rate can not only enhance the molecular weight of product, but also curtail the polymerizing time. (3)Stopping radiation when the conversion gets to about 10% and post-polymerizing outside the radiation source until the conversion gets to 82% can obtain polyacrylamide with super high molecular weight, and shorten the irradiation time as well.