铜络合物催化体系下丙烯酸-丙烯酰胺的可控聚合

实验利用反向原子转移自由基聚合,在均相水介质中,以铜(Ⅱ)催化体系,水溶性引发剂引发丙烯酰胺/丙烯酸的可控聚合。以过硫酸钾(KPS)为引发剂,以氯化铜(CuCl_2)与乙二胺(en)形成的络合物为催化剂,在水相中进行丙烯酸(AA)和丙烯酰胺(AM)可控自由基聚合反应。对丙烯酰胺与丙烯酸共聚反应可控性进行了讨论。聚合反应的最佳条件为:45℃下原料配比为n(AM):n(CuCl_2):n(en):n(KPS)=400:0.7:1.4:0.25。在此条件下,聚合反应的线性相关系数良好,单体转化率达96.63%,黏均相对分子质量达1.11×10~7。

CONTROLLED POLYMERIZATION OF AA/AM CATALYZEDBY COPPER COMPLEX CATALYST

The Reverse atom transfer radical polymerization(RATRR) of acrylamide (AM) and acrylic acid (AA) was studied using potassium peroxydisulfate(KPS) as the water-soluble initiator,Cu(Ⅱ) complex as catalyst,in homogeneous aqueous medium under very low temperature 35-50℃.KPS was used as initiator,CuCl_2 complexed by ethylenediamine (en) was used as catalyst to synthesize polyacrylamide in water medium using the measure of RATRP.The controllable reaction was achieved through controlling ratio of materials,polymerization temperature,CuCl_2 and en ratio and other conditions. The evolution of molecular weight vs conversion was studied to discuss the controllability of amide polymerization.The results showed that when the materials ratios n(AM):n (CuCl_2): n(en):n(KPS)= 400:0.7:1.4:0.25,45℃,the polymerization reaction could be controlled.