摘要
将海藻酸钠(SA)与CuCl_2·2H_2O反应得到一种配位聚合物海藻酸铜(Cu-An).以ESR、电导率、IR和XPS方法对此配位聚合物进行表征,确定了组成与结构;同时研究了甲基丙烯酸甲酯(MMA)在该配位聚合物膜、HSO_3^-和水体系催化引发作用下的聚合反应历程.结果表明,配位聚合物的中心离子Cu^(2+)与两个海藻酸(An)链节单元上的两个羧羟基氧原子和两个离解氢原子的羧羟基氧原子以共价型配位,配位数为4.MMA在上述的催化引发体系中是按照自由基加聚反应历程进行聚合的,PMMA呈无规结构.Cu-An在催化引发体系中起着催化剂的配位催化作用.
The film of copper alginate coordinated polymer was obtained by stirring sodium alginate film in a 15% CuCl2·2H2O solution. The copper alginate film was characterized by ESR spectroscopy, specific conductivity, IR spectrometry and XPS. Its composition and surface structure were determined. The catalytic property of copper alginate for polymerization of MMA was studied. The reaction mechanism of MMA polymerization in copper alginate and HSOf solution system is discussed. Experimental results show that the copper ion of copper alginate is coordinated with two carboxyl hydroxyl oxygen atoms and two deprotonic carboxyl hydroxyl oxygen atoms of two alginate units by covalent bond, the coordination number is four. The copper alginate is shown to be active at pH = 7 for catalyzing the polymerization. The copper alginate serves as catalyst in coordination catalysis. MMA polymerized by free radical addition polymerization and the PMMA obtained possessed random structure.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2000年第4期407-413,共7页
Acta Chimica Sinica
基金
福建省教委资助课题
关键词
海藻酸
配位聚合物
海藻酸铜
MMA
自由基聚合
alginate, coordinated polymer, copper alginate, coordination catalysis, MMA, free radical polymerization
