丙烯酸-丙烯酸钠共聚物在水溶液中的离解

聚丙烯酸和聚丙烯酸盐是一类重要的水溶性聚合物，也是典型的聚电解质的代表．聚电解质在溶液中可以离解为聚离子和对离子，这一行为是它的根本特性．聚电解质的离解行为与相应的小分子．弱酸和弱酸强碱所生成的盐的离解行为有很大的不同，从而引发了许多实验和理论的研究.早期的工作，大都是用电位滴定的方法研究酸性聚电解质的离解，

DISSOCIATION OF ACRYLIC ACID-SODIUM ACRYLATE COPOLYMERS IN AQUEOUS SOLUTIONS

In order to investigate the property and concentration dependence of dissociation and hydrolysis of polyelectrolytes,acrylic acid-sodium acrylate copolymers with various degree of neutralization were prepared by adding calculated amounts of sodium hydroxide into the aqueous solutions of a poly(acrylic acid) sample,and the pH values of the solutions covering a wide concentration range were measured for each copolymer at 25℃.It was found that the pH values of the solutions of a copolymer with degree of neutralization of 0.96 kept constant and equaled to 9.80 as c>0.001 mol/L.For another copolymer with degree of neutralization of 0.30,the pH values of its solutions remained constant and equaled to 6.25 as c<0.001 mol/L.These two copolymers may serve as polymeric buffer reagents which couldn't penetrate through semi-permeable membranes in the corresponding concentration regions.