聚丙烯酸类超强吸水剂的合成与性能研究

以丙烯酸烯丙酯作为交联剂、丙烯酸(AA)为单体、过硫酸钾(KPS)为引发剂,采用溶液聚合法合成了一种聚丙烯酸类超强吸水剂。研究了合成条件对吸水性能的影响:当ρ(丙烯酸烯丙酯)=0 594g/L,ρ(KPS)=0 178g/L,单体中和度x(丙烯酸钠)=90%,c(丙烯酸钠)=4 17mol/L,聚合温度为60℃时,制得的聚合物每克吸去离子水最高达到1360mL,吸盐水(生理盐水)162mL。所得的聚合物具有良好的吸水可逆性,30min的吸水量可以达到饱和吸水量的90%。制得聚合物的热重分析表明,未吸水的该聚合物在350℃开始分解。聚合物吸水前后XRD测试结果显示:吸水前聚合物结构基本无规整性,吸水后膨胀使主链展开,结构趋于规整。

Synthesis and Characterization of Super Absorbent by Polymerization of Sodium Acrylate

A super absorbent of poly(sodium acrylate) was prepared by solution polymerisation with allyl acrylate as crosslinking agent,acrylic acid as monomer and potassium persulphate(KPS) as initiator.Parameters affecting the absorbability of the polymer were studied.When ρ(crosslinker)=0.594 g/L,ρ(KPS)=0.178 g/L,neutralization degree of monomer x(sodium acrylate)=90%,c(sodium acrylate)=4.17 mol/L,and polymerization temperature was 60 ℃,the absorbability of the polymer is up to 1360 mL/g and 162 mL/g in case of deionising water and w(NaCl)=0.9% water solution,respectively.The obtained polymer has good water absorption reversibility and the water absorbency can reach 90% of the maximum absorbability after 30 min.TGA showed the dried sample had an initial decomposition temperature of 350 ℃.XRD spectrum showed that structure of the polymer without water is orderless and when the polymer absorbed water,(it′s) main chain is spread and the structure inclines to orderliness.