GA-g-P AA/ST复合水凝胶的合成与表征

Synthesis and Characterization of GA-g-P AA / ST Composite Hydro-gels

摘要:

以阿拉伯胶（GA）、丙烯酸（AA）、海泡石黏土（ST）为原料，采用微波辐射法，通过接枝共聚合成了GA-g-P AA / ST复合水凝胶，利用FTIR、XRD和SEM表征了凝胶的结构和形貌，用TG分析了凝胶的热稳定性能，同时探讨了凝胶在不同价态阳离子盐溶液的溶胀行为和保水性能。结果显示：GA、ST和AA发生了接枝共聚反应，共聚物插层进入到ST的层间，形成剥离型均匀的三维网络复合高吸水凝胶。当盐溶液浓度为20 mmol /L时，凝胶在 NaCl、BaCl2、FeCl3 溶液中的吸水倍率分别为 112、38和29g/g。活性剂溶液浓度为20 mmol /L时，凝胶在十二烷基硫酸钠( SDS) 和十六烷基三甲基溴化铵( CTAB) 溶液的吸水倍率分别为135和105g /g。凝胶在NaCl和BaCl2盐溶液循环三次后吸水倍率为80和12g /g，表明凝胶在NaCl和BaCl2盐溶液具有较强的盐响应性能和良好的可逆行为，凝胶具有较好的热稳定性和保水性能。

Abstract:

GA-g-PAA/ST composite hydrogels were prepared by graft copolymerization of gum arabic (GA),acrylic acid (AA),sepiolite clay (ST) under microwave irradiation.The structure and morphology of GA-g-PAA/ST composite hydrogels were characterized by FTIR XRD and SEM.The thermal stability of the hydrogel was analyzed by TG.The swelling behavior and water retention of the hydrogel in different cationic salt solutions were also discussed.The results showed that the graft copolymerization reaction took place between the two groups,and the copolymer intercalated into the interlayer of ST to form a delaminated three-dimensional network composite hydrogel.When the concentration of salt is 20mmol/L,the absorbency of the hydrogel in NaCl、BaCl2、AlCl3 solution is 112、38 and 29g/g,respectively.When the concentration of surfactant solution was 20mmol/L,the absorbency of the hydrogel in SDS solution and CTAB solution was 135 and 105g/g,repectively.After three cycles of NaCl and BaCl2 salt solution,the water absorption ratio of the hydrogel is 80 and 12g/g,indicating that the hydrogel has strong salt responsive property and good reversible behavior in NaCl and BaCl2 salt solution.The hydrogel has good thermal stability and water retetion.