微波辐射合成聚丙烯酸钠/膨润土复合高吸水树脂结构及性能研究

以膨润土(BT)和丙烯酸(AA)为原料，在微波辐射下合成PAA Na/BT复合高吸水树脂，采用单因素实验法优化并确定了最高吸水倍率的合成条件，并采用红外光谱(FTIR)、X射线衍射(XRD)、扫描电子显微镜(SEM)对产物结构及表面形貌进行了表征。结果表明，最优合成条件为：AA/BT质量比为8/1，微波辐射功率为720 W，AA中和度为80 %，交联剂N,N′亚甲基双丙烯酰胺含量为0.02 %，引发剂过硫酸钾含量为0.8 %;XRD分析表明BT层间距离增大，AA单体进入BT层间，形成交联结构;SEM分析表明复合高吸水树脂是多孔结构;该复合高吸水树脂的吸蒸馏水最高倍率是1312 g/g，吸生理盐水最高倍率是320 g/g，具有较快的吸水速率，吸水溶胀过程符合一级动力学，并具有良好的热保水性能。

Study on Structure and Properties of PAA-Na/BT Composite Superabsorbent Resin Synthesized Under Microwave Irradiation

Bentonite/polyacrylic acid composite superabsorbent was prepared via microwave irradiation.The structure and morphology were analyzed by FTIR,XRD,and SEM.The effect of the preparation conditions on absorption of water was investigated.The optimal conditions were that the weight ratio of bentonite to AA was 8/1,microwave power was 720 W,neutralization degree was 80 %,the mass fraction of initiator and cross-linker were respectively 0.02 % and 0.8 %.XRD showed that the distance between the silicate layers of bentonite was increased,the monomer was intercalated into the bentonite layer and formed a cross-linked structure.SEM showed that porous products were easily obtained through microwave irradiation.The characterization of synthesized high-absorbent resin showed that the maximum water absorbency was 1312 g/g in distilled water and 320 g/g in 0.9 % NaCl,respectively.The water absorption rate was high,and the swelling processes of the composites agreed with first-order kinetics,and the retain water of the composites was temperature dependent.