聚丙烯酸钠-高岭土复合高吸水性树脂的制备及结构表征

采用静态水溶液法制备了高填充比例的聚丙烯酸钠-高岭土复合吸水性树脂(简称复合树脂),考察了聚合温度、丙烯酸单体的含量、丙烯酸中和度、引发剂和交联剂的用量、高岭土含量对复合树脂吸水率的影响,并用傅里叶变换红外光谱、扫描电镜、热重和示差扫描量热法对复合树脂的微观结构进行了表征。实验结果表明,复合树脂的最佳制备条件为:聚合温度70℃,丙烯酸单体的质量分数30%,丙烯酸中和度70%,引发剂占单体的质量分数0.1%,交联剂占单体的质量分数0.08%,高岭土占单体的质量分数50%;在此条件下制备的复合树脂对蒸馏水的吸水率为834 g/g,对质量分数0.9%的NaC l溶液的吸水率为81 g/g。傅里叶变换红外光谱和扫描电镜表征结果表明,复合树脂是一种典型的海-岛结构,丙烯酸和高岭土之间存在接枝聚合反应。

Synthesis and Characterization of Sodium Polyacrylate -Kaolin Composite Super Absorbent Resin

(Sodium polyacrylate)-kaolin composite super absorbent resin(composite resin)with high kaolin content was synthesized by static aqueous solution polymerization.Effects of polymerization temperature,monomer content,neutralization degree of acrylic acid,cross linker dosage and initiator dosage on absorbency of composite resin were studied.The obtained optimal polymerization conditions were 70℃,mass fraction of acrylic acid monomer 30%,neutralization degree of acrylic acid 70%,mass fraction of initiator to monomer (0.1%),mass fraction of crosslinker to monomer 0.08% when mass fraction of kaolin to monomer was 50%.Absorption rates of the above-mentioned composite resin to distilled water and 0.9% NaCl solution were 834g/g and 81g/g,respectively.Microstructure of the composite resin was characterized by means of IR,SEM,DSC and TG.The composite resin belonged to typical"sea-island"structure.Kaolin was grafted into sodium polyacrylate,and the two were binded strongly with each other.