聚乙烯醇/聚丙烯酸钠/Zn0.2Fe2.8O4复合水凝胶的制备及其溶胀行为

将水溶性纳米Zn0.2Fe2.8O4(ZFO)粒子、用氢氧化钠(NaOH)中和的丙烯酸(PAAS)加入一定量的聚乙烯醇(PVA)水溶液中分散均匀,再加入引发剂过硫酸钾、交联剂N,N’-亚甲基双丙烯酰胺引发聚合,制备了PVA/PAAS/ZFO水凝胶。采用傅里叶红外光谱仪(FTIR)、透射电子显微镜(TEM)对其组成和结构进行表征,并系统研究了复合水凝胶在不同溶剂中的溶胀性能。结果表明,纳米ZFO粒子均匀分散在PVA/PAAS凝胶网络中,纳米ZFO粒子的加入使水凝胶的溶胀速率和平衡溶胀度先增加后减小,在纳米ZFO含量为1%时达到最大;在不同浓度的电解质溶液和不同pH值的溶液中进行溶胀时,水凝胶表现出良好的离子浓度和p H刺激响应性。

Preparation and Swelling Behavior of PVA/PAAS/Zn0.2Fe2.8O4 Composite Hydrogel

The water-soluble nano-Zn0.2 Fe2.8 O4 particles and acrylic acid( PAAS) neutralized with NaOH was added into a certain amount of polyvinyl alcohol( PVA) aqueous solution and dispersed uniformly. Then initiator potassium persulfate and crosslinking agent N,N’-methylene bisacrylamide were added to initiate polymerization,and PVA/PAAS/Zn0.2Fe(2.8)O4 hydrogel was prepared. Their composition and structure were characterized by Fourier transform infrared spectroscopy( FTIR) and transmission electron microscopy( TEM),and the swelling properties of the composite hydrogel in different solvents were systematically studied. The results indicate that the nano-Zn0. 2Fe2.8 O4 particles are uniformly dispersed in the PVA/PAAS hydrogel network. The addition of nano-Zn0.2 Fe2.8 O4 particles increases the swelling rate and equilibrium swelling ratio of the hydrogel first increases and then decreases,and reaches the maximum when the content of nano-Zn0.2 Fe2.8 O4 is 1%. The hydrogel exhibits good ion concentration and p H stimulus responsiveness when swells in different concentrations of electrolyte solution and solutions of different p H.