聚(N-异丙基丙烯酰胺)/海藻酸钠/粘土复合水凝胶的制备及溶胀动力学研究

Study on the preparation and the swelling kinetics of Poly(N-isopropylacrylamide)/Sodium Alginate/Clay Composite Hydrogel

以无机粘土为交联剂制备了聚(N-异丙基丙烯酰胺)/海藻酸钠/粘土(PINPA/SA/Clay)复合水凝胶,通过红外光谱、X射线衍射对凝胶的结构进行了表征,结果表明:粘土的结晶结构已被破坏,粘土规整的片层被剥离并在凝胶中无序分布,起到交联剂的作用;随粘土含量的增加,凝胶网络交联密度增加,溶胀速度下降。在不同温度下对不同粘土含量的凝胶进行了溶胀动力学测试,表明在低于其相转变温度时,凝胶的扩散类型为non-Fickian扩散。

A new kind of composite hydrogel based on the Sodium Alginate （SA） and Poly（N-isopropylacrylamide） （PNIPA） cross-linked by inorganic clay was successfully synthesized. The structures of the hydrogels were characterized by means of FT-IR and XRD. The results show the regular crystal structures of clay were destroyed and the clay platelets were exfoliated and dispersed randomly in the hydrogels, which acted as a muhifunctional crosslinker in the hydrogels. As the clay contents increased, the crosslinking density of hydrogel increased, which led to the decreasing of the swelling rates of the hydrogels. The swelling kinetics of PINPA/SA/Clay hydrogel with different clay contents were studied at the different temperature. The transport mechanism of PINPA/SA/Clay hydrogel below its LCST is non-Fickian transport.