P(AM-AA)/PVA/PAMPS双网络水凝胶的制备与性能研究

Preparation and Properties of P(AM-AA)/PVA/PAMPS Double Network Hydrogels

以过硫酸钾(K2S2O8)为引发剂,以丙烯酸(AA)和丙烯酰胺(AM)为单体,以N,N’-亚甲基双丙烯酰胺(MBAA)为交联剂,以聚乙烯醇(PVA)和聚2-丙烯酰胺基-2-甲基丙磺酸(PAMPS)为互穿高分子链,制备了共价交联半互穿网络水凝胶(sIPN)。随后通过冷冻–恢复室温三次循环,PVA链形成微晶交联网络,获得共价-微晶双网络水凝胶(CMDN)。再将水凝胶浸泡于氯化铁溶液中,通过阴阳离子静电吸附形成离子交联网络,获得P(AM-AA)/PVA/PAMPS共价–微晶–离子双网络(CMIDN)水凝胶。拉伸性能测试表明0.2PAMPS-0.4FeCl3水凝胶具备最好的力学性能,拉伸强度为3.90 MPa,断裂伸长率为278.0%。CMIDN水凝胶具有良好的还原响应形状记忆性能,在1 M抗坏血酸溶液中,0.2PAMPS-0.4FeCl3与0.5PAMPS-0.4FeCl3水凝胶分别可在120 min和150 min内恢复起始形状。

Covalent cross-linking semi-interpenetrating network hydrogels(sIPN)were fabricated with po-tassium persulfate(K2S2O8)as initiator,acrylic acid(AA)and acrylamide(AM)as monomers,N,N’-methylenebisacrylamide(MBAA)as crosslinking agent,with poly(vinyl alcohol)(PVA)and poly(2-acrylamide-2-methyl propane sulfonic acid)(PAMPS)as interpenetrating polymer chains.Covalent-microcrystalline double network(CMDN)hydrogels were obtained by freeze-thaw method,which could promote the formation of microcrystalline crosslinking of PVA.Then P(AM-AA)/PVA/PAMPS covalent-microcrystalline-ionic double network(CMIDN)hydrogels were obtained by immersing CMDN hydrogels in ferric chloride solutions with different concentrations.The tensile tests showed that 0.2PAMPS-0.4FeCl3 hydrogel showed the best mechanical properties,with a tensile strength of 3.90 MPa and a breaking elongation of 278.0%.After being immersed in 1 M ascorbic acid solution,0.2PAMPS-0.4FeCl3 and 0.5PAMPS-0.4FeCl3 hydrogels could recover to their original shape within 120 min and 150 min,respectively.