聚N-异丙基丙烯酰胺/类水滑石复合水凝胶的制备及温敏性

摘要

To obtain thermosensitive and injectable hydrogels , hydrotalcite ( LDHs) and N-isopropylacrylamide ( NIPA) were used to synthesize a series of PNIPA/LDHs hydrogels by free radical polymerization .The properties of PNIPA/LDHs hydrogels were characterized by thermal gravimetric analyzer (TGA), differential scanning calorimetry(DSC) and scanning electronic microscopy (SEM).The results show that the synthesized hydrogels have a reversible sol-gel transformation around 33 ℃.LDHs mass ratios have no influence on the temperature and time of gelation .The thermal stability of PNIPA/LDHs is remarkably increased by the addition of LDHs.The endothermic peak of PNIPA/LDHs hydrogels increases with the increase of LDHs mass ratios and the molar ratio of Mg to Al .PNIPA/LDHs hydrogels have porous structures .%以类水滑石(LDHs)和N-异丙基丙烯酰胺(NIPA)为原材料,采用自由基引发聚合制得了有机无机PNIPA/LDHs温度敏感复合水凝胶.通过热重分析仪(TGA)、示差扫描量热仪(DSC)和扫描电子显微镜(SEM)等技术手段表征了材料的结构和性能.结果表明,PNIPA/LDHs复合水凝胶在33℃左右可实现溶胶-凝胶的可逆性变化,LDHs质量分数基本不影响复合水凝胶的胶凝化温度和胶凝时间.LDHs添加可使PNIPA/LDHs复合水凝胶的热稳定性较NIPA有大幅度提升.随LDHs质量分数及n(Mg):n(Al)的增加,复合凝胶的吸热峰值稍有增加.所合成PNIPA/LDHs复合水凝胶表面粗糙不平,具有一定的孔洞结构.