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

Synthesis and Thermosensitivity of Poly( N-isopropylacrylamide)/Hydrotalite Hydrogel

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。

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.