双网络POSS/羧甲基纤维素/PNIPAm杂化水凝胶的制备和性能研究

FABRICATION AND PROPERTIES OF DOUBLE NETWORK POSS /CMC /PNIPAM HYBRID HYDROGEL

八氨丙基齐聚倍半硅氧烷(POSS-NH2)是以立方结构Si-O-Si为核、顶角的8个氨丙基为壳的有机无机杂化纳米粒子,其粒径大小与大分子链的尺度相当.羧甲基纤维素(CMC)凭借其可再生性、可生物降解性、生物相容性和水溶性成为水凝胶制备的首选材料.本研究利用POSS-NH2中的NH2基团和CMC中的COOH基团之间的氢键作用形成POSS-CMC嵌段共聚物,继而由于POSS纳米粒子的聚集而交联形成新型的POSS/CMC水凝胶.并在此基础上,设计制备了双网络POSS/CMC/PNIPAm杂化水凝胶.通过红外光谱、原子力显微镜(AFM)、扫描电子显微镜(SEM)、流变仪等测试手段分别对所制的POSS纳米粒子、POSS/CMC和POSS/CMC/PNIPAm水凝胶的结构和性能进行了表征.结果表明,所制备的八氨基POSS纳米粒子的粒径为4 nm,并成功制备了双网络POSS/CMC/PNIPAm杂化水凝胶,并且其具有优异机械性能、较好的溶胀性能和快速的温度响应性.

A novel polyhedral oligomeric silsequioxane/carboxymethyl cellulose （POSS/CMC） hybrid hydrogel was first fabricatied by the aggregation of POSS-NH2 nanoparticles and the formation of POSS-CMC hybrid block copolymers,which was driven by the hydrogen bonding interactions between the amino groups of POSS-NH2 and the carboxyl groups of CMC. Novel double network POSS/CMC/PNIPAm hybrid hydrogel was further designed and fabricated by the synthesis of the second net work of poly-N-isopropylacrylamide. The structure and morphology of the obtained POSS nanoparticles and POSS/CMC/PNIPAm hybrid hydrogel were respectively characterized by Fourier transformation infrared spectroscopy （FTIR）, atom force microscopy （AFM） , scanning electronic microscopy （SEM） , rheometry and so on. Meanwhile, the mechanical and swelling properties of double network POSS/CMC/PNIPAm hybrid hydrogel were also studied. The results presented that the obtained POSS-NH2 nanoparticles had a diameter of 4 nm. Double network POSS/CMC/PNIPAm hybrid hydrogel had been successfully fabricated, and it had good mechanical properties, swelling ratio and more rapid temperature response than PNIPAm hydrogel.