新型互穿网络超大孔水凝胶的制备及其性能的研究

【作者】 敖海勇；

【导师】 黄妙良； 吴季怀；

【作者基本信息】 华侨大学 ， 材料学， 2008， 硕士

【摘要】 水凝胶由于具有良好的吸水、保水及生物相容性等优良性能,在农业、工业、生物医药等领域具有广阔的应用前景而倍受人们关注。与普通水凝胶相比,互穿网络超大孔水凝胶(SPIHs)具有较快的溶胀速率和良好的机械性能,成为当前研究的热点。本文利用发泡技术将超大孔引入水凝胶结构中;采用两种互穿网络技术来提高超大孔水凝胶的凝胶强度,制备了三种互穿网络超大孔水凝胶;利用DSC、FT-IR、SEM等分析技术对所得凝胶进行表征;研究了互穿网络超大孔水凝胶(SPIHs)性能的影响因素,并对这类水凝胶的药物释放性能进行了初步研究。主要研究内容和结果如下:以丙烯酸(AA)、丙烯酰胺(AM)为基体,丙烯酰胺为预聚物,利用新型分步法和发泡技术制备了聚(丙烯酸-丙烯酰胺)/聚丙烯酰胺互穿网络超大孔水凝胶。DSC和SEM分析结果表明该凝胶具有多孔结构和互穿网络结构,孔径大小为100~200μm,属于超大孔范畴。多孔结构降低了水凝胶与水的结合力,而互穿网络能提高水凝胶与水的结合力。当基体中AA/AM为1:3、预聚物/基体为1:1时,凝胶压缩强度可达25KPa,2分钟内可达到溶胀平衡。选用乙烯基吡咯烷酮为预聚物,利用新型分步法和发泡技术制备了聚(丙烯酸-丙烯酰胺)/聚乙烯基吡咯烷酮互穿网络超大孔水凝胶。DSC分析显示SPIHs的Tm高于超大孔水凝胶(SPHs)和超大孔水凝胶复合物(SPHCs),FT-IR分析显示oligo-PVP谱图中不含C=C特征峰,说明oligo-PVP不含NVP单体;结果表明该方法成功地将互穿网络引入到超大孔水凝胶网络结构中,是制备IPN简单有效方法之一。SEM照片显示孔是相互连通的,这种相互连通的孔结构赋予了水凝胶快速溶胀的性能。当AA/AM为1:3、预聚物/基体为1:1时,凝胶压缩强度为20KPa,3分钟内可达到溶胀平衡。以壳聚糖为添加物,N,N’-亚甲基双丙烯酰胺、戊二醛为复合交联剂,利用IPN同步法和发泡技术制备了聚(丙烯酸-丙烯酰胺)/壳聚糖互穿网络超大孔水凝胶。采用DSC、FT-IR和SEM等分析技术进行了表征,研究了水凝胶的溶胀行为和凝胶压缩强度。实验结果表明,该互穿网络超大孔水凝胶具有较快的溶胀速率和较好的凝胶强度。以牛血红蛋白为模拟药物,人工肠液和人工胃液为溶出介质,聚(丙烯酸-丙烯酰胺)/壳聚糖互穿网络超大孔水凝胶为药物载体,初步研究了互穿网络超大孔水凝胶的药物释放性能,并探讨了药物和载体的相互作用。结果表明,互穿网络超大孔水凝胶在人工肠液中具有较快的药物释放性能;FT-IR分析结果表明,牛血红蛋白与SPIHs未发生化学作用,不存在共价连接,只是通过氢键等物理作用相连接。更多还原

【Abstract】 Hydrogels has attracted much attention because of their excellent properties, such as higher water absorbency、water retention and good biocompatibility, and their applications in the fields of agriculture, industry and bio-Medicine. In comparison with common hydrogels, superporous IPN hydrogels (SPIHs) possessed both fast swelling property and higher mechanical strength, has been paid more and more attention. Three different superporous IPN hydrogels (SPIHs) were prepared by two different IPN technologies and foaming technique. The prepared SPIHs were characterized by DSC、FT-IR and SEM, and the properties of SPIHs were studied. In addition, the preliminary study of the hydrogel as a drug delivery system has been performed. The main contents and results are as follows:With acrylic acid (AA) and acrylamide (AM) as matrix, AM as prepolymer, P(AA-co-AM)/PAM superporous IPN hydrogels were prepared by the novel two-step polymerization and foaming technique. The results of DSC and SEM analysis indicated the obtained hydrogel possessed both porous structure and IPN structure, and the pore size was 100~200μm, belonged to superpores. The porous structure reduced the water retentivity of hydrogel and the IPN structure could strengthen the water retentivity of hydrogel. When the AA/AM weight ratio was 1:3 and prepolymer/matrix weight ratio was 1:1, the compressive strength of hydrogel was 25KPa, and hydrogel could swell to equilibrium in two minutes.With N-Vinylpyrrolidone (NVP) as prepolymer, P(AA-co- AM)/PVP superporous IPN hydrogels were prepared. DSC thermograms showed the melting temperature (Tm) of the SPIHs was higher than that of SPHs and SPHCs, FT-IR spectra of oligo-PVP didn’t contain the feature peak of C=C, indicating that oligo-PVP didn’t contain NVP monomer. The results indicated that the novel two-step polymerization, as one of the methods to make IPN structure effectively, can introduce the IPN into the structure of hydrogels. The SEM picture showed that pores are interconnected with each other. The interconnecting porous structure endowed SPIHs with fast-swelling property. The compressive strength of hydrogel was 20KPa with AA/AM weight ratio 1:3 and prepolymer/ matrix weight ratio 1:1, and hydrogel could swell to equilibrium in three minutes.With chitosan as hybrid agent, N,N’-methylenebisacrylamide and glutaraldehyde as the multiple crosslinking agents, P(AA-co-AM)/ Chitosan superporous IPN hydrogels were prepared and characterized by DSC、FT-IR and SEM. the swelling behavior and compressive strength of the samples were studied. The results indicated the obtained SPIHs possessed both excellent property of fast swelling and fairly high mechanical properties. A drug release experiments of the P(AA-co-AM)/Chitosan superporous IPN hydrogels were performed prelimarily wth bovine erythrocytes hemoglobin (Hb) as model drug and artificial intestinal juice、artificial gastric juice as dissolution medium. The results showed that SPIHs can release drug quickly in artificial intestinal juice because of the open porous structure. The chemical bonding between Hb and SPIHs was not observed from FT-IR analysis, suggested that Hb interacts with the SPIHs by physical force such as hydrogen bond.更多还原