STUDIES ON PREPARATION AND PROPERTIES OF ORGANIC HYBRID HYDROGELS

• Main Authors: Sung-Chuan Lee, 李松泉
• Other Authors: Wen-Fu Lee
• Format: Others
• Language: en_US
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/34255416614949672889

碩士 === 大同大學 === 化學工程學系(所) === 92 === Organic hybrid gels based on poly(N-isopropylacrylamide) P(NIPAAm) and a natural polymer, gelatin, through two-step crosslinking with genipin (GP) or glutaraldehyde (GA), respectively, were prepared. The effect of gelatin content on the swelling behaviors and physical properties of these hybrid gels were investigated. Results indicated that the swelling ratio decreases with an increase of the content of gelatin in these hybrid gels. The swelling ratio for the gel crosslinked by genipin was significantly smaller than that gel crosslinked by glutaraldehyde. The results also showed that the gel crosslinked with genipin has a higher crosslinking density (ρx) and a higher gel strength. In second part, the objective in this study is to investigate the effect of the crosslinking agent of gelatin in the organic hybrid gels on the drug release behavior for the drugs with different molecular size and charges. Results indicated that the release ratio of sulfanilamide, caffeine and vitamin B12 in the hybrid gels was not affected by the ionicity of hybrid gels. But it increased with increasing of the swelling ratio. The phenol red (anionic) strongly interacted with cationic hybrid gels, so the phenol red release ratio in hybrid gels was very low. On the other hand, neutral red (cationic) was only adsorbed on the skin layer of the cationic hybrid gels due to the charge repulsion, and released rapidly. Therefore the release ratio was the highest for hybrid gels to cationic drug. Besides, the release ratio for the gel crosslinked by genipin was significantly smaller than that gel crosslinked by glutaraldehyde. In third part, a series of hybrid nanocomposite hydrogels based on gelatin and intercalated hydrotalcite (IHT), crosslinked with glutaraldehyde, were prepared in this study. The microstructures of the IHT and sample gels were identified by x-ray diffraction (XRD). Swelling behaviors and physical properties of these hybrid gels were investigated. XRD results indicated that the exfoliation of IHT was achieved in the hybrid nanocomposite gels. The results indicated that adding a small amount of IHT could effectively decrease the swelling ratio of the hybrid gels, but adding excess IHT could increase the swelling ratio of the nanocomposite hybrid gels. Besides, the crosslinking densities (ρx) of the present gels were varied with IHT content and swelling ratio of the gels. The drug release behaviors of the present gels were also investigated.