| Summary: | 碩士 === 大同大學 === 化學工程學系(所) === 98 === partI
A novel four-arm biodegradable compound (I) was prepared from pentaerythritol (PTOL) as initiator, stannous octoate Sn(Oct)2 as catalyst, glycolide (GA), and lactide (LA) via ring-opening polymerization. The compound (I) containing terminal hydroxyl group was reacted with acryloyl chloride to obtain the monomer (II) containing terminal vinyl group. The monomer (II) as crosslinker was copolymerized with thermosensitive monomer, N-isopropyl acrylamide (NIPAAm) to prepare a series of biodegradable four-arm thermosensitive hydrogels. The results show that the swelling ratios decrease with an increase of the crosslinker content in the hydrogels. The gel strength and gel modulus of hydrogels are also increased with increasing of crosslinker content. But, the drug release decreases with an increase of the crosslinker content in the hydrogels. The effects of crosslinker content on the drug release and the degradation cycle of the hydrogels containing PLGA were investigated. In this study, toxicity of the monomer and the hydrogels are also tested before and after biodegradation in order to confirm whether they can apply in the body or not.
partII
A novel six-arm biodegradable compound (I) synthesized from sorbitol as initiator, stannous octoate Sn(Oct)2 as catalyst, and glycolide (GA), and lactide (LA) via ring-opening polymerization. The compound (I) containing terminal hydroxyl group was reacted with acryloyl chloride to obtain the monomer (II) containing terminal vinyl group. The monomer (II) as crosslinker was copolymerized with thermosensitive monomer, N-isopropyl acrylamide (NIPAAm) to prepare a series of biodegradable six-arm thermosensitive hydrogels. The results show that the swelling ratios decrease with an increase of the crosslinker content in the hydrogels. The gel strength and gel modulus of the hydrogels are also increased with an increase of the crosslinker content. But the drug release decreases with an increase of the crosslinker content in the hydrogels. The effect of crosslinker content on drug release of the hydrogels and the biodegradation cycle of the hydrogels containing PLGA were investigated. In addition, the gels crosslinked by the same concentration of crosslinker (four or six-arm) or the same number of vinyl groups of crosslinker were designed to compare swelling ratio and drug release behavior, the results show that swelling ratio of the hydrogels and drug release behavior follow the rule of crosslinking density. In this study, toxicity of the monomer and the hydrogels are also tested before and after biodegradation to confirm whether they can apply in the body or not.
partIII
In this study, poly(lactide-co-glycolide) (PLGA) as matrix was used to prepare microspheres by spray drying process. The effect of different spray drying process parameters on the yield of microspheres was investigated. The results showed that spray drying can prepare 1 ~ 30 μm diameter of the microspheres (microspheres).
SEM analysis shows that the pores of the microspheres prepared by spray drying process are the interconnected structure in the inside microspheres but their surface structures show dense layer; the way of gathering is flocculation. The yield analysis showed that the yield of microspheres can be improved by adjusting different ratios of solvents and temperatures of inlet and outlet. The maximum yield can be achieved about 53%.
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