| Novel controlled polymer drug delivery systems were developed via a combination of poly(N-isopropylacrylamide)( PNIPA), which can respond to the change of external environment, and β-cyclodextrin(β-CD), which can form molecular inclusion complexes. The macromolecular structures of systems which were prepared into hydrogels, interpenetration polymer networks and functional linear polymers were characterized through various advanced technologies including NMR, FTIR, Element Analysis. And the process and mechanism of controlled drug delivery was studied by using an anti-cancer drug, chlorambucil (CLB) as a model compound, to understand the supra-molecular inclusion and the related drug release behavior of polymers in according with the different experimental conditions.To synthesize qualified polymer drug delivery systems, two reactive β-CD based monomers carrying vinyl carboxylic acid groups were first synthesized via reaction of maleic anhydride (MAH) with β-CD, and with β-CD/epichlorohydrin resin (β-CD-EPI), respectively. By copolymerization of these monomers with N-isopropylacrylamide (NIPA), two novel hydrogels, MAH-β-CD/NIPA and MAH-β-CD-EPI/NIPA both having pH and temperature sensitivities plus molecular inclusion ability were obtained by free radical polymerization in aqueous solution. The element analysis, infrared spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and swelling, experiments were employed to character the β-CD modified monomers and their copolymers. The results show that both MAH-β-CD and MAH-β-CD-EPI have lower reactivity with NIPA, and the resin's equilibrium swelling ratio (ESR) can be affected by different pH, temperature and ionic strength. It was observed that MAH-β-CD/NIPA hydrogel, containing higher concentration of -COOH, exhibits better temperature sensitivity under pH 7.4. However, MAH-β-CD-EPI/NIPA hydrogel possesses higher swelling ratio and better mechanical strength compared to MAH-P-CD/NIPA hydrogel. Besides, NIPA/MAH-β-CD-EPI hydrogel can also keep much better temperaure and pH sensitivities in response to some external stimuli.The art of synthesis of β-CD/EPI hydrogel was conducted by reaction of β-CD with epichlorohydrin (EPI). DSC was employed to probe the process and mechanism of water diffusion into this resin's matrix. And the different water states in the hydrogel were studied. These states can be classified into nonfreezing bounded water, freezable bounded water and free water after reaching an equilibrium for hydrogel. As β-CD/EPI hydrogel has a low ESR, therefore, in order to obtain a higher ESR value, aninterpenetrating polymeric network (IPN) by incorporating a small amount of PVA into (β-CD-EPI-PVA)/NIPA network was synthesized. The synthesis route is to disperse NIPA monomer into the β-CD-EPI-PVA matrix first, and then, to polymerize and crosslink them in situ. Infrared spectroscopy, element analysis, DSC, TGA and swelling measurements were used to characterize the network structures and related physical properties. The results show that although ESR of the β-CD-EPI-PVA network decreases gradually with the increase in temperature, but for its IPN system, the volume phase transition temperature( Tv) can sensitively exist at about 33In order to obtain a linear polymer contining both PNIPA and β-CD, poly(NIPA-co-GMA) and EDA-β-CD were synthesized in accordance with the macromolecular design. Poly(NIPA-co-GMA) was obtained by copolymerization of NIPA with GMA (glycidy mathacrylate), and EDA-β-CD was obtained by reaction of mono-6-OTs-β-CD with EDA ( ethylenediamine). Then, a novel linear polymer, poly(NIPA-co-GMA)/ EDA-β-CD, can be synthesized by reaction of poly( NIPA-co-GMA) with EDA-β-CD. Particularly, it was found that as all epoxy groups in the main chain of poly(NIPA-co-GMA) could not be reacted out via amino groups in EDA-β-CD, the addition of small amount of reactive agent containing amino group is necessary for keeping a linear polymer at the end of polymerization. Poly(NIPA-co...
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