| Besides the mechanical property, the surface property of polymeric materials plays an increasingly important role in the industrial and biomedical fields. The polymers commonly have a hydrophobic and chemically inert surface. As for the functional polymer microspheres, the surface property is also critical for their applications. In this thesis, some functional groups were successfully introduced onto the polymer surface by grafting method; meanwhile a novel kind of polymer microspheres with functional groups were prepared by dispersion polymerization of functional monomers.Maleic anhydride (MAn) was chosen as a desirable functional monomer due to the strong polarity and high reactivity of the anhydride groups. It is well known that MAn is difficult to undergo homopolymerization because of the steric hindrance. However, MAn has strong tendency to undergo alternating copolymerization with some electron donating monomers by a charge-transfer-complex (CTC) mechanism. Based on this fact, butyl vinyl ether (BVE) and N-vinylpyrrolidone (NVP) were introduced into the grafting system to facilitate the reaction process. Similarly, through the dispersion copolymerization of vinyl acetate (VAc) and MAn, the functional polymer microspheres were prepared.As for the MAn/BVE system, the surface grafting on the polypropylene (PP) film was facilely achieved by one-step method and two-step method. The polymerization features, kinetics, mechanism and the property of the graft-modified surface were investigated systematically.It has shown that the surface photografting of MAn/BVE is a desirable approach to rapid surface modification of polymeric materials. The grafting efficiency (Eg) of the photoinitiators benzildimethylketal (BDK), benzophenone (BP) andisopropylthioxanthone (ITX) has the following sequence: BP > ITX > BDK. Far UV (200-300 nm) plays a crucial role in surface photografting. The affinity between the substrate and solvents has a positive effect on the surface grafting process. The activation energy of total photopolymerization is 6.04xl03 kJ/mol while the value of graft polymerization is 29.3xlO3 kJ/mol, which means that the photografting process is greatly affected by reaction temperature. The surface photografting of MAn/BVE can readily proceed even in the absence of any photoinitiator, which is possibly resulted from the self-initiation of MAn through the excited dimmer. Both grafting yield (Yg) and Eg reached a maximum at 1:1 molar ratio of MAn to BVE. This result strongly confirms that the alternating copolymerization of these binary monomers leads to the facile surface photografting. The formation of CTC in MAn/BVE system was determined by both UV-vis spectroscopy and *H NMR spectroscopy; further, the equilibrium constant of CTC was determined by Hanna-Ashbaugh equation.In the two-step grafting method, the semipinacol dormant groups were firstly introduced on the film surface by UV irradiation. The dormant groups were measured by UV-vis spectroscopy. Secondly, the dormant groups were activated thermally and cleaved from the substrate; thus the surface free radicals were formed and the graft reaction was initiated in the presence of monomers. At 1:1 molar feed ratio of MAn to BVE, Yg reached a maximum value, which also indicates that the alternating copolymerization is favorable to surface photografting. It has been surprisingly found that the surface grafting was remarkably promoted by adding some acetone as a cosolvent. The grafting process has somewhat living polymerization feature, which may result from the reversible deactivation of semipinacol radicals to the growing graft chains.The chemical composition of grafted surface was measured by FT-IR, and the surface morphology was observed by SEM. It was found that the hydrophilicity of the grafted surface was greatly improved; the contact angle against water decreased from the original 99° to less than 20° . The surface-grafted anhydride groups could facilely undergo a series of post reactions such as hydrolysis, saponification, esterification, etc., which is favorable to further functionalization of the grafted surface.As for MAn/NVP system, the surface photografting was successfully achieved both on PP film and non-woven fabrics. It was found that Yg and Eg reached a maximum at 1:1 molar ratio of MAn to NVP, which also means that MAn/NVP alternating copolymerization leads to the facile surface photografting. ATR-IR analysis show that the graft chains distribute from outer surface to inner surface to some extent. MAn and NVP also synergistically promote the surface hydrophilicity; the ability of some species to improve the hydrophilicity follows this sequence: MAn < NVP < MAn/NVP (unhydrolyzed) < MAn/NVP (hydrolyzed). The surface-grafted pyrrolidone groups could readily undergo complexation with iodine, thus resulting in a novel antibacterial material. The antibacterial activity of the modified film against Escherichia coli (Gram negative), Staphylococcus aureus (Gram positive) and Candida albicans (fungus) was investigated. The results show that the modified material has a desirable antibacterial property, with broad spectrum and high efficiency.As for MAn/VAc system, a novel dispersion polymerization without adding stabilizer was discovered, which yields uniform polymer microspheres with controllable sizes. The polymerization features of the stabilizer-free dispersion polymerization, the morphology of the microspheres and some mechanistical aspects were investigated.It was found that the stabilizer-free dispersion polymerization of MAn/VAc is a relatively rapid process. The activation energy of the polymerization is about 69.5 kJ/mol. The yield of copolymer reached a maximum at around 1:1 molar ratio of MAn to VAc. The alternating structure of the copolymer was confirmed by both titration method and 13C NMR method. The formation of CTC in MAn/VAc system was determined by UV-vis spectroscopy. The existence of reactive anhydride groups would greatly favor the functionalization of particle surface, and thus may open up numerous potential applications. Moreover, this novel type of polymer microspheres has good solubility in common nontoxic (or less toxic) solvents such as water, alcohols and alkyl ketones.The stabilizer-free dispersion polymerization of MAn/VAc can readily proceed over...
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