| The novel grafting methods for polymer surface modification, as a combination of chemical and physical methods, can bring forth a sound and extensive influence on the commercial application and scientific investigation. The current work introduced emulsion/microemulsion photografting polymerization into the surface grafting modification. In this way, even the general polymers, as polymethyl methacrylate (PMMA), polyacylamide (PAM), poly (N-vinyl pyrrolidone) (PVP) and polybutyl methacrylate (PBA), could be formed into colloidal nanoparticles and used as building blocks for the construction of more complicated structures. In this course, these building blocks or the assembled structures were also tethered onto the polymer surface via UV initiated grafting reaction to realize the surface physical modification. This surface photografting system was thought to bring a new system for the surface grafting, and exploit a new way for the patterning modification of polymer surface, moreover, be of great value for the study on emulsion/microemulsion polymerization in confined conditions.In the work, opaque methyl methacrylate/1, 2-divinyl benzene (MMA/DVB) emulsion, transparent MMA/DVB microemulsion and N-vinyl pyrrolidone/N, N'-methylene-bis-acrylamide (NVP/MBA) inverse microemulsion were used in polymer surface photografting polymerization, and the morphologies with nanoparticles tethered on the polypropylene film's surface were obtained. The grafting efficiency in emulsion grafting system is high (80 %) and the reaction is faster than that in a solution grafting system with the same molar ratio of MMA/BP, which is in favor of the forming surface high-density grafting structures. The size of the graftingparticles is far smaller (30-50 nm) than that of the particles collected from the inter-film emulsion (60-200 nm). Furthermore, the application of sequential two-step method in the surface photografting MMA/DVB microemulsion caused the grafting particles more complete and the size distribution of grafted particles is narrower. This method, in addition, realized the control over the thickness of the grafting layer. A monolayer of grafting nanoparticles was obtained. Based on above study, the NVP/MBA inverse microemulsion was successfully used in surface photografting polymerization, and morphology with surface tethered bimodal particles was obtained, which was probably the reason for the significant superhydrophilicity (Contact Angle less than 5°) after modification. Since the size of formed surface particles was in the scale of nanometer, the transparency of the polymer films had been little influenced after modification. Moreover, the nanoparticles effectively prevented the transformation of surface polymer chains down to the inner layer, which thereby remained the surface superhydrophilicity for a long term.Based on the above research, a two-monomer microemulsion containing MMA/NVP was polymerized under UV light with the initiation of BP/triethylene. As the result, the building blocks (PMMA nanoparticles) and the assembled structures (PMMA-PVP solid or hollow particles) were prepared continuously in the process of photo-polymerization. Moreover, the formation of the assembled supermolecular structure could be changed from solid sphere into hollow sphere by controlling the ration of MMA/NVP in the microemulsion. Furthermore, these kinds of the assembled structures(PMMA-PVP solid or hollow particles) were successfully grafted on the polymer surface with the same reaction system. Since the PVP used in the assembled structure, Ag particles were then complexed into the grafting particles. This work did a positive exploration to the construction of surface superstructures.In addition, the preparation of other kinds of building blocks was done as supplement to the above assembly superstructures. Under UV irradiation, the primary nanoparticles were prepared by BP/triethylene initiated photo-polymerization of MMA/DVB microemulsion. Then these nanoparticles with surface dormant groups, which could be reactivated by heated, were used as active centers to initiate the...
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