Preparation And Properties Of Novel Micro-and Nano- Structure Polymer Matrix Composites

Recently, polymer matrix composites are becoming the hotspot in materials research due to their excellent overall performance. In this paper, the preparation of polymer matrix composites and their application in optical and biological medicine fields were discussed. Light-diffusing particles (LDP)/polyacrylates composites were prepared via in situ radical polymerization, with the surface modification made the LDP better dispersed and incorporated with polyacrylate polymer chains, which showed excellent anti-glare property if applied to LED light system. A novel high level oriented assembly of zinc hydroxide carbonate nanocrystals in chitosan (CZHC) was fabricated via hydrothermal process, which showed a good antifungal activity against many kinds of fungi. The detailed content is listed as follows:(1) A facile fabrication of light diffusing film with LDP/polyacrylates composites coating for anti-glare LED application was presented. In this approach, the LDP were pretreated with H2SO4 and then modified with vinyl triethoxysilane (A-151) to make the LDP less aggregated and to graft the carbon-carbon double bond to the LDP. Then the LDP/polyacrylates composite coatings were prepared with the pretreated LDP, methyl methacrylate, butyl acrylate and acrylic acid via in situ free radical polymerization. The LDP obtained at different modification stages were characterized with FTIR and XPS. The optical properties of the film including the transmittance, haze, and the light distribution after the diffusion were characterized. And the anti-glare application of the films was studied using the LED downlight. The synergistic effect of LDP content and dispersion technique induced the uniform hemispherical surface convex micro-structure fabrication and assembly on the surface of diffusing film, and the uniformity of the surface convex micro-structure determines the homogeneity of the light distribution and higher light transmittance. When the mass ratio (LDP/polyacrylate) was 0.5, the film obtained the highest light-diffusing effect and more than 90% transmittance due to the formation of hemispherical surface convex micro-structure. The light diffusing films have excellent anti-glare property if applied to LED light system.(2) A novel high level oriented assembly of zinc hydroxide carbonate nanocrystals in chitosan was fabricated via hydrothermal process. The products obtained at different reaction stages were characterized with SEM, TEM, XRD, XPS, and TGA. The mechanism of the formation of CZHC was discussed. The antifungal activity assays of CZHC, zinc hydroxide carbonate, chitosan, chitosan simply blended with zinc hydroxide carbonate (1:1), and nano zinc oxide were investigated. The mechanism of the antifungal action of CZHC was discussed. The hybrid materials contains ca.44 wt% Zns(CO3)2(OH)6 and ca.56 wt% chitosan, showing sheetlike morphology with a thickness of 20 nm and broad in micrometer scale; nanocrystals of Zn5(CO3)2(OH)6 are uniformly and orientedly dispersed in chitosan matrix. Hydrated chitosan acts as template supporting and structure-directing reagents for the formation and assembly of zinc hydroxide carbonate nanocrystals. The antifungal activity assays exhibited that that the CZHC nanocrystals showed an antifungal activity against Cotton Verticillium, Rhizopus and Mucorales, and showed a better antifungal activity than other test samples against Rhizopus. These findings may be particularly useful for the preparation of nanocrystal-organic hybrid superstructures and antifungal applications.