Preparation And Research Of The Organic Polymer/silica Hybrid Materials

The work of this paper is using in-situ polymerization technology preparation PVA/SiO₂ hybrid material and regioselection molecular mixing technology preparation PS/SiO₂ hybrid material.Explore two restrictive factors affect material performance: inorganic particle dispersity and interface interaction between organic matrix and inorganic particle in organic-inorganic materials, design and control the hybrid material structure and performance based on molecular design. The main research results obtained as follows:1,TEOS as the precursor with St?br method to preparation nano SiO₂, than copolymerization with VAc produce PVA/SiO₂ hybrid material. FT-IR results demonstrate that as product is SiO₂ and PVA. PVA/SiO₂ hybrid material TG-DTA results show that the thermal stability of the materials with a certain degree of increase, but its thermal degradation mechanism and can't change. Meanwhile, Silica contents in the hybrid materials are given by TG grammar. For the material under non-isothermal scanning DSC analysis shows that the join widened with SiO₂ of PVA glass transition temperature range, PVA/SiO₂ hybrid material with the wider than PVA Tg range. PVA and PVA/SiO₂ nano complex molten Endothermic peak curve suggests that the silica nanoparticles has low impact on crystallite size when silica content is low and obstructs the crystallization of the PVA when the silica content is high. Moreover,the low amount of silica nanoparticles would only decrease the degree of crystallinity, but the large amount of silica nanoparticles would obstruct the crystallization of the matrix and result in a decrease in both crystallinity and crystallite size. From XRD, FT-IR and DSC data income crystalloid did for the same trend, the formation of grain boundaries on the particle surface may be complex with crystallinity decline when the content of SiO₂ rising gradually. The SEM results of hybrid material can see SiO₂ particles can more uniform distribution in matrix with PVA. The mechanical properties of hybrid materials, such as tensile strength, tensile modulus with the addition of SiO₂ is improved, and understandable additionof SiO₂ changed material glass transition temperature and crystallization properties, and elongation at break show downward trend when the fill of SiO₂.2,A series of organic–inorganic hybrid materials have been prepared by copolymerizing styrene and methacrylic acid 3-(trimethoxysilyl)propyl ester (MSPMA) via the sol–gel process. The alkoxysilane-containing copolymer precursors were synthesized by free-radical copolymerization of styrene with methacrylic acid 3-(trimethoxysilyl)propyl ester (MSPMA), at several feeds. The copolymer precursors were then hydrolyzed and condensed to generate PS/SiO₂ hybrid sol–gel materials. The hybrid copolymers possess excellent optical transparency. The compositions of the copolymers precursors and their hybrid copolymers were determined from FT-IR spectroscopic method and silicon contents estimated gravimetrically; respectively. The reactivity ratios were determined by the Kelen-Tüd?s graphical method. The copolymer precursors and their hybrid copolymers were characterized by FT-IR spectra, and TGA thermograms. Chemical structural effect on the morphology and thermal properties was investigated with SEM. It was found that covalently between copolymer and silica has beneficial for thermal stability. Moreover, MSPMA could be hydrolyzed to methacrylic acid and ester-interchanged to silyl methacrylate during heat treatment. This also enhances the compatibility between the copolymer and silica. The thermal properties of the PS/SiO₂ hybrid copolymers are improved as silica content increase. However, the presence of silyl ester groups, which were formed during heat treatment, would reduce the thermal stability of the hybrid copolymers.3,The model construction of PVA/SiO₂ and PS/SiO₂ hybrid material based on the experimental design and results of each hybrid material, provides experimental and theoretical support for the hybrid material design and preparation.