Synthesis And Characterization Of Polyester/Silicon Organic-inorganic Hybrid Coating Materials

In this dissertation, in order to obtain polyester hybrid coating material with good scratch resistance, good stability and good transparency, polyester/silicon organic-inorganic hybrid polyester and coating with good dispersion of silicon compound were prepared via in situ fabrication （ISF） and in-situ sol polymerization （ISP）. The influence of silicon compound on the mechanical properties and the functional performances of polyester coatings and their films was investigated. The morphology and interaction of silicon compounds and polyester of the hybrid coatings were characterized. Meanwhile, polyester/SiO₂ composite resins and coatings were prepared and characterized via sol blending with resin as control sample. The main results obtained were listed as follows:1. Well-dispersed and transparent polyester/silicon compounds hybrid resins and coatings could be obtained via ISF and ISP. Tetraethyl orthosilicate （TEOS） had remarkable catalytic activity in the polyester polymerization system, it helps to largely shorten the etherification and polymerization time, increase reaction efficiency. According to the requirement of on transparency and fluidity of the products, it could be also concluded that the silicon concentration of 1.5%wt could be suggested as better experimental condition. 2. Silicon which was formed by in-situ hydrolysis of precursor TEOS was homogeneously dispersed into matrix polyester resins and coatings via ISF and ISP. Shape of Silicon was not regular and the equivalent size was mostly between 10nm and 200nm.3. Silicon had integrated with matrix polyester by chemical bonds in polyester/silicon hybrid resins and coatings prepared via ISF and ISP, the acting force between the matix and silicon were stronger. The reactions of precursor TEOS in the reaction system was not only hydrolysis but also reaction with polyester matrix to obtain branched structure, menwhile, it was also take a claim to processing technique.4. Silicon had improved the mechanical properties such as pencil hardness and scratch resistance of polyester coatings, whose scratch resistance weight was even to 1200kg, prepared via ISF and ISP.5. Compared to the method of sol-polyester blending, the synthesis method of ISF and ISP was more convenient, the particar in the matrix was smaller, dispersity and compatibility were also much better and so were the performances of products. TEOS had remakable catalytic activity in the matrix polyester system prepared via ISF and also ISP which could shorten the period of preparation and reduce the cost. Compared with the method of sol-polyester blending, better compatibility between the particar and matrix polyester, more even of films could be obtained via ISF and ISP.6. On the aspect of technics, sol-polyester blending is more convenient to prepare hybrid polyester than ISF and ISP, because gel will be formed more easily in the process of ISF and ISP. On the aspect of apprearance of, resins prepared via ISF and ISP were more uniform and mre transparent, meanwhile, resins via sol-polyester blengding with bad compatability were not so uniform and transparent.and so are the coatings.On the aspects of performances of coatings, such as scratch resietance, hardness etc., the coatings prepared via ISF and ISP were better than samples via sol-polyester blending.compare with ISF, the hybrid polyester was mor steady, and the colour was more bright7. As a conclusion, ISF and ISP ,eapecially the ISP, have important industrial value to enhance the scratch resistance and keep transmission property of polyester/silicon organic-inorganic hybrid coating materials.