Research On Environment-protective Automotive Surface Polish

Automotive surface polish is a kind of fine chemical product which keeps the carbody neat, bright and prevents the surface coating aging by forming a protective coating. On the basis of investigation on domestic and overseas study, an original automotive polish based on methyl-long-chain alkylsiloxane was prepared.The synthesis of methyl-long-chain alkylsiloxane was performed by hydrosilyation reaction usingα-olefin and hydrodilstion KF99 as raw materials and chloroplatinic acid-isopropanol as catalyst. By the single factor method, the influences of various factors such as the mass ratio of the raw materials, the reaction temperature, the reaction time, the amount of catalyst and the time of dropping KF99 on methyl-long-chain alkylsiloxane were studied. Accordingly the optimum reaction condition to synthesize methyl-long-chain alkylsiloxane is as follows: the mass ratio of the raw materials is KF99:α-olefin =21:22, the reaction temperature is 130°C, the reaction time is 13 hours, the amount of catalyst used is 0.0082 wt.% of the raw materials and KF99 is added dropwise within 60 minutes. The structure of the reaction materials, products and the hydrosilyation reaction was analyzed via ~1H-NMR and FT-IR. The reaction mechanism has been discussed primarily.A new kind of liquid automotive polish was prepared by selecting various raw materials and applying methyl-long-chain alkylsiloxane in it, and the properties such as brightness, pH value, temperature stability, corrosion resistance and defoaming ability were tested. The results showed that its properties could reach the same level of the similar domestic and overseas products and the methyl-long-chain alkylsiloxane could substitute for the traditional siloxane in automotive surface polish.