Preparation Of Novel Karstedt Catalyst And Its Application In Hydrosilylation

Organic silicon materials get advantages over environmental friendliness, high insulation, low surface tension because of its unique structure. Therefore, they have been widely applied in electronic packaging, personal care products, construction and many other fields. Hydrosilylation is an important measure of obtaining silicon carbide type material. Generally Speier catalyst is used in hydrosilylation in industry. However the system of multi-catalyst is not efficient and the color in some catalytic product is too dark. So, it is necessary to develop a novel platinum complex catalyst.In this paper, Two types of Karstedt catalysts, Pt-allylic polyether complexes(Pt-APE) catalyst and Pt-vinyl-ended ploydimethylsiloxane complexes(Pt-Vi-PDMS) were synthesized.The vinyl-ended ploydimethylsiloxane(Vi-PDMS) was prepared in a two-step method of synthetic process. Then the Pt-APE catalyst was applied in the synthesis of polyether modified silicone oil. The performance of Pt-APE catalyst was tested by the Si-H conversion rate, product appearance and product color. The Pt-Vi-PDMS catalyst was used in the synthesis of silicone rubber and its performance was measured by hardnesss and light transmittance.In the first part, Pt-APE catalyst was prepared with allyl polyether(APE), H2PtCl6 and isopropyl alcohol. The influences of coordination temperature, time and the mass ratio of Pt and APE were discussed. In the synthesis of silicone oil modified by polyether, the factors of reaction temperature, time and the amount of Pt-APE catalyst were optimized. It was found that the optimum silicone oil looked approximate colorless and transparent, while the Si-H conversion rate was 95.18% and chroma was 23 Hazen. Compared with the traditional Speier catalyst, the dosage of the catalyst was less to get the same conversion rate and the color of the product was light-colored.In the second part, the vinyl-ended ploydimethylsiloxane(Vi-PDMS) was synthesized by two step process(hydrolysis condensation and condensation). Dimethyldiethoxylsilane was used as raw materials, the effects of temperature, n(H2O):n((CH3)2Si(OC2H5)2) and the dosage of catalyst HCl were discussed. Secondly, the conditions of condensation process were optimized. At last, the characteristics of vinyl-ended ploydimethylsiloxane were analyzed by FT-IR and 1H-NMR.In the third part, H2 Pt Cl6, Vi-PDMS and isopropyl alcohol were used as raw materials, the catalyst Pt-Vi-PDMS was obtained. In the curing of silicone rubber, it was found that the low viscosity catalyst had a better performance. Compared with Speier catalyst, its performance was improved greatly. When the dosage of catalyst Pt-Vi-PDMS was 8ppm, the light transmittance of curing product was 93.67%, and the hardness was 73 shore.