New Long-chain Catalytic Synthesis Of The Silane Coupling Agent

Organosilicon materials are widely used in aerospace, electrical and electronic, textile, light industry, building, machinery, medical, food, transportation and other industrial sectors. Hydrosilylation is one of the most important methods to prepare the silane coupling agents. At present, the widely used catalytic system in industry is the platinum complexes. However, there are two major disadvantages. Firstly, the catalysts are very expensive and not easy to recycle. Secondly, in the case of olefins with electronic-drawing substituents, conventional platinum catalysts are not effective. In this paper, we synthesize several types of palladium catalysts and tin catalysts and apply them to hydrosilylation reaction. The results are as follows:1. Homogeneous and heterogeneous platinum catalysts were prepared. "Speier" catalysits with different solvents and Karstedt catalysts using chloroplatinc acid, divinyl tetramethyl siloxane, ethanol, sodium bicarbonate as reactants were synthesized. We prepared carbon supported liquid-phase platinum catalyst. The acticity of these catalysts for the hydrosilation of 1-octene with triethoxysilane were measured.2. Dodecyltrimethoxysilane was synthesized by the reaction of 1-dodecene with trimethoxysilane using Pt-catalysis, and the structure of the product was characterized. The effects of the type and amount of catalysts, reaction temperature, and reaction time were discussed. The most reasonable amount of catalyst is 50ppm. Yield of the addition product is highest (82.75%) under the temperature 60～70℃and the reaction time being 4h.3. Under the catalyzation of platinum complexes, a linear alkyl coupling agent named dodecyldiethoxymethyl-silane was synthesized using 1-dodecene and methyldiethoxysilane, and the structure of the product was characterized. The effects of the type and amount of catalysts, reaction temperature, and reaction time were discussed. The most reasonable amount of catalyst is 40ppm. Yield of the addition product is highest (82.45%) under the conditions of temperature being 75～80℃and the reaction time being 4h.4. Under the catalyzation of platinum complexes, a linear alkyl coupling agent named hexadecylmethyldiethoxysilane was synthesized using 1-hexadecene and methyldiethoxysilane, the structure of the product was characterized. The effects of the type and amount of catalysts, reaction temperature and reaction time were discussed. The results demonstrated that the most reasonable amount of catalyst is 40ppm, the product yield 80%, when the temperature was between 80～90℃, the time of reaction was 4h.5. 2-(3,4-Epoxycyclohexyl)ethyl triethoxysilane were synthesized by the platinum complexes catalyzed hydrosilation reaction of triethoxysilane and 1, 2-epoxy-4-vinylcyclohexane. The structure of the product was characterized. The effects of the type and amount of catalysts, reaction temperature, and the amount of solvent on the production rate were discussed. The results demonstrated that the most reasonable amount of catalyst is 40ppm, the product yield 80%, when the temperaturewas between 80～90℃, the ratio of solvent and EVCX was 0.4:1.6.β-alkoxycarbonylethyltin dichloride xanthonates were synthesized and applied to the addition reaction of 1-octene and trimethoxysilane. The study found that the catalytic activity of two tin complexes is less than that of the classic "Speier catalyst" and in this addition reaction, adding THF "Speier catalyst" can get the best catalytic effect.It is found that hydrosilylation reactions can carry out at low amount of platinum catalyst in short time. This type of catalysts have high catalytic activity, the performance of the catalysts was evaluated by synthesis of several important silanes. The preparation technology for linear alkyl coupling agents was studied using this catalyst. This platinum catalysts have high catalytic activity, selectivity high stabilization, and low catalyst usage characteristics. The process produces low levels of byproducts and can provides a higher yield per unit volume of equipment. The results indicate that we synthesized platinum complexes are simple and suitable for extensive industrialization produce.