Synthesis of a Novel Platinum Catalyst and Its Application in the Photoactivated Hydrosilylation Reaction

Abstract

Photocatalyzed hydrosilication has the advantages of high reaction efficiency and environmental friendliness. However, the cost of photosensitive platinum catalysts is very high, hindering their applications. In this work, a novel and cost-effective photosensitive platinum catalyst is synthesized and can effectively catalyze the hydrosilylation reaction under ultraviolet light. It is found that Pt catalysts exhibit catalytic activity under ultraviolet light when the ratio of Platinum chloride bonding and cyclopentadienyl (Pt-Cl:Cp) is higher than 1:1.2. The cost is reduced by 50%. The structure of this platinum catalyst is characterized using FTIR and NMR techniques. Under ultraviolet light, the new photosensitive platinum catalyst’s catalytic efficiency increases from approximately 5% to 60%. The viscosity of prepared silicone rubber was measured. Results show that the prepared silicone rubber has a storing time of over 30 days in shaded environments, and can be completely cured within 2 min under ultraviolet light. The thermal decomposition residual mass of photocured silicone rubber products is as high as 70%, having good thermal stability. As the content of the platinum catalyst increases from 20 to 100 ppm, the reaction conversion rate of the hydrosilylation reaction increases from 43 to 60%. The hardness of the silicone rubber also increases from the initial 11 degrees to 20 degrees. This novel photosensitive platinum catalyst has potential applications in 3D printing and electronic packaging.