Platinum-catalyzed reactions between Si–H groups as a new method for cross-linking of silicones

Abstract

The platinum-catalyzed self-cross-linking of polymethylhydrosiloxane at RT in air was performed for the first time and proved by ¹H, ¹³C, and ²⁹Si SSNMR and swelling measurements. Quantum chemical modeling of possible structures was investigated. Platinum (0) and (II) complexes were used as catalysts between the Si–H groups of polymethylhydrosiloxane. Karstedt's catalyst leads to Si–O–Si and Si–Si bond formation, but cis-[PtCl₂(BnCN)₂] generates predominantly Si–O–Si cross-links. cis-[PtCl₂(BnCN)₂] allows creating high-quality silicone rubbers without visible mechanical defects. This cross-linking approach can be used to obtain new Si–H-containing silicone materials.