Exploring self-polymerization technique for fabrication of high viscosity polydimethylsiloxane from dichlorodimethylsilane without using catalyst

Abstract Self-polymerization offers an easy and simple technique to produce polydimethylsiloxane (PDMS) from dichlorodimethylsilane (DCDMS). This method is a condensation stage that does not require additional treatments and materials. Here, we report the self-polymerization technique for the synthesis of high-viscosity PDMS without using a catalyst. Synthesis was carried out using dichloromethane (DCM) solvent with the volume ratio to DCDMS was 1:1. The polymerization process lasted for 63 days. PDMS with a viscosity of 5.13 Pa s which meets the category of high-viscosity of vitreous substitution obtained. The sample was clear and had a refractive index of 1.4028, slightly lower than commercial PDMS. The surface tension of the sample was 21 milliN/m. The sample has the advantage of higher surface tension compared to the commercial PDMS. It will have the effect of reducing the emulsification tendency. The viscosity, refractive index, and surface tension of the sample meet the requirements for the application of a vitreous humour substitute. This research reduced the number of catalyst and solvent used in the hydrolysis and accelerated the polymerization process.