Synthesis of Polydimethylsiloxane and its Monomer from Hydrolysis of Dichlorodimethylsilane

Abstract

Polydimethylsiloxane (PDMS) is a tamponade substance that is used as vitreous humour substitutes in vitreoretinal surgery. PDMS can be obtained from monomers of Octamethylcyclotetrasiloxane (D4) that was reacted with Hexamethyldisiloxane through polymerization reactions in a base condition. The monomers are very difficult to obtain in Indonesia, therefore another alternative monomer is needed to produce PDMS with specific properties for vitreoretinal surgery. Here, we reported the synthesis of monomer for replacing D4 through hydrolysis process of Dichlorodimethylsilane (DCMS). Furthermore, the synthesized monomer was used to produce PDMS. The process of DCMS hydrolysis assisted by KOH 0.5 M along 18 hours in reflux system. The synthesized monomer has viscosity of 171 mPas, refractive index of 1.4005 and surface tension of 17 mN/m. PDMS was produced using synthesized monomer by ring-opening polymerization. It is found that the properties of PDMS are very similar with that of commercial PDMS of 5500 cSt.