Synthesis of ultra-high molecular weight poly(methyl methacrylate) with hydrosilane as initiator

Hydrosilanes, including diethylsilane (DES), triethylsilane (TES), phenylsilane (PSH), and diphenylsilane (DPS), have in the present study been used as initiators for the preparation of poly(methyl methacrylate) (PMMA) in the presence of Pd nanoparticles (Pd NPs). DPS initiated the polymerization of MMA in the production of PMMA, with a number average molecular weight ( M n ) of 2.00 × 10 6 Da and a dispersity (PDI) of 1.81 in the presence of 18.9 ppm of Pd NPs. The kinetic of the polymerization was investigated and the reaction orders, with regard to the MMA, DPS, and Pd NPs, were calculated as 0.85, 0.58, and 0.80, respectively. The molecular weight of the PMMA was measured using gel permeation chromatography (GPC) and the structure was characterized using proton nuclear magnetic resonance ( 1 H NMR). The transmission electron microscopy (TEM) and electron spin resonance (ESR) results revealed that the polymerization took place at the surface of the Pd NPs through a radical mechanism.