Synthesis and characterization of UV-curable poly(dimethylsiloxane) dimethacrylate

This paper presents a new route to the synthesis of UV-curable poly(dimethylsiloxane) dimethacrylate (PDMSDMA). PDMSDMA was essentially prepared by modification of poly(dimethylsiloxane), bis(3-aminopropyl) terminated (PDMS-NH2) with methacrylic anhydride (MAA). The synthesized products were cured under UV in the presence of camphorquinone (CQ) used as a photoinitiator. The chemical structure of PDMSDMA samples was analyzed by FT-IR and H-1-NMR spectroscopy. The H-1-NMR spectrum of PDMSDMA revealed new peaks at 3.20 ppm, corresponding to methylene protons in -CH2-NH-, and 5.25 and 5.65 ppm, corresponding to vinylic protons in -NH-CO-CCH3=CH2. The chemical structure of the cured products and the degree of curing were determined by solid state C-13 Cp/MAS NMR and FT-IR (micro-ATR) spectroscopy. Various parameters, such as concentration of methacrylic anhydride, amount of camphorquinone, and curing time, were studied.