Hyperbranched poly(siloxysilane) and its UV curing kinetics

UV-curable hyperbranched poly(siloxysilane) was synthesized via organosilicon polymer bearing silicon hydride end groups and vinyltriallylsilane at the presence of Pt/C catalyst. FT-IR, ¹H-NMR, ¹³C-NMR, ²⁹Si-NMR and SEC/MALLS were employed to identify the structure of the polymer. UV curing experiments were conducted at different temperature, light intensity and atmosphere through UV-DSC. The relations of heating flow and conversion versus time at different temperature, light intensity and atmosphere were studied. The results reveal that the acceleration of light intensity to curing reaction is selective to temperature, and the termination of polymerization by oxygen is not remarkable at room temperature or below. The kinetic parameters were obtained by curvefitting of the experimental data with experiential formula (which is operated in software Matlab7.1). Compared with the experimental curves, the theoretic model showed well accordance. Curing active energy E_a and frequency gene A were obtained by plot of lnk versus -1/RT.