Photopolymerization kinetics and dynamic mechanical properties of silanes hydrolysed without evolution of byproducts. Tetrakis(methacryloyloxyethoxy)silane - diethylene glycol dimethacrylate.

C. UYGUN; W. COOK; C. MOORHOFF; F. CHEN; C. VALLO; Y. YAGCI; M. SANGERMANO

MACROMOLECULES

AMER CHEMICAL SOC

Lugar: New York; Año: 2011 vol. 44 p. 1792 - 1800

0024-9297

The temperature dependence of photopolymerization kinetics of tetrakis(methacryloyloxy-ethoxy)silane (TetMESi) was compared with an analogue, diethylene glycol dimethacrylate and their copolymers.  In all cases the kinetics are controlled by the temperature dependence of the propagation step, the effect of diffusion on radical termination, the effect of rising glass transition during cure and topological restraint on complete conversion.  The glass transition region of these polymers were very broad, suggesting their use in high temperature applications.  NMR, FTIR and water sorption measurements of the TetMESi-based polymers during exposure to water showed that the Si-O-C bond was slowly hydrolysed resulting in water swollen polymers containing poly(hydroxyl ethyl methacrylate) which reduced the glass transition temperature and narrowed the glass transition region.  UV-vis spectroscopic studies showed that during exposure to water, nano-SiO2 particles were formed from the condensation of the siloanol groups formed during the hydrolysis of TetMESi.