Mechanical properties of copolymers from methacrylate functionalized silanes and bifunctional methacrylate monomers

Sol gel derived composite materials were prepared from methacryloxypropyltrimethoxysilane (MPTS) and tetraethyleneoxidedimethacrylate (TEGDMA). The amount of MPTS in the composites was varied from 0 to 50 mole%. MPTS was prehydrolyzed at room temperature with 0,1 mole/1 HCl/H2O. After complete removal of solvent calculated amounts of TEGDMA were added to the reaction mixture of the prehydrolyzed MPTS. Thermically initiated free radical copolymerization of the methacrylate endgroups was performed in the resulting mixture under nitrogen atmosphere using azobisisobutyronitril (AIBN) as initiator. The composites were investigated by high resolution transmission electronmicroscopy in order to investigate the morphology. The thermomechanical properties as storage, loss modulus, tan - as well as the glass transition temperature (T-g) of the composites were estimated by dynamic mechanical thermal analysis (DMTA).