Viscoelastic relaxations in poly(dimethylphenyl methacrylates)

Dynamic mechanical properties of poly(dimethylphenyl methacrylátes) were studied considering the different positions of the methyl groups on the phenyl ring. In all cases a clear α relaxation can be observed which is associated to the polymer glass transition temperature (Tg). Nevertheless, at lower temperatures, viscoelastic activity is negligible. A correlation between the steric hindrance due to the methyl groups and the temperature at which the relaxation is detected, was established.