Homopolymers and interpenetrating networks based on diethylene glycol-his-allyl carbonate and methyl methacrylate were prepared using free radical initiators and their dynamic mechanical properties were investigated. The changes of glass transition temperature and tan delta(max) with conversion are reported. This data is used to estimate the changes in the mobility of the system with conversion. The effect of the change in composition in copolymers on tan delta peak width, tan delta(max) and area under the tan delta curve are used to understand the network distribution, miscibility and damping properties.