Molecular dynamics of poly(2-(2-methoxyethoxy)ethyl methacrylate) hydrogels studied by broadband dielectric spectroscopy

The molecular dynamics of poly(2-(2-methoxyethoxy)ethyl methacrylate), PMEO2MA, hydrogels with varying water contents were studied using broadband dielectric spectroscopy. Based on the water content, the PMEO2MA hydrogels were divided into two groups: (i) low water content systems (SD ? 0.5) with molecular dynamics dominated by polymer local and segmental movements and (ii) high water content systems (SD > 0.5) with molecular dynamics prevailing in water. In low water content systems, four molecular processes slightly affected by water were found. Two of the processes above Tg arise from segmental motions, while two processes observed below Tg relate to local motions of PMEO2MA. The water dynamics in high water content systems vary depending on the swelling degree and significantly differ from the molecular dynamics of pure water.