Relaxation transitions in segmented polyether polyurethaneureas studied by thermally stimulated current analysis

Relaxation behavior of poly(ethylene glycol)-type segmented polyether polyurethaneurea (PEUU), which has microphase separated structure formed by hard and soft segments, was studied by TSC technique. TSC spectra of the PEUU films obtained by casting a N,N-dimethylacetamide solution of the PEUU showed four peaks which are denoted γ,β,α, and ρ, in order of increasing temperature. These peaks are found to be closely related to molecular motion of the soft segment, namely, local motion (γ peak) of oxyethylene sequence, glass transition (β peak) caused by micro-Brownian motion, Maxwell-Wagner-Sillars interfacial polarization (α peak), and transport (ρ peak) of charged ionic species. These experimental results demonstrated that the TSC analysis is a valuable tool for studying host polymer of polymeric solid-state ionic conductors