Verification of the changes in the structural and physical properties of PU/PEO embedded with graphene oxide

Blend of polyurethane (PU) and polyethylene oxide (PEO) doped graphene oxide (GO) was prepared and investigated. The main bands of GO were increased with increasing of graphene contents due to oxidant induced chemical attachment of PU/PEO chains to the surface of GO. IR bands were increased attributed to oxidant-induced chemical attachment between GO and PU/PEO chains. The shift in TGA curves toward higher temperatures than that of PU/PEO which indicate the thermal stability of the samples. The activation energy was increased implying a variation of reactivity as a result of the extent reaction. Moreover, the kinetic parameters ΔS, ΔH and ΔG indicate that the addition of GO cause increase of thermal motion and decrease of the thermal stability. On the other hand, the behavior of ε′ and ε″ curves was decreased at low frequency and become nearly constant at the higher frequency due to the relaxation time. At low frequencies, the electric dipoles have enough time to align with field however at high frequencies attributed to shorter time available for dipoles to align after a rise of the field. A rise for M′ and M″ at the range of higher frequencies due to bulk effect suggesting polarity of relaxation mechanism.