The mechanical and thermal properties of the solution-cast films of chemically prepared polyaniline have been studied by means of dynamic mechanical analysis (d.m.a.), differential scanning calorimetry (d.s.c.) and thermogravimetric analysis (t.g.a.). The glass transition temperature (Tg) of the polyaniline films in emeraldine base form was determined and characterized for the first time to be in the range of 105–220°C for the films containing16-0% of 1-methyl-2-pyrrolidinone (NMP) residual solvent, respectively. A critical parameter for a shape memory polymer lies in its shape memory transition temperature. For an amorphous SMP polymer, it is highly desirable to develop methods to tailor its Tg, which corresponds to its shape memory transition temperature. Starting with an amine cured aromatic epoxy system, epoxy polymer were synthesized by either reducing the crosslink density or introducing flexible aliphatic epoxy chains. The thermaland thermomechanical properties of these epoxy polymers were characterized by differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). All the crosslinked epoxy polymers with Tg's above room temperature were found to possess shape memory properties. Overall, our approach represents a facile method to precisely tune the Tg of epoxy SMP polymers ranging from room temperature to 89 °C.
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