초록 |
Polymers composed of polycyclic aromatic planar diimide (PCAD) units and flexible rubbery poly(propylene glycol) (PPG) chains were synthesized, and the viscoelasticity and morphology were investigated. The polymers were synthesized by polycondensation of naphthalene or perylene tetracarboxylic dianhydrides with PPG-diamines and subsequent thermal imidization. The thermal and viscoelastic properties were measured by DSC and dynamic mechanical analysis, respectively. The molecular aggregation structure was investigated by FT-IR, wide-angle XRD and small-angle X-ray scattering measurements. The viscoelastic characteristics and morphology depend on the PCAD structure and molecular weight of the PPG segments, and the polymers composed of perylene diimide units and high molecular weight PPG chains show rubber elasticity because of the well-segregated morphology. The thermal stability was enhanced by PPG chain end capping by thermally stable PCAD units. |