Conformation and dynamics of polymer chains in condensed systems

摘要

AbstractA Stockmayer's type‐A chain such as cis‐polyisoprene (PI) having dipole components parallel to the chain contour exhibits slow dielectric response, reflecting fluctuation of its end‐to‐end vector (dielectric normal modes). This article reviews our own work on dielectric spectroscopy for studying dynamics and conformational properties of probe PI chains in binary blends with PI or polybutadiene (PB) that does not exhibit normal modes. Through such studies we were able to see the crossover of the probe‐chain dynamics fromRousebehaviour in low‐molecular‐weight (lmw) matrices topure reptationbehaviour in high‐molecular‐weight (hmw) matrices. We were also able to confirm experimentally Flory's earlier prediction on excluded volumes in dilute blends ofhmwprobe chains inlmwmatrices, for which a proof has never