Static and dynamic light scattering from p-conjugated poly(4BCMU) in toluene solutions were measured at 353 K (yellow phase) and 323 K (red phase) to evaluate the hydrodynamic radius Rh and the fractal dimension D. It was suggested that poly(4BCMU) may exist not as an isolated worm-like chain but as a weakly interacted cluster-like domain in the yellow phase. The domain was considered to be elaborated by inter-molecular hydrogen bondings formed newly through a thermal break of intra-molecular hydrogen bondings between side chains along a main chain. On the other hand, the increases in Rh and D have revealed that poly(4BCMU) chains aggregated gradually in the red phase, after taking a single extended rod-like conformation. The subsequent aggregation seemed to be promoted not only by lowering a solvent quality but also by increasing the effective concentration, accompanied by the conformational transition.
Посилання на статтю:
Chromatic transition of p-conjugated polydiacetylene and the subsequent aggregation phenomena / Hidetoshi Oikawa, Tatsumi Korenaga, Shuji Okada, Hachiro Nakanishi // Polymer. – 1999. – N 40. – P. 5993–6001.