| Popis: |
The morphology of dry-jet wet-spun fibers of rigid rod polymers is currently understood on the basis of extensive microscopic studies, but the structure formation mechanism is not understood equally well. An approach is outlined here according to which the elementary microfibrils and microvoids result from a clustering mode that is related to spinodal decomposition, and proceeds through a concentrational and orientational rearrangement of the macromolecular rods within a transient network. Simple relations connecting the rigid rod content of the spinning dope and the characteristic dimensions of the microfibrils and the microvoids are proposed. In the case of composite fibers of rigid rod polymers with the phthalocyanine (Pc) compounds NiPc (crystalline) or (SiPcO)n (short rigid rod polymer), the rigid rod matrix hosts the Pc phase in axially elongated pockets that are geometrically similar to the microvoids and exist at different size scales. A process capable of yielding rigid rod domains and pockets at different size scales is described. Journal of Macromolecular Science, Part B: Physics |
