| Popis: |
Light scattering, osmometric and viscometric studies were carried out with dilute solutions of well-defined poly(4,4′-isopropylidenediphenyl carbonate)-block-polystyrene multiblock copolymers, PC-b-PS, in non-selective and selective solvent systems. The influence of copolymer composition, numbers and lengths of blocks in the copolymer chain and type of solvent used on the dilute solution properties, conformation of the investigated multiblock copolymers and on some thermodynamic parameters are discussed. The intrinsic viscosity [η], the unperturbed dimension 〈R02〉/M and the second virial coefficient A2 are larger in non-selective solvents than expected from the averaged values of the parent homopolymers. In benzene, a selective solvent for polystyrene, formation of micelles is possible. |
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