ISSN:
0025-116X
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Physik
Notizen:
Theoretical calculations have shown that it should be possible to determine the molar mass of the grafted chains of graft copolymers by light scattering measurements in suitable mixed solvents, and moreover, that this should be possible without the backbone having to be degraded, without the ungrafted backbone having to be isolated, and without the refractive index increment having to be determined after dialysis. Among the conditions that have to be met are the requirements that the mixed solvent must be isorefractive with respect to the backbone and that the preferential solvation of the grafted chains must be independent of their molar mass. The method is applied to fractions of graft copolymers with styrene or styreneacrylonitrile (SAN) being grafted onto ethylene/vinyl acetate copolymers, from which ungrafted polystyrene or SAN copolymer has been removed by solvent demixing. With this method the molar mass and the number of grafted chains, the coupling of backbone molecules via grafted chains, the shrinking and segregation of the individual grafted chains and the incompatibility of the grafted chains with the backbone polymer can be determined.
Zusätzliches Material:
11 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/macp.1984.021850514