ISSN:
1022-1336
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Physik
Notizen:
The homopolymerization of styrene and its copolymerization with ethylene in the presence of a vanadium-based supported catalyst, {VCI3, 1 AICI3}, associated to triethylaluminium is examined. As indicated by means of 13C nuclear magnetic resoance and differential scanning calorimetry analysis, the homopolystyrenes obtained present a highly isotactic microstructure and are semicrystalline (melting temperature 220°C).In the case of styrene/ethylene random copolymerization, the formation of both, polyethylene blocks and isotactic polystyrene sequences was identified by analysis of the crude polymer. Solubility characteristics and structural characteristics from nuclear magnetic resonance spectra of these products support the formation of copolymers with ethylene and isotactic styrene blocks rather than that of two distinct homopolymers.
Zusätzliches Material:
6 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/marc.1996.030170704
Permalink
