ISSN:
0449-296X
Schlagwort(e):
Physics
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
The synthesis and cyclocopolymerization with sulfur dioxide of four 1,5- and 1,6-dienes (bicyclopentene, bicyclohexene, dicyclopentenyl ether, and dicyclohexenyl ether) and one tetraene (quartercyclopentene) is described. Under optimum conditions, completely soluble copolymers are obtained from bicyclopentene in high conversions at temperatures down to -39°C. Bicyclohexene also gave soluble copolymers, but in a by far slower reaction and in low conversion. Quartercyclopentene does copolymerize, but as expected, gives only insoluble polymers. The two compounds with 1,6-diallyl ether structure, dicyclopentenyl ether and dicyclohexenyl ether, failed to polymerize. The influence of initiator, temperature, reaction medium, diene concentration, etc., on the properties of the polymers was studied in detail for copolymerizations of bicyclopentene. Only a very limited number of peroxides in unusual large quantities was found to be effective in initiating this copolymerization. The reaction is further limited to a narrow choice of solvents, e.g,. diethyl ether and tetrahydrofuran, in order to obtain soluble products. Polymerization could not be achieved in ethanol, benzene, methylene chloride, dimethyl sulfoxide, and tetramethylene sulfone; excess sulfur dioxide yields only dark and insoluble products. Diene concentrations of below 0.3 wt.-% are normally required to obtain poly(bicyclopentene sulfones) which are soluble in dimethyl sulfoxide, tetramethylene sulfone, or sulfuric acid. Polymerization can be carried out from room temperatures down to -39°C.; optimum results are generally obtained around 0°C. Inherent viscosities of 1.72 (0.5 g./100 ml. dimethyl sulfoxide) have been measured. X-ray diffractions are those of amorphous polymers.
Zusätzliches Material:
7 Tab.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/pol.1967.150050802
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