ISSN:
1022-1352
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Physik
Notizen:
The depolymerization of a triazeno-group containing photopolymer, poly[oxy-1,4-phenyleneazo(methylimino)hexamethylene(methylimino)azo-1,4-phenylene], is investigated in a tetrahydrofuran (THF) solution. Irradiation of the material leads to a clean decomposition of the photolabile polymer, as monitored by UV spectroscopy and gel-permeation chromatography (GPC). As compared to the photolysis in THF solution, the light-induced decomposition rate of a polymer in a polymer film is shown to be much slower. The highly photosensitive triazeno group also decomposes thermally at temperatures above approx. 220°C. The kinetics of thermal degradation of the polymer in substance was investigated at a temperature of 256°C, and monitored by GPC measurements. During this decomposition, one first observes the development of higher molar-mass fractions, which result from grafting reactions of primary radicals. Upon further thermolysis the triazene polymer is completely degraded to low-molar-mass products. The volatile decomposition products were identified by gas chromatography/mass spectrometry (GC/MS) analysis. The protolytic decomposition, which represents the retrosynthesis of the triazene polymer, was studied in a 9:1 mixture of tetrahydrofuran and an aqueous citrate buffer solution. Although the decomposition rate in this solvent mixture is slow, as compared to the depolymerization in diluted hydrochloric acid, a clean decomposition of the triazene polymer is obtained.
Zusätzliches Material:
11 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/macp.1995.021960306
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