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Titolo:
EFFECT OF TACTICITY ON THERMAL-DEGRADATION OF POLY(VINYL CHLORIDE)
Autore:
TROITSKII BB; YAKHNOV AS; NOVIKOVA MA; GANYUKHINA TG; DENISOVA VN;
Indirizzi:
RUSSIAN ACAD SCI,RAZUVAEV INST ORGANOMET CHEM NIZHNII NOVGOROD RUSSIA
Titolo Testata:
European Polymer Journal
fascicolo: 4, volume: 33, anno: 1997,
pagine: 505 - 511
SICI:
0014-3057(1997)33:4<505:EOTOTO>2.0.ZU;2-J
Fonte:
ISI
Lingua:
ENG
Soggetto:
POLYVINYL-CHLORIDE; BRANCH STRUCTURES; INITIAL-STAGE; POLYVINYL-CHLORIDE); DEHYDROCHLORINATION; MACROMOLECULES; MECHANISM; STABILITY; PVC;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
29
Recensione:
Indirizzi per estratti:
Citazione:
B.B. Troitskii et al., "EFFECT OF TACTICITY ON THERMAL-DEGRADATION OF POLY(VINYL CHLORIDE)", European Polymer Journal, 33(4), 1997, pp. 505-511

Abstract

The tacticity of different samples of PVC suspension has been measured by C-13 NMR spectroscopy. The dehydrochlorination of PVC samples under vacuum with continuous removal of HCl by freezing has been studied at 200 degrees. The values of the effective constants-of dehydrochlorination rates of unstable fragments and normal units of PVC, the valuesof the initial and the stationary rates of degradation and the total concentrations of unstable groups in PVC samples have been obtained. It has been shown that only the contents of isotactic nonads may be compared with the values of the concentrations of unstable fragments in the samples. There is no correlation between the initial rate of PVC degradation and the content of isotactic triads or nonads. A correlationexists between the total concentration of unstable fragments and the initial rate of degradation of PVC samples. The obtained results give evidence that the tacticity of macromolecules has no significant influence on the initial stage of the thermal degradation of PVC and that the branching groups with the chlorine atom near the tertiary carbon atom and the internal chloroallylic fragments may be the main unstable groups of PVC macromolecules. (C) 1997 Elsevier Science Ltd.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 14/07/20 alle ore 09:28:42