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Titolo:
SIZE-EXCLUSION CHROMATOGRAPHIC MEASUREMENT OF PVC MOLECULAR-WEIGHT DISTRIBUTIONS
Autore:
PANG S; RUDIN A;
Indirizzi:
UNIV WATERLOO,DEPT CHEM,INST POLYMER RES WATERLOO N2L 3G1 ONTARIO CANADA UNIV WATERLOO,DEPT CHEM,INST POLYMER RES WATERLOO N2L 3G1 ONTARIO CANADA
Titolo Testata:
Journal of applied polymer science
fascicolo: 7, volume: 49, anno: 1993,
pagine: 1189 - 1196
SICI:
0021-8995(1993)49:7<1189:SCMOPM>2.0.ZU;2-O
Fonte:
ISI
Lingua:
ENG
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
14
Recensione:
Indirizzi per estratti:
Citazione:
S. Pang e A. Rudin, "SIZE-EXCLUSION CHROMATOGRAPHIC MEASUREMENT OF PVC MOLECULAR-WEIGHT DISTRIBUTIONS", Journal of applied polymer science, 49(7), 1993, pp. 1189-1196

Abstract

Aggregates that may exist in poly (vinyl chloride) (PVC) solutions atambient temperatures compromise the accuracy of SEC measurements of molecular weight distributions. Aggregate-free solutions can be produced in 1,2,4-trichlorobenzene (TCB) by controlling the dissolution time and temperature. SEC measurements were made in trichlorobenzene at 110-degrees-C after dissolution for 12 h at 120-degrees-C. An on-line continuous viscometer can be used to determine when aggregate-free solutions have been produced. The Mark-Houwink parameters (K = 0. 161 mL / g, alpha = 0. 762) can be used for universal calibration procedures in TCB at 110-degrees-C. Complete dissolution of the PVC affects the highmolecular weight end of the molecular weight distribution. Measured M(n)BAR values are not affected, but M(z)'s are much higher than those estimated, for example, from room-temperature SEC analyses in tetrahydrofuran. Molecular weight distributions are also seen to be broader, especially for higher molecular weight PVCs. (C) 1993 John Wiley & Sons, Inc.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 26/11/20 alle ore 20:22:53