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Titolo:
Monitoring polyolefin modification along the axis of a twin-screw extruder. II. Maleic anhydride grafting
Autore:
Machado, AV; van Duin, M; Covas, JA;
Indirizzi:
Univ Minho, Dept Polymer Engn, P-4800 Guimaraes, Portugal Univ Minho Guimaraes Portugal P-4800 er Engn, P-4800 Guimaraes, Portugal DSM Res, NL-6160 MD Geleen, Netherlands DSM Res Geleen Netherlands NL-6160 MD es, NL-6160 MD Geleen, Netherlands
Titolo Testata:
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
fascicolo: 21, volume: 38, anno: 2000,
pagine: 3919 - 3932
SICI:
0887-624X(20001101)38:21<3919:MPMATA>2.0.ZU;2-9
Fonte:
ISI
Lingua:
ENG
Soggetto:
REACTIVE EXTRUSION; MALEATED POLYOLEFINS; INDUCED DEGRADATION; MOLECULAR-STRUCTURE; EPDM RUBBER; POLYPROPYLENE; MELT; FUNCTIONALIZATION; COPOLYMER;
Keywords:
reactive processing; modification; maleic anhydride; rheology;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
32
Recensione:
Indirizzi per estratti:
Indirizzo: Covas, JA Univ Minho, Dept Polymer Engn, P-4800 Guimaraes, Portugal Univ Minho Guimaraes Portugal P-4800 -4800 Guimaraes, Portugal
Citazione:
A.V. Machado et al., "Monitoring polyolefin modification along the axis of a twin-screw extruder. II. Maleic anhydride grafting", J POL SC PC, 38(21), 2000, pp. 3919-3932

Abstract

The physico-chemical phenomena developing along the screw axis of a twin-screw extruder during the grafting of maleic anhydride (MA) onto polyolefins[polyethylene (PE), ethylene-propylene rubber (EPM), and polypropylene (PP)] were investigated. For this purpose, sampling devices located along the extruder barrel were used to collect polymer samples that were subsequentlycharacterized to follow the degrees of grafting and crosslinking or degradation. A similar evolution of MA grafting was observed regardless of the polyolefin type or MA and peroxide concentration when grafting was performed under identical conditions, that is, the same peroxide type and set temperature. A correlation between the MA grafting and the calculated peroxide decomposition was established. Chemical reactions occurred along the extruder axis until the peroxide was fully converted. More detailed quantitative measurements of the peroxide decomposition and MA grafting would allow the development of accurate process models. The final MA content depended on the polyolefin composition (PE > EPM much greater than PP). As expected for PE, crosslinking occurred in addition to grafting, but after a certain residence time, the PE network degraded. The PP viscosity reduction after MA grafting was due to the conversion of tertiary PP radicals into primary PP radicals after grafting. (C) 2000 John Wiley & Sons, Inc.

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Documento generato il 15/07/20 alle ore 21:19:37