Real-time micro-raman measurements on stressed polyethylene fibers. 1. Strain rate effects and molecular stress redistributionModeling the role of stabilizing additives during melt recycling of high-density polyethylene

Kartalis, CN; Papaspyrides, CD; Pfaendner, R

dc.contributor.author	Tsenoglou, C	en
dc.contributor.author	Kartalis, CN	en
dc.contributor.author	Papaspyrides, CD	en
dc.contributor.author	Pfaendner, R	en
dc.date.accessioned	2014-03-01T01:16:45Z
dc.date.available	2014-03-01T01:16:45Z
dc.date.issued	2001	en
dc.identifier.issn	0021-8995	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/14202
dc.subject	Branching	en
dc.subject	Degradation	en
dc.subject	High-density polyethylene	en
dc.subject	Processing	en
dc.subject	Recycling	en
dc.subject	Restabilization	en
dc.subject	Rheology	en
dc.subject.classification	Polymer Science	en
dc.subject.other	Additives	en
dc.subject.other	Chemical modification	en
dc.subject.other	Crosslinking	en
dc.subject.other	Degradation	en
dc.subject.other	Extrusion	en
dc.subject.other	Macromolecules	en
dc.subject.other	Mathematical models	en
dc.subject.other	Melting	en
dc.subject.other	Pyrolysis	en
dc.subject.other	Recycling	en
dc.subject.other	Rheology	en
dc.subject.other	Stabilizers (agents)	en
dc.subject.other	Thermal effects	en
dc.subject.other	Viscosity	en
dc.subject.other	Melt recycling	en
dc.subject.other	Stabilizing additives	en
dc.subject.other	High density polyethylenes	en
dc.title	Modeling the role of stabilizing additives during melt recycling of high-density polyethylene	en
heal.type	journalArticle	en
heal.identifier.primary	10.1002/app.1324	en
heal.identifier.secondary	http://dx.doi.org/10.1002/app.1324	en
heal.language	English	en
heal.publicationDate	2001	en
heal.abstract	Post-use high-density polyethylene, almost devoid of any stabilizing agents, was restabilized in various degrees and subjected to multiple extrusion cycles at different reprocessing temperatures for assessing its chemical stability. The process-induced material degradation was attributed primarily to long-chain branching caused by crosslinking. It was monitored by an increase in viscosity and evaluated on the basis of an approximate expression derived using fundamental principles of macromolecular rheology. It was determined that long-chain branching increases with temperature and the extent of processing, while decreasing with the amount of restabilizing agent added. A simple model was developed to quantitatively describe the progress of the chemical change by relating it to key material and operational variables. Besides constituting a useful method of monitoring and controlling polymer modification during processing, this model suggests ways of optimizing stabilization according to the particular processing and product requirements. (C) 2001 John Wiley & Sons, Inc.	en
heal.publisher	JOHN WILEY & SONS INC	en
heal.journalName	Journal of Applied Polymer Science	en
dc.identifier.doi	10.1002/app.1324	en
dc.identifier.isi	ISI:000167862400012	en
dc.identifier.volume	80	en
dc.identifier.issue	12	en
dc.identifier.spage	2207	en
dc.identifier.epage	2217	en