Effect of hindered piperidine light stabilizer molecular structure and UV-absorber addition on the oxidation of HDPE. Part 1: Long-term thermal and photo-oxidation studies

2.50
Hdl Handle:
http://hdl.handle.net/2173/108711
Title:
Effect of hindered piperidine light stabilizer molecular structure and UV-absorber addition on the oxidation of HDPE. Part 1: Long-term thermal and photo-oxidation studies
Authors:
Liauw, Chris; Quadir, Angela; Allen, Norman S.; Edge, Michele; Wagner, Alan
Citation:
Journal of vinyl and additive technology, 2004, vol. 10, no. 2, pp. 79-87
Publisher:
John Wiley & Sons
Issue Date:
Jun-2004
URI:
http://hdl.handle.net/2173/108711
DOI:
10.1002/vnl.20011
Additional Links:
http://doi.wiley.com/10.1002/vnl.20011
Abstract:
This series of papers explores the effect of structural characteristics of 2,2,6,6-tetramethylpiperidine-based hindered amine light stabilizers (HALS) on the long-term (40 months) thermal (110°C in air) and photo-stabilization (Microscal unit wavelength >300 nm) performance characteristics of high-density polyethylene formulations. Possible synergism with a triazine functional UV absorber is also explored. Under thermal degradation (measured by carbonyl index) the polymeric HALS performed best, mainly because of reduced volatilization. Additionally, >N-methyl HALS generally showed superior performance under thermal degradation. There was no synergism between an N-CH3 polymeric HALS and the UV1164 triazine additive. However, the equivalent N-H polymeric HALS interacted in a complex manner with UV1164, giving synergism and antagonism, depending on HALS/UV1164 ratio. Strong synergism was evident with the monomeric HALS when the total stabilizer level was 0.2% w/w. Reduction in the overall stabilizer level to 0.05% w/w eliminated the synergism. The UV1164 alone led to rapid and intense yellowing; however, the rate and intensity of yellowing reduced dramatically upon combination with HALS, particularly when the UV1164 level was above 0.1% w/w. When the formulation was under UV attack, the molar mass and the type of N-substitution had no influence on stabilization performance because of the relatively low temperature of testing (leading to reduced volatilization), and the similarly effective UV-stabilization routes for N-methyl HALS and N-H HALS. Under UV attack, yellowing reached a maximum and then decreased to approximately the initial level, while HALS/UV1164 combinations generally showed weak antagonism.
Type:
Article
Language:
en
Description:
Full-text of this article is not available in this e-prints service. This article was originally published [following peer-review] in Journal of Vinyl & Additive Technology, published by and copyright John Wiley and Sons.
Keywords:
Photo-stabilization; Synergism
ISSN:
1083-5601; 1548-0585

Full metadata record

DC FieldValue Language
dc.contributor.authorLiauw, Chrisen
dc.contributor.authorQuadir, Angelaen
dc.contributor.authorAllen, Norman S.en
dc.contributor.authorEdge, Micheleen
dc.contributor.authorWagner, Alanen
dc.date.accessioned2010-07-30T14:53:11Z-
dc.date.available2010-07-30T14:53:11Z-
dc.date.issued2004-06-
dc.identifier.citationJournal of vinyl and additive technology, 2004, vol. 10, no. 2, pp. 79-87en
dc.identifier.issn1083-5601-
dc.identifier.issn1548-0585-
dc.identifier.doi10.1002/vnl.20011-
dc.identifier.urihttp://hdl.handle.net/2173/108711-
dc.descriptionFull-text of this article is not available in this e-prints service. This article was originally published [following peer-review] in Journal of Vinyl & Additive Technology, published by and copyright John Wiley and Sons.en
dc.description.abstractThis series of papers explores the effect of structural characteristics of 2,2,6,6-tetramethylpiperidine-based hindered amine light stabilizers (HALS) on the long-term (40 months) thermal (110°C in air) and photo-stabilization (Microscal unit wavelength >300 nm) performance characteristics of high-density polyethylene formulations. Possible synergism with a triazine functional UV absorber is also explored. Under thermal degradation (measured by carbonyl index) the polymeric HALS performed best, mainly because of reduced volatilization. Additionally, >N-methyl HALS generally showed superior performance under thermal degradation. There was no synergism between an N-CH3 polymeric HALS and the UV1164 triazine additive. However, the equivalent N-H polymeric HALS interacted in a complex manner with UV1164, giving synergism and antagonism, depending on HALS/UV1164 ratio. Strong synergism was evident with the monomeric HALS when the total stabilizer level was 0.2% w/w. Reduction in the overall stabilizer level to 0.05% w/w eliminated the synergism. The UV1164 alone led to rapid and intense yellowing; however, the rate and intensity of yellowing reduced dramatically upon combination with HALS, particularly when the UV1164 level was above 0.1% w/w. When the formulation was under UV attack, the molar mass and the type of N-substitution had no influence on stabilization performance because of the relatively low temperature of testing (leading to reduced volatilization), and the similarly effective UV-stabilization routes for N-methyl HALS and N-H HALS. Under UV attack, yellowing reached a maximum and then decreased to approximately the initial level, while HALS/UV1164 combinations generally showed weak antagonism.en
dc.language.isoenen
dc.publisherJohn Wiley & Sonsen
dc.relation.urlhttp://doi.wiley.com/10.1002/vnl.20011en
dc.subjectPhoto-stabilizationen
dc.subjectSynergismen
dc.titleEffect of hindered piperidine light stabilizer molecular structure and UV-absorber addition on the oxidation of HDPE. Part 1: Long-term thermal and photo-oxidation studiesen
dc.typeArticleen
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