Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Analytical strategies for the quality assessment of recycled high-impact polystyrene: A combination of thermal analysis, vibrational spectroscopy, and chromatography
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.ORCID iD: 0000-0003-3572-7798
Instituto de Tecnología de Materiales (ITM), Universidad Politécnica de Valencia.
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.ORCID iD: 0000-0002-5394-7850
2007 (English)In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 604, no 1, 18-28 p.Article in journal (Refereed) Published
Abstract [en]

Various analytical techniques (thermal analysis, vibrational spectroscopy, and chromatographic analysis) were used in order to monitor the changes in polymeric properties of recycled high-impact polystyrene (HIPS) throughout mechanical recycling processes. Three key quality properties were defined and analysed; these were the degree of mixing (composition), the degree of degradation, and the presence of low molecular weight compounds. Polymeric contaminations of polyethylene (PE) and polypropylene (PP) were detected in some samples using differential scanning calorimetry (DSC). Vibrational spectroscopy showed the presence of oxidised parts of the polymeric chain and gave also an assessment of the microstructure of the polybutadiene phase in HIPS. The presence of low molecular weight compounds in the HIPS samples was demonstrated using microwave assisted extraction followed by gas chromatography mass spectrometry (GC-MS). Several volatile organic compounds (VOCs), residues from the polymerisation, additives, and contaminations were detected in the polymeric materials. Styrene was identified already in virgin HIPS; in addition, benzaldehyde, alpha-methylbenzenaldehyde, and acetophenone were detected in recycled HIPS. The presence of oxygenated derivates of styrene may be attributed to the oxidation of polystyrene (PS). Several styrene dimers were found in virgin and recycled HIPS; these are produced during polymerisation of styrene and retained in the polymeric matrix as polymerisation residues. The amount of these dimers was highest in virgin HIPS, which indicated that emission of these compounds may have occurred during the first lifetime of the products. This paper demonstrates that a combination of different analytical strategies is necessary to obtain a detailed understanding of the quality of recycled HIPS.

Place, publisher, year, edition, pages
2007. Vol. 604, no 1, 18-28 p.
Keyword [en]
recycling, quality analysis, high-impact polystyrene, degradation, thermal analysis, vibrational spectroscopy, chromatographic techniques
National Category
Polymer Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-4892DOI: 10.1016/j.aca.2007.04.046ISI: 000251293700004Scopus ID: 2-s2.0-35648936956OAI: oai:DiVA.org:kth-4892DiVA: diva2:1796
Note
QC 20100920Available from: 2008-09-17 Created: 2008-09-17 Last updated: 2010-09-20Bibliographically approved
In thesis
1. Quality Assessment for the Improved Use of Recycled Styrenic Polymers: Application to packaging and electronic waste
Open this publication in new window or tab >>Quality Assessment for the Improved Use of Recycled Styrenic Polymers: Application to packaging and electronic waste
2008 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

 Polymeric waste materials should be considered resources for the manufacture of new products through recycling processes, with a similar status as virgin fossil-based plastics and biopolymers from renewable resources. Several efforts can be done to achieve this qualitative quantum leap and introduce recycled products in the market with competitive performance. Detailed scientific knowledge about the degradation processes to which polymeric materials are subjected under their life cycle is important when discussing their further waste recovery possibilities and the performance of recycled plastic. The development of fast and reliable analytical methods for the quality assessment of recycled plastics is fundamental to guarantee their performance in new applications. Three key quality properties have been previously defined for this quality analysis: degree of mixing (composition), degree of degradation, and presence of low molecular weight compounds (degradation products, contaminants, additives).A dual experimental approach employing multiple processing and thermooxidation is proposed to model the life cycle of recycled high-impact polystyrene (HIPS) used in packaging applications, and in electrical and electronic equipment (E&E). Both reprocessing and thermo-oxidative degradation are responsible for coexistent physical and chemical effects (chain scission, crosslinking, apparition of oxidative moieties, polymeric chain rearrangements, and probably physical ageing) on the microstructure and morphology of polybutadiene (PB) and polystyrene (PS) phases; these effects ultimately influence the long-term stability, and the rheological and mechanical behaviour of HIPS. The PB phase has proved to be the initiation point of HIPS degradation throughout the life cycle. Thermo-oxidation seems to have more severe effects on HIPS properties; therefore, it can be concluded that previous service life may be the part of the life cycle with the greatest influence on the recycling possibilities and performance of HIPS recyclates in second-market applications.Different strategies are presented for the quality analysis of recycled styrenic polymers from packaging waste and electrical and electronic equipment. The results from the life cycle degradation simulation were compared with those obtained from real samples from a large-scale mechanical recycling plant. The presence and emission of low molecular weight compounds from recycled HIPS from packaging waste has been critically discussed using solvent and headspace extraction procedures. Special attention has been devoted to the determination of brominated flame retardants in recycled HIPS from electrical and electronic equipment using advanced extraction and chromatographic techniques, due to the legislative and environmental implications of these additives.

Place, publisher, year, edition, pages
Stockholm: KTH, 2008. 57 p.
Series
Trita-CHE-Report, ISSN 1654-1081 ; 2008:63
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-4895 (URN)978-91-7415-112-1 (ISBN)
Public defence
2008-10-09, F3, Lindstedtsvägen 26, Stockholm, 10:00 (English)
Opponent
Supervisors
Note
QC 20100920Available from: 2008-09-25 Created: 2008-09-17 Last updated: 2010-09-20Bibliographically approved
2. Modelling the degradation processes in high-impact polystyrene during the first use and subsequent recycling
Open this publication in new window or tab >>Modelling the degradation processes in high-impact polystyrene during the first use and subsequent recycling
2007 (English)Licentiate thesis, comprehensive summary (Other scientific)
Abstract [en]

Polymers are subjected to physical and chemical changes during their processing, service life, and further recovery, and they may also interact with impurities that can alter their composition. These changes substantially modify the stabilisation mechanisms and mechanical properties of recycled polymers. Detailed knowledge about how the different stages of their life cycle affect the degree of degradation of polymeric materials is important when discussing their further waste recovery possibilities and the performance of recycled plastics. A dual-pronged experimental approach employing multiple processing and thermo-oxidation has been proposed to model the life cycle of recycled high-impact polystyrene (HIPS). Both reprocessing and thermo-oxidative degradation are responsible for coexistent physical and chemical effects (chain scission, crosslinking, apparition of oxidative moieties, polymeric chain rearrangements, and physical ageing) on the microstructure and morphology of polybutadiene (PB) and polystyrene (PS) phases; these effects ultimately influence the long-term stability, and the rheological and mechanical behaviour of HIPS. The PB phase has proved to be the initiation point of HIPS degradation throughout the life cycle. Thermo-oxidation seems to have more severe effects on HIPS properties; therefore, it can be concluded that previous service life may be the part of the life cycle with the greatest influence on the recycling possibilities and performance of HIPS recyclates in second-market applications. The results from the life cycle degradation simulation were compared with those obtained from real samples from a large-scale mechanical recycling plant. A combination of different analytical strategies (thermal analysis, vibrational spectroscopy, and chromatographic analysis) is necessary to obtain a detailed understanding of the quality of recycled HIPS as defined by three key properties: degree of mixing, degree of degradation, and presence of low molecular weight compounds.

Place, publisher, year, edition, pages
Stockholm: KTH, 2007. 39 p.
Series
Trita-CHE-Report, ISSN 1654-1081 ; 2007:30
Keyword
Recycling; high-impact polystyrene; degradation; quality analysis; thermal analysis; vibrational spectroscopy; chromatography techniques; thermo-oxidation; reprocessing; dynamic mechanical properties; polybutadiene microstructure.
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-4407 (URN)978-91-7178-678-4 (ISBN)
Presentation
2007-06-07, E2, Osquars backe 14, Stokcholm, 10:00
Opponent
Supervisors
Note
QC 20101119Available from: 2007-05-30 Created: 2007-05-30 Last updated: 2010-11-19Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Authority records BETA

Vilaplana, FranciscoKarlsson, Sigbritt

Search in DiVA

By author/editor
Vilaplana, FranciscoKarlsson, Sigbritt
By organisation
Fibre and Polymer Technology
In the same journal
Analytica Chimica Acta
Polymer Chemistry

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 126 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf