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Degradation and Stabilization of Polyurethane Elastomers

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Degradation and Stabilization of Polyurethane Elastomers Manuscript version: Author’s Accepted Manuscript The version presented in WRAP is the author’s accepted manuscript and may differ from the published version or Version of Record. Persistent WRAP URL: http://wrap.warwick.ac.uk/112512 How to cite: Please refer to published version for the most recent bibliographic citation information. If a published version is known of, the repository item page linked to above, will contain details on accessing it. Copyright and reuse: The Warwick Research Archive Portal (WRAP) makes this work by researchers of the University of Warwick available open access under the following conditions. © 2018 Elsevier. Licensed under the Creative Commons Attribution-NonCommercial- NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/. Publisher’s statement: Please refer to the repository item page, publisher’s statement section, for further information. For more information, please contact the WRAP Team at: [email protected]. warwick.ac.uk/lib-publications Accepted Manuscript Title: Degradation and stabilization of polyurethane elastomers Authors: Fengwei Xie, Tianlong Zhang, Peter Bryant, Valsala Kurusingal, John M. Colwell, Bronwyn Laycock PII: S0079-6700(18)30299-5 DOI: https://doi.org/10.1016/j.progpolymsci.2018.12.003 Reference: JPPS 1117 To appear in: Progress in Polymer Science Received date: 27 August 2018 Revised date: 22 December 2018 Accepted date: 27 December 2018 Please cite this article as: Xie F, Zhang T, Bryant P, Kurusingal V, Colwell JM, Laycock B, Degradation and stabilization of polyurethane elastomers, Progress in Polymer Science (2018), https://doi.org/10.1016/j.progpolymsci.2018.12.003 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Degradation and stabilization of polyurethane elastomers Fengwei Xie a,b,c,d,1 , Tianlong Zhang a,b, Peter Bryant e, Valsala Kurusingal e, John M. Colwell b,f, Bronwyn Laycock a,b,1 aSchool of Chemical Engineering, The University of Queensland, Brisbane, Qld 4072, Australia bDefence Materials Technology Centre (DMTC), Level 2, 24 Wakefield St., Hawthorn, Vic 3122, Australia cInstitute of Advanced Study, University of Warwick, Coventry CV4 7HS, United Kingdom dInternational Institute for Nanocomposites Manufacturing (IINM), WMG, University of Warwick, Coventry CV4 7AL, United Kingdom eThales Australia, Rydalmere, NSW 2116, Australia fSchool of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), GPO Box 2434, Brisbane, QLD, Australia 1 Corresponding author: [email protected]; [email protected] 1 Co-corresponding author: [email protected] ‘ Graphical abstract Abstract: Polyurethane elastomers have a combination of excellent mechanical, physical and chemical properties along with exceptional biocompatibility. Therefore, these elastomeric systems are used in a diverse range of indoor, outdoor, underwater and biomedical applications. However, under certain conditions polyurethane elastomers undergo degradation, resulting in modified properties during usageACCEPTED or even complete failure. The degradation MANUSCRIPT will not only severely affect the quality of the associated items, devices, or instruments, but may also cause catastrophic outcomes risking people’s safety and health. This review presents a comprehensive survey of the literature regarding various types of degradation of polyurethane elastomers, including photo-, thermal, ozonolytic, hydrolytic, chemical, enzymatic, in-vivo/in-vitro oxidative, biological, and mechanical degradation. The stability of polyurethane elastomers based on different building blocks of macrodiols (polyester, polyether, 1 polycarbonate, polybutadiene, and polyisobutylene), isocyanates (aromatic and aliphatic), and chain extenders (diols, triols, and diamines) are summarised, and the mechanisms of different types of degradation are presented. The chemical components significantly influence not only the material structure and properties but also the degradative stability. Focussing on the components, we explore strategies for the enhancement of polyurethane stability through chemistry and engineering. A range of stabilizers, including both organic and inorganic additives for better stability against different types of degradation, are discussed, with a focus on their efficacy and mechanisms of action. A perspective on novel polyurethane materials with desired structures and properties combined with exceptional stability is also provided. Keywords: Polyurethane elastomers; photodegradation; thermal degradation; oxidation; ozone; hydrolysis; stabilization Contents 1. Introduction ............................................................................................................................................. 2. Polyurethane chemistry .......................................................................................................................... 2.1. General ........................................................................................................................................... 2.2. Macrodiols ....................................................................................................................................... 2.3. Isocyanates ..................................................................................................................................... 2.4. Chain extenders .............................................................................................................................. 2.5. Non-isocyanate polyurethanes ....................................................................................................... 3. Photodegradation and stabilization of polyurethane elastomers ........................................................... 3.1. Photodegradation of polymers ........................................................................................................ 3.2. Photodegradation of polyurethane elastomers ............................................................................... 3.3. Stabilization of polyurethane elastomers against photodegradation by polymer modification ...... 3.4. ACCEPTEDStabilization of polyurethane elastomers MANUSCRIPTagainst photodegradation using stabilizers ................... 4. Thermal degradation and stabilization of polyurethane elastomers ...................................................... 4.1. Thermal degradation of polymers ................................................................................................... 4.2. Thermal degradation of polyurethane elastomers .......................................................................... 4.3. Stabilization of polyurethane elastomers against thermal degradation by polymer modification .. 2 4.4. Stabilization of polyurethane elastomers against thermal degradation using stabilizers............... 5. Ozonolytic degradation and stabilization of polyurethane elastomers ................................................... 5.1. General ozonolytic degradation of polymers .................................................................................. 5.2. Ozonolytic degradation of polyurethane elastomers ...................................................................... 5.3. Stabilization of polyurethane elastomers against ozonolytic degradation by polymer modification 5.4. Stabilization of polyurethane elastomers against ozonolytic degradation using stabilizers........... 6. Hydrolytic degradation and stabilization of polyurethane elastomers .................................................... 6.1. Hydrolytic degradation of polyurethane elastomers ....................................................................... 6.2. Stabilization of polyurethane elastomers against hydrolytic degradation by polymer modification 6.3. Stabilization of polyurethane elastomers against hydrolytic degradation using stabilizers ........... 7. Chemical degradation of polyurethane elastomers................................................................................ 7.1. Chemical degradation by inorganic compounds ............................................................................ 7.2. Chemical degradation by organic compounds ............................................................................... 7.3. Calcification ..................................................................................................................................... 8. Enzymatic degradation and stabilization of polyurethane elastomers ................................................... 8.1. General discussion on enzymatic degradation of polyurethane elastomers .................................. 8.2. Enzymatic degradation of poly(ester-urethane) elastomers........................................................... 8.3. Enzymatic degradation of poly(ether-urethane) and poly(carbonate-urethane) elastomers ......... 9. In-vivo/in-vitro oxidative degradation and stabilization of polyurethane elastomers ............................. 9.1. In-vivo/in-vitro oxidative degradation of polyurethane elastomers ................................................
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