S5.3

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S5.3
Thermoplastic Elastomeric Nanocomposites prepared via in situ
dynamic vulcanization and chain-exchange reactions
Chaoying Wan1, Wenjing Wu2, Yong Zhang2
International Institute for Nanocomposites Manufacturing, WMG, University of Warwick, CV4 7AL, UK
2
School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 200240, China
(chaoying.wan@warwick.ac.uk)
1
Abstract
Thermoplastic elastomers (TPEs) combining good mechanical properties, heat/oil
resistance and chemical stability of both thermoplastics and elastomers have found
wide applications in the fields of automobile, sports and electronic appliances. In this
study, polyamide/ethylene-vinyl acetate rubber (PA/EVM) based TPEs in the presence
of graphene oxide (GO) were prepared via dynamic vulcanization and chain-exchange
reactions. The reaction mechanisms of a sequential ring-opening ester-amide exchange
reaction between caprolactam (CL) monomer and acetate groups of EVM with and
without GO were proposed and investigated. Under the reaction conditions, the yield of
the copolymer out of the CL/EVM (60/40) mixture was 26.4 wt% at 15% of the conversion of
CL. The graft PA6 content was determined to be 4~6 wt%, and the grafting efficiency was
further enhanced up to 13.1 wt% with the incorporation of 0.7 wt% of GO. This suggested
that GO accelerated the polymerization reaction of CL, and also acted as a crosslinking
agent to bridge homopolymerised PA6 with EVM-g-PA6 copolymer. In addition, GO
was thermally reduced in situ during the reaction process, thus significantly enhanced
both the volume conductivity and permittivity of the copolymers. With the addition
of 2.3 wt% of GO, the stress at 100% extension of the copolymer was further enhanced
by 190%, and Young’s modulus was improved by 109%. The EVM-g-PA6 copolymer and
the GO reinforced copolymeric nanocomposites show a great potential as engineering
thermoplastic elastomers.
References
1) W Wu, C Wan, S Wang, Y Zhang. Physical properties and crystallization behavior of ethylene-vinyl acetate
rubber/polyamide/graphene oxide thermoplastic elastomer nanocomposites. RSC Adv, 2013, 3, 26166-26176
2) W Wu, C Wan, Y Zhang. EVM-g-PA6 thermoplastic elastomeric nanocomposites with graphene oxide as a
covalent-crosslink agent, submitted, Polymer, 2014.
Short Biography
Dr Chaoying Wan is Assistant Professor in Nanocomposites in WMG since 2012. She
gained a PhD degree in Materials Science in 2004, and conducted postdoctoral research
at Loughborough University UK from 2006 to 2008. She was a Marie Curie Fellow at
Trinity College Dublin during 2009 and 2011. Her research interest is in the chemistry and
physics of nanomaterials, manufacturing functional polymer nanocomposites for energy
storage.
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