Covalent polymer functionalization of graphene for improved dielectric properties and thermal stability of epoxy composites

Yanjun Jean Wan, Wen Hu Yang, Shu Hui Yu, Rong Sun, Ching Ping Wong, Wei Hsin Liao

Research output: Contribution to journalArticle

92 Citations (Scopus)

Abstract

Incorporation of conductive fillers into polymeric matrix to fabricate the composites with light-weight and excellent dielectric performance has been considered as one of the most promising processes. However, the inevitable high dielectric loss of the composites is still an obstacle for their practical applications, which has become a challenge for a long time, and the solution for this issue is still an open question. In this study, diglycidyl ether of bisphenol-A (DGEBA) molecules were used and grafted onto reduced graphene oxide (RGO) to synthesize DGEBA functionalized RGO (DGEBA-RGO). Various characterizations including TEM, FTIR, UV-visual spectrum, TGA, Raman spectrum and XRD revealed that the DGEBA molecules were grafted onto RGO sheets successfully. The DGEBA-RGO sheets were found to significantly improve the dielectric properties and thermal stability of epoxy compared to the corresponding graphene oxide (GO) and untreated RGO sheets. For instance, at 1 kHz, epoxy composites filled with 1.00 wt% DGEBA-RGO sheets showed a dielectric constant of ~32 at room temperature, which is over 9 times higher than that of neat epoxy (~3.5); meanwhile, the dielectric loss of the composites was suppressed and only 0.08. The enhanced dielectric properties can be well interpreted by the duplex interfacial polarization and the micro-capacitor model. The above outstanding properties should be ascribed to the well dispersion of DGEBA-RGO and the strong interaction between the filler and polymer matrix, which are induced by effective package of grafted DGEBA molecules on the graphene surface.

Original languageEnglish (US)
Pages (from-to)27-35
Number of pages9
JournalComposites Science and Technology
Volume122
DOIs
StatePublished - Jan 18 2016

Fingerprint

Graphite
Dielectric properties
Graphene
Oxides
Polymers
Thermodynamic stability
Ethers
Composite materials
Dielectric losses
Molecules
Fillers
2,2-bis(4-glycidyloxyphenyl)propane
Polymer matrix
Raman scattering
Capacitors
Permittivity
Polarization
Transmission electron microscopy

Keywords

  • Dielectric properties
  • Polymer-matrix composites (PMCs)
  • Scanning electron microscopy
  • Thermal stability

ASJC Scopus subject areas

  • Ceramics and Composites
  • Engineering(all)

Cite this

Covalent polymer functionalization of graphene for improved dielectric properties and thermal stability of epoxy composites. / Wan, Yanjun Jean; Yang, Wen Hu; Yu, Shu Hui; Sun, Rong; Wong, Ching Ping; Liao, Wei Hsin.

In: Composites Science and Technology, Vol. 122, 18.01.2016, p. 27-35.

Research output: Contribution to journalArticle

Wan, Yanjun Jean ; Yang, Wen Hu ; Yu, Shu Hui ; Sun, Rong ; Wong, Ching Ping ; Liao, Wei Hsin. / Covalent polymer functionalization of graphene for improved dielectric properties and thermal stability of epoxy composites. In: Composites Science and Technology. 2016 ; Vol. 122. pp. 27-35.
@article{4679f5add5c54e67a144f1f988204d34,
title = "Covalent polymer functionalization of graphene for improved dielectric properties and thermal stability of epoxy composites",
abstract = "Incorporation of conductive fillers into polymeric matrix to fabricate the composites with light-weight and excellent dielectric performance has been considered as one of the most promising processes. However, the inevitable high dielectric loss of the composites is still an obstacle for their practical applications, which has become a challenge for a long time, and the solution for this issue is still an open question. In this study, diglycidyl ether of bisphenol-A (DGEBA) molecules were used and grafted onto reduced graphene oxide (RGO) to synthesize DGEBA functionalized RGO (DGEBA-RGO). Various characterizations including TEM, FTIR, UV-visual spectrum, TGA, Raman spectrum and XRD revealed that the DGEBA molecules were grafted onto RGO sheets successfully. The DGEBA-RGO sheets were found to significantly improve the dielectric properties and thermal stability of epoxy compared to the corresponding graphene oxide (GO) and untreated RGO sheets. For instance, at 1 kHz, epoxy composites filled with 1.00 wt{\%} DGEBA-RGO sheets showed a dielectric constant of ~32 at room temperature, which is over 9 times higher than that of neat epoxy (~3.5); meanwhile, the dielectric loss of the composites was suppressed and only 0.08. The enhanced dielectric properties can be well interpreted by the duplex interfacial polarization and the micro-capacitor model. The above outstanding properties should be ascribed to the well dispersion of DGEBA-RGO and the strong interaction between the filler and polymer matrix, which are induced by effective package of grafted DGEBA molecules on the graphene surface.",
keywords = "Dielectric properties, Polymer-matrix composites (PMCs), Scanning electron microscopy, Thermal stability",
author = "Wan, {Yanjun Jean} and Yang, {Wen Hu} and Yu, {Shu Hui} and Rong Sun and Wong, {Ching Ping} and Liao, {Wei Hsin}",
year = "2016",
month = "1",
day = "18",
doi = "10.1016/j.compscitech.2015.11.005",
language = "English (US)",
volume = "122",
pages = "27--35",
journal = "Composites Science and Technology",
issn = "0266-3538",
publisher = "Elsevier BV",

}

TY - JOUR

T1 - Covalent polymer functionalization of graphene for improved dielectric properties and thermal stability of epoxy composites

AU - Wan, Yanjun Jean

AU - Yang, Wen Hu

AU - Yu, Shu Hui

AU - Sun, Rong

AU - Wong, Ching Ping

AU - Liao, Wei Hsin

PY - 2016/1/18

Y1 - 2016/1/18

N2 - Incorporation of conductive fillers into polymeric matrix to fabricate the composites with light-weight and excellent dielectric performance has been considered as one of the most promising processes. However, the inevitable high dielectric loss of the composites is still an obstacle for their practical applications, which has become a challenge for a long time, and the solution for this issue is still an open question. In this study, diglycidyl ether of bisphenol-A (DGEBA) molecules were used and grafted onto reduced graphene oxide (RGO) to synthesize DGEBA functionalized RGO (DGEBA-RGO). Various characterizations including TEM, FTIR, UV-visual spectrum, TGA, Raman spectrum and XRD revealed that the DGEBA molecules were grafted onto RGO sheets successfully. The DGEBA-RGO sheets were found to significantly improve the dielectric properties and thermal stability of epoxy compared to the corresponding graphene oxide (GO) and untreated RGO sheets. For instance, at 1 kHz, epoxy composites filled with 1.00 wt% DGEBA-RGO sheets showed a dielectric constant of ~32 at room temperature, which is over 9 times higher than that of neat epoxy (~3.5); meanwhile, the dielectric loss of the composites was suppressed and only 0.08. The enhanced dielectric properties can be well interpreted by the duplex interfacial polarization and the micro-capacitor model. The above outstanding properties should be ascribed to the well dispersion of DGEBA-RGO and the strong interaction between the filler and polymer matrix, which are induced by effective package of grafted DGEBA molecules on the graphene surface.

AB - Incorporation of conductive fillers into polymeric matrix to fabricate the composites with light-weight and excellent dielectric performance has been considered as one of the most promising processes. However, the inevitable high dielectric loss of the composites is still an obstacle for their practical applications, which has become a challenge for a long time, and the solution for this issue is still an open question. In this study, diglycidyl ether of bisphenol-A (DGEBA) molecules were used and grafted onto reduced graphene oxide (RGO) to synthesize DGEBA functionalized RGO (DGEBA-RGO). Various characterizations including TEM, FTIR, UV-visual spectrum, TGA, Raman spectrum and XRD revealed that the DGEBA molecules were grafted onto RGO sheets successfully. The DGEBA-RGO sheets were found to significantly improve the dielectric properties and thermal stability of epoxy compared to the corresponding graphene oxide (GO) and untreated RGO sheets. For instance, at 1 kHz, epoxy composites filled with 1.00 wt% DGEBA-RGO sheets showed a dielectric constant of ~32 at room temperature, which is over 9 times higher than that of neat epoxy (~3.5); meanwhile, the dielectric loss of the composites was suppressed and only 0.08. The enhanced dielectric properties can be well interpreted by the duplex interfacial polarization and the micro-capacitor model. The above outstanding properties should be ascribed to the well dispersion of DGEBA-RGO and the strong interaction between the filler and polymer matrix, which are induced by effective package of grafted DGEBA molecules on the graphene surface.

KW - Dielectric properties

KW - Polymer-matrix composites (PMCs)

KW - Scanning electron microscopy

KW - Thermal stability

UR - http://www.scopus.com/inward/record.url?scp=84947793124&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84947793124&partnerID=8YFLogxK

U2 - 10.1016/j.compscitech.2015.11.005

DO - 10.1016/j.compscitech.2015.11.005

M3 - Article

VL - 122

SP - 27

EP - 35

JO - Composites Science and Technology

JF - Composites Science and Technology

SN - 0266-3538

ER -