Polyethylene/reduced graphite oxide nanocomposites with improved morphology and conductivity

POLYMER

卷:81

Article

Pavoski, Giovani¹  Maraschin, Thuany²  Milani, Marceo A.¹  Azambuja, Denise S.¹  Quijada, Raul³  Moura, Cassio Stein⁴  Basso, Nara de Sousa²  Galland, Griselda Barrera¹ 

[1] Univ Fed Rio Grande do Sul, Inst Quim, Ave Bento Goncalves 9500, BR-91501970 Porto Alegre, RS, Brazil

[2] Pontificia Univ Catolica Rio Grande do Sul, Fac Quim, BR-90619900 Porto Alegre, RS, Brazil

[3] Univ Chile, Fac Ciencias Fis & Matemat, Dept Ingn Quim & Biotecnol, Santiago, Chile

[4] Pontificia Univ Catolica Rio Grande do Sul, Fac Fis, Porto Alegre, RS, Brazil

关键词: Polyethylene;    Nanocomposites;    Graphene;    Morphology;    Conductivity;    Reduced graphite oxide;   

DOI  :  10.1016/j.polymer.2015.11.019

来源: Elsevier

【 摘 要 】

The use of graphite and polyolefins as starting materials to prepare nanocomposites is convenient because both are inexpensive and have very different properties, one is conductive and the other is insulating. The formation of nanocomposites can extend the applicability of both commodities. In this work we synthesized nanocomposites of polyethylene (PE) with two types of graphites, graphite oxide (GO) and reduced graphite oxide (RGO), by in situ polymerization using a supported metallocene catalyst. The functional groups on the graphites were used to support the metallocene catalyst by a previous treatment with methylaluminoxane. The nanocomposites were obtained with good catalytic activities and presented excellent morphology and dispersion; their elastic modulus and crystallization temperatures were higher than those of neat PE. However, the nanocomposites PEGO were insulant, whereas PERGO had a conductivity of 1.1 x 10(-5) S cm(-1) with 3.1 wt% filler. This is a significant result compared to the conductivity obtained using non-supported graphite nanosheets where more than 15 wt% of graphite nanosheets are needed to obtain conductivities higher than 10(-7) S cm(-1). This improvement in the percolation threshold was attributed to the good morphology of the PERGO nanocomposites obtained due to the control of the graphitic sheets and the support methodology. (C) 2015 Elsevier Ltd. All rights reserved.

【 授权许可】

Free