E. Beyou, A. Guimont, P. Cassagnau, G. Martin, P. Sonntag
Lyon1 University, France
pp. 165 - 168
Keywords: composites, graphene oxide sheets, functionalization, polyethylene, polydimethylsiloxane, electrical percolation thresholds, rheological percolation thresholds
The preparation of polyethylene/graphite oxide composites exhibiting rheological and electrical percolation thresholds was accomplished by radical addition reactions onto the unsaturated system of graphite oxide sheets through the use of pentadecane and polyethylene in presence of peroxides as well as azide-terminated polyethylenes. It was found that a higher level of grafting was obtained using a radical grafting reaction in presence of benzoyl peroxide rather than the thermal cleavage of PE-N3 onto GO while a similar grafting content was obtained with the thermal cleavage of PE-N3 onto GO grafted trimethoxy(7-octen-1-yl)silane. This chemical functionalization influences solubility behaviour of the formed pentadecane and polyethylene grafted GO sheets in various solvents. Moreover, the compounding of the composites pentadecane grafted GO/PE was performed at a processing temperature of 140°C with 25, 20, 15, 10, 8 and 5 wt% loadings. Rheological and electrical percolation thresholds were found between 10 and 15 wt% for polyethylene / pentadecane functionalized graphene oxide composites while the composite graphite/PE at the same loading percentage did not reach any percolation threshold.