Grafting of polyethylene onto graphite oxide sheets: a comparison of two routes

Abstract

International audiencePolyethylenes and azide-terminated polyethylenes can be converted to macroradicals and nitrenes, respectively followed by addition reactions onto the unsaturated system of graphite oxide sheets. For the first time, the addition of these macroradicals to graphite oxide sheets was compared by performing grafting reactions at 190 degrees C in 1,2,4-trichlorobenzene as a solvent and at 100 degrees C followed by a solvothermal reduction at 150 degrees C in a solvent mixture of 1,4-dioxane and 1,2-dichlorobenzene. Dispersion of PE coated graphite oxide in a DMF-heptane mixture was utilised to follow the introduction of polyethylene onto the GO sheet surface while the thermogravimetric analysis indicated the extent of this grafting. The grafting ratio was found to be in the 1.5 wt% range and despite this low grafting content, the amount of grafted PE was high enough to dramatically improve the affinity of GO with the heptane phase in the DMF-heptane (50/50 v/v) mixture. Polyethylene functionalised GO was imaged by scanning electron microscopy showing a significant difference in morphology between the two grafting paths. It was found that a higher level of grafting was obtained using a radical grafting reaction in the presence of benzoyl peroxide rather than the thermal cleavage of PE-N-3 onto GO while a similar grafting content was obtained with the thermal cleavage of PE-N-3 onto GO grafted trimethoxy(7-octen-1-yl)silane

Effect of polymer modifier chain length on thermal conductive property of polyamide 6/graphene nanocomposites

“…This result indicates that d spacing is increased. In addition, the peak at 11.3° became gradually sharp, representing a better regularity and crystallinity, which may explain the formation of crystals [31].…”

Functionalization of graphene using deep eutectic solvents

“…This agreed with the findings of a previous study that used the same type of graphene [ 63 ]. After mild oxidation with KMnO 4 , a prominent diffraction peak appeared at 2θ = 11.16°, reflecting the interlayer spacing of 0.79 nm (according to Bragg’s law [ 64 , 65 ]). The small peak at 2θ = ~26° suggests the existence of unoxidized graphene [ 66 ].…”

Sulfonated graphene oxide–silica for highly selective Nafion-based proton exchange membranes

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