Hummers method of oxidation of graphite give graphene which is multilayered, hence referred as multilayered graphene in the literature. We have been dispersing graphene in polymer matrices as nanofillers to improve the mechanical properties of nano composites. We mix graphene at desired concentrations with the monomers, subject the mixture to sonication, and then crosslink the monomers to form polymeric nanocomposites. This method has been followed by Sitharaman and Mikos for fabrication of PPF nanocomposites using CNTs and fullerenes.

As far as epoxy and other resins are concerned, Tour et al have dispersed graphene nanoribbons in epoxy and performed the mechanical characterization of thermally crosslinked epoxy-graphene nanocomposites. Look at "graphene nanoribbon composites", ACS Nano, 2010, 4 (12), pp 7415–7420. I think if you want to functionalize graphene before its addition to the polymer matrix, you might want to try that out depending upon the possibilities of formation of crosslinks between the nanomaterials and your polymer (if the polymer is unsaturated). We, however, use grapheme oxide without any covalent functionalization. If you are going for non-covalent functionalization using DSPE-PEG or Pluronic, you will have to take into consideration the chances of phase separation.

Best of luck !

"multilayer graphene???"

Graphene define, is a single sheet..

any ways!!

Insted of chemical functionalization try the following things if possible,

- Physical grafting with polymeric material

- increase the ultrasound power & time, to confirm intercalation & exfoliation

- determine the percolation threshold for your process, to improve conductive property of your composite

Regards..

Thank you for the answer. "Multilayer graphene’’ I mean it was chemically derived graphene so that it’s not a single layer graphene! Am I right?

I have another question: do you think the hummer’s method is a good way for the first step to oxidized GNP and after that grafting the other functional groups like silane.

depends on which type of silane you want to graft... if its aminosilane or simple ones like GTPMS or IPTES, then GO by hummers method is a good start.

Hummers method of oxidation of graphite give graphene which is multilayered, hence referred as multilayered graphene in the literature. We have been dispersing graphene in polymer matrices as nanofillers to improve the mechanical properties of nano composites. We mix graphene at desired concentrations with the monomers, subject the mixture to sonication, and then crosslink the monomers to form polymeric nanocomposites. This method has been followed by Sitharaman and Mikos for fabrication of PPF nanocomposites using CNTs and fullerenes.

As far as epoxy and other resins are concerned, Tour et al have dispersed graphene nanoribbons in epoxy and performed the mechanical characterization of thermally crosslinked epoxy-graphene nanocomposites. Look at "graphene nanoribbon composites", ACS Nano, 2010, 4 (12), pp 7415–7420. I think if you want to functionalize graphene before its addition to the polymer matrix, you might want to try that out depending upon the possibilities of formation of crosslinks between the nanomaterials and your polymer (if the polymer is unsaturated). We, however, use grapheme oxide without any covalent functionalization. If you are going for non-covalent functionalization using DSPE-PEG or Pluronic, you will have to take into consideration the chances of phase separation.

Best of luck !

First I assume you mean mix graphene nanoplates with epoxy or PU monomers then curing them.

For graphene without any function groups, so far it is still hard to disperse them well in polymer, if you don't add any compatibilizer. Personally I don't think ultrasonications is useful for it.

For graphene oxide or graphene with polar groups like COOH, amine, it is much easier to disperse them in polar polymer like PMMA, PLA. I think this strategy still works for epoxy, although may not be excellent.

For your case, if you concern about electrical conductivity, you can first mix graphene oxide with epoxy, then reduce the graphene oxide in polymer back to graphene. That is an effective way reported by R. Rudoff in UT Austin.

Check this out: http://www.ncbi.nlm.nih.gov/pubmed/23405887

Thank you for your answers.

dear Mr. Lalwani thank you so much for your consideration, unfortunately i couldn't get this article ( http://www.ncbi.nlm.nih.gov/pubmed/23405887 ), if there is posibility please send it to me ([email protected]

Hello Masoome,

You can go to my profile and download the full text. This paper talks about preparation of polymeric nanocomposites using graphene oxide as reinforcing agents. We have used sonication to disperse graphene oxide nanoplatelets in the polymer matrix and TEM analysis suggests good dispersion of the nanoparticles in the matrix.

Dear Mr.Gaurav

thank you so much for your kindly regard

i'm so surprised by your papers

Surprised ?