Graphene-Rubber Nanocomposites Offers Similar Characteristics like Carbon Nanotube Composites but Are Much Cheaper to Make
The Trustees of Princeton University (Princeton, NJ) received U.S. Patent 7,745,528 for functional graphene-rubber nanocomposites. The graphene can be produced at a much lower cost than carbon nanotubes but offers similar characteristics to carbon nanotube composites. The functional graphene-polymer nanocomposite is made by either solution or melt processing of polymer matrix and functionalized graphene sheets (FGS).
Princeton Professor of Chemical and Biological Engineering, Director, Program in Engineering Biology Robert Prud'Homme with Bulent Ozbas, Ilhan Aksay, Richard Register and Douglas Adamson invented a polymer composition, containing a polymer matrix which contains an elastomer; and a functional graphene which displays no signature of graphite and/or graphite oxide, as determined by X-ray diffraction. The graphene-rubber nanocomposite exhibits excellent strength, toughness, modulus, thermal stability and electrical conductivity.
The inventors of the graphene nanocomposites investigated the mechanical, thermal, electrical, and gas barrier properties of graphene filled polymer nanocomposites. Single graphene sheets with high surface area (>600 m2/g) are obtained from oxidation process that is followed by rapid exfoliation of graphite.
As a result of this process the graphene sheets are decorated mainly with epoxide, carboxylic acid and hydroxyl groups and, thus, unlike carbon nanotubes no surface functionalization is necessary to improve the dispersion of graphene fillers in the polymer matrix. In addition to vulcanized natural (NR) and styrene-butadiene (SBR) rubbers, polystyrene-polyisoprene-polystyrene (PS-PI-PS) and PDMS have been used as a matrix to study the dispersion of functional graphene (FG) and the resultant physical properties.
Exfoliated graphite offers the mechanical performance of CNTs at the price of clay fillers. Exfoliated graphite has the potential to generate a new class of affordable, high-performance nanocomposites.
The functional graphene-polymer nanocomposite can be employed in all the areas where polymers (plastics, rubber, elastomers, etc.) are used for gas barrier applications including tires and packaging. The functional graphene-polymer nanocomposite can be used in many areas where both traditional and nano-composites are used including tires, bladder, packaging material, and in other areas where good gas permeation, mechanical and electrical properties are required.
The material is relatively easy to manufacture compared to other nano-sized filler that are used in the composites. Unlike other available fillers in the industry (carbon nanotubes, clay, carbon black), properties such as electrical conductivity, low gas permeation, high strength and high modulus can be all accessed in the same material due to graphene's plate like structure.
Click on the Headlines for the full story