Adding graphene to thin rubber films can make them stronger and stretchier, an advance with numerous applications including the development of sturdier condoms.
This is the claim of Dr Aravind Vijayaraghavan and Dr Maria Iliut from Manchester University who’ve added very small amounts of graphene to rubber films to increase their strength and the elasticity by up to 50 per cent. Their work is described in Carbon.
In their experiments, the scientists added graphene of different kinds, amounts and size to natural rubber, comprised of polyisoprene, and man-made polyurethane.
In most cases, they observed that the resulting composite material could be stretched to a greater degree and with greater force before it broke. Adding one tenth of one per cent of graphene is said to have made the rubber 50 per cent stronger.
Dr Iliut said: “We use a form of graphene called graphene oxide, which unlike graphene is stable as a dispersion in water. The rubber materials are also in a form that is stable in water, allowing us to combine them before forming thin films with a process called dip moulding.”
“The important thing here is that because these films are so thin, we need a strengthening filler which is also very thin. Fortunately, graphene is both the thinnest and strongest material we know of.”
The project emerged from a call by the Bill & Melinda Gates Foundation to develop a more desirable condom. According to Dr Vijayaraghavan, this composite material has tnumerous implications in daily life.
He said: “Our thinking was that if we could make the rubber used in condoms stronger and stretchier, then you could use that to make even thinner condoms which would feel better without breaking.
“Similar arguments can be made for using this material to make better gloves, sportswear, medical devices and so on. We are seeing considerable industrial interest in this area and we hope more companies will want to get involved in the commercial opportunities this research could create.”