Dr.AravindVijayaraghavan and Dr. Maria Iliut from the University ofManchester, UK have shown in an article they published that adding a very small amount of graphene, the world’s thinnest and strongest material, to rubber films can increase both their strength and the elasticity by up to 50%. Thin rubber films are ubiquitous in daily life, used in everything from gloves to condoms.
In their experiments, the scientists tested two kinds of rubbery materials – natural rubber, comprised of a material called polyisoprene, and a man-made rubber called polyurethane. To these, they added graphene of different kinds, amounts and size.
In most cases, they observed that the resulting composite material could be stretched to a greater degree and with greater force before it broke. Indeed, adding just one tenth of 1% of graphene was all it took to make the rubber 50% stronger.
“A composite is a material which contains two parts, a matrix which is soft and light and a filler which is strong. Taken together, you get something which is both light and strong. This is the principle behind carbon fibre composites used in sports cars, or Kevlar composites used in body armour,” Vijayaraghavan explains.
In this case, they created a composite of soft, stretchy and fragile rubber with graphene that resulted in a stronger and stretchier material.
Iliut describes how the material is produced: “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 Vijayaraghavan, this composite material has tremendous implications in daily life.
He says if they could make rubber materials that are stronger and stretchier, they could use that to make thinner condoms as well as better gloves, sportswear, medical devices and many other products.
Source: Manchester