Bonding nanoparticles to rubber increases material’s fatigue resistance sixfold

Strategically embedding rigid particles around long polymer chains can dissipate stress in rubber and increase the fatigue threshold sixfold, researchers in the US have shown. This potentially opens a ‘new paradigm’ for the design of stiff, fatigue-resistant rubbers in applications such as textured belts, tyre treads and soft robotics.

A filled rubber is a composite material held together by a matrix of elastic polymer chains and stiffened by rigid particles such as carbon black or silica. The filler material can increase the elastic modulus of the rubber by two orders of magnitude, making composite materials extremely useful for applications like tyres. It does not, however, significantly increase the fatigue threshold (the cumulative amount of energy the material can absorb over repeated deformation cycles before failing).