Enhanced strength and toughness of polyurethane rubber by introducing hydrogen bond sacrificial units at rubber‐graphene interfaces

It is still a huge challenge to add a kind of filler into rubber toward strong yet tough elastomer. In this work, a biomimetic design for polyurethane rubber (PUR) by introducing hydrogen bond sacrificial units at the rubber‐graphene oxide interfaces was described. Poly(vinyl alcohol)‐g‐graphene oxide (PGO) reinforced PUR composites were prepared by mechanical blending. The grafting rate of poly(vinyl alcohol) (PVA) on graphene oxide (GO) surface was 23.5%. The improved properties, including the tensile strength, elongation at break and thermal stability of the PUR/PGO composites compared to the virgin PUR vulcanizate were attributed to the hydrogen bonds between PUR and PGO. An 131.2% increase in the tensile strength, a 60.2% increase in the elongation at break and a 23.5°C increase in the maximum decomposition temperature were obtained by adding 1 phr PGO. In addition, the low temperature resistance of the PUR vulcanizate was improved with the addition of PGO. The mechanism of improved properties was attributed to the destruction and reconstitution of hydrogen bond sacrificial units in the PUR/PGO system.