Properties of paving epoxy asphalt with epoxy-terminated hyperbranched polyester

Epoxy asphalt is a high performance pavement material, but the poor toughness of epoxy asphalt at low temperature has limited its utilisation. Hyperbranched polyester (HBP) is a spherical polymer with highly branched structures, which can effectively improve the toughness of epoxy asphalt. However, hydroxyl-terminated HBP would accelerate the reaction rate of epoxy asphalt because of the rapid reaction between hydroxyl groups of HBP and epoxy groups of resin. We modified the hydroxyl end groups of HBP as epoxy end groups to avoid its curing reaction with epoxy resin and further reduce the viscosity of epoxy asphalt. Epoxy-terminated HBP also has good compatibility with epoxy resin to improve phase structure uniformity of epoxy asphalt. Moreover, with the help of hyperbranched structure, epoxy-terminated HBP still can improve the toughness of epoxy asphalt, which can be proved by the fracture surface morphology, mechanical properties, and dynamic thermomechanical properties.

Automated summary

In this study, the modification of hydroxyl-terminated hyperbranched polyester (HBP) to epoxy-terminated HBP successfully improved the toughness of epoxy asphalt at low temperature. Epoxy-terminated HBP exhibited good compatibility with epoxy resin and could still enhance the toughness of epoxy asphalt through its hyperbranched structure.