Application of bio-resin in road materials: Rheological and chemical properties of asphalt binder modified by lignin-phenolic resin

Abstract

The development of new sustainable green road materials with bio-resin is a hot topic in pavement engineering. To improve the efficiency of lignin as a sustainable pavement material, an asphalt binder modified by lignin-based resin was prepared, and its properties were evaluated. Firstly, lignin was extracted from biomass (corn straw) by thermochemical method to prepare lignin-based phenol formaldehyde (LPF) resin. After that, LPF resin-modified asphalt and phenol formaldehyde (PF) resin-modified asphalt were prepared. Then the effects of LPF resin and PF resin on asphalt properties were evaluated by chemical analysis and rheological performance tests. The results showed that lignin was involved in resin synthesis, LPF resin with PF resin had similar thermogravimetric curves, and the thermal stability of LPF resin was slightly lower than PF resin. Both LPF resin and PF resin can increase the proportion of large-size molecules and elastic components of asphalt binder and enhance its high-temperature deformation recovery ability. Moreover, the fatigue performance and aging resistance of the binder were also enhanced by the addition of LPF resin and PF resin. Although the addition of LPF resin and PF resin will increase the G-R parameters of virgin asphalt binder, it can reduce the effect of aging on the G-R parameters of asphalt binder. It seems that LPF resin and PF resin can improve the cracking resistance of asphalt binders.