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Sasobit has been widely applied as warm-mix asphalt (WMA) additive in an environment friendly and energy saving pavement construction. Epoxy asphalt (EA) has been extensively used on the pavement of steel bridge decks. In the present paper, Sasobit was introduced into warm-mix epoxy asphalt binder (WEAB) to prepare Sasobit modified WEAB. The effect of Sasobit on the viscosity, thermal, damping and mechanical properties and morphology of the neat WEAB were investigated using various characterisation techniques. Sasobit significantly lowered the viscosity of the neat WEAB and prolonged the operational lifetime for mixture pavement. Sasobit lowered the glass transition temperature of the neat WEAB. Sasobit slightly decreases the damping properties and thermal stability of the neat WEAB. However, Sasobit increased the tensile strength of the neat WEAB. The crystalline network structures of Sasobit formed in asphalts were clearly observed. The lamellar crystalline structure of Sasobit turned to gel-like structure in curly ribbon shape with an increase of the WMA additive contents. Reaction-induced phase separation occurred in the neat WEAB and Sasobit modified WEABs. No crystalline network structures of Sasobit were observed in the dispersed asphalt phase of the modified WEABs. Sasobit decreased the size of asphalt particles in the continuous epoxy phase. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) with 0.2, 0.5, and 1.0 wt% loading was used to modify warm‐mix epoxy asphalt binders (WEABs). The thermal stability, structure of GO, rotational viscosity‐curing time performance, dynamic moduli, glass transitions, damping ability, mechanical performance, and phase‐separated morphology of GO/epoxy asphalt composites were investigated in the laboratory. GO significantly enhanced the thermal stability of the pure WEAB. X‐ray scattering analysis revealed that GO layers were delaminated in the epoxy asphalt binder. GO accelerated the cure reaction of the pure WEAB and thus resulted in higher rotational viscosity of GO/epoxy asphalt composites. Furthermore, the viscosity of the modified WEABs slightly increased in the GO content. GO increased the dynamic moduli and Tgs of both epoxy and asphalt for the pure WEAB. However, the damping ability of GO/epoxy asphalt composites was similar to that of the pure WEAB. Confocal microscopy observations revealed that GO was dispersed in both asphalt and epoxy phases of the phase‐separated WEAB. The asphalt domains in the continuous epoxy phase became more spherical and uniform with the existence of GO. Moreover, the dispersion of epoxy in the discontinuous asphalt phase became more evident. The mechanical properties of the pure WEAB were greatly improved with the addition of GO. The tensile toughness and strength of the pure WEAB increased by 31% and 33%, respectively, with the addition of 0.2 wt% GO. [ABSTRACT FROM AUTHOR]

Epoxy asphalt bond coat (EABC) has been widely used as a bonding layer in the construction of orthotropic steel deck bridges. To withstand the vibration of the steel deck, EABC needs to have strong bonding strength. In present article, sodium montmorillonite (Mt) was used to reinforce the neat EABC. The morphology and properties of EABC/Mt nanocomposites were characterized by scanning electron microscopy, X‐ray diffraction, Brookfield rotational viscometer, dynamic mechanical analysis, thermogravimetric analysis, automatic adhesion tester, and universal testing machine. No intercalation structure formed in the EABC/Mt nanocomposites. Mt dispersed uniformly in the EABC matrix. The inclusion of Mt increased the viscosity of the neat EABC in the initial stage of chemical reaction. Whereas, in the later curing stage, the viscosity of the neat EABC was higher than those of EABC/Mt nanocomposites. The presence of Mt slightly reduced the glass transition temperature of the neat EABC. The damping performance of the neat EABC was improved with the inclusion of 1 wt% Mt. Mt had a marginal effect on the thermal stability of the neat EABC. The incorporation of Mt significantly enhanced the mechanical properties of the neat EABC. The tensile strength and toughness of the neat EABC increased by 30% and 26%, respectively, with the inclusion of 3 wt% Mt. The existence of Mt greatly enhanced adhesion strength of the neat EABC. The lap‐shear adhesion strength and pull‐off adhesion strength of the EABC nanocomposite with 5 wt% Mt were 33% and 29% higher than those of the neat EABC. [ABSTRACT FROM AUTHOR]

Highlights • Sasobit modified epoxy asphalt rubber (EAR) has been developed. • The addition of Sasobit lowers the viscosity and glass transition temperature of the neat EAR. • The inclusion of Sasobit increases the number of spherical AR particles in the continuous epoxy phase. • The mechanical properties of the neat EAR are enhanced with the addition 1 wt% Sasobit. Abstract The utilization of crumb rubber to produce asphalt rubber (AR) for asphalt mixture pavement has been proven to be an economical and environmental way for the disposal of waste tires. As one of the most significant thermosetting polymer modified asphalt with prominent performances, epoxy asphalt (EA) has been widely used on the pavement of steel bridge decks. In present study, the mixture of epoxy oligomer and curing agent was incorporated into AR to prepare epoxy asphalt rubber (EAR). To lower the viscosity of AR, a WMA additive, Sasobit was introduced into AR to prepare Sasobit modified EARs. The effects of Sasobit on the rotational viscosity, glass transition temperature (T g), damping performance, mechanical properties and phase-separated morphology of the neat EAR were investigated. The inclusion of Sasobit significantly decreased the viscosity of the neat EAR during the whole curing process and prolonged the operational lifetime for asphalt mixture pavement. The addition of Sasobit slightly decreased the T g of the neat EAR. The T g of Sasobit modified EARs decreased with WMA additive content increasing. Meanwhile, the presence of Sasobit improved the damping properties of the neat EAR. The existence of Sasobit enhanced the mechanical properties of the neat EAR at lower WMA additive concentration. The mechanical properties of Sasobit modified EARs decreased with increasing WMA additive content. Morphological observations revealed that the phase-separated microstructures of the neat EAR consisted of the dispersed spherical and co-continuous AR particles and the continuous epoxy phase. The existence of Sasobit decreased the number of co-continuous AR particles in the epoxy matrix. In addition, the number of co-continuous AR particles decreased with increasing WMA additive content. The presence of Sasobit decreased the average diameter of the dispersed AR particles and area fraction of AR domains in the neat EAR. [ABSTRACT FROM AUTHOR]

As one of polymer modified asphalts (PMAs), epoxy asphalt (EA) has been extensively used in the pavement of steel bridge deck due to its excellent performances. Ethylene vinyl acetate copolymer (EVA) is one of most used polymer modifiers in PMAs. EA/EVA blends were prepared with the addition of EVA in asphalts. The effects of EVA on the morphology evolution of EA were investigated by laser scanning confocal microscopy (LSCM) and scanning electron microscopy (SEM). Furthermore, the rotational viscosity, thermal stability and mechanical properties of EA/EVA blends were studied. LSCM observed that epoxy resin was the continuous phase and EVA-asphalt was the disperse phase in EA/EVA blends. The presence of epoxy crosslinking network destroyed the physical interaction between EVA and asphalts. Both LSCM and SEM observations found that smaller and well-distributed EVA-asphalt particles formed in EA/EVA blends with lower EVA loadings. However, EVA-asphalt particles distributed inhomogeneously in the blends with higher EVA loadings. The addition of EVA increased the viscosity of the neat EA. Moreover, the presence of EVA improved both thermal stability and mechanical properties of the neat EA. [ABSTRACT FROM AUTHOR]

• Waste cooking oil (WCO) modified epoxy asphalt binder (EAB) has been developed. • WCO lowers the viscosity and thus extends the construction time of the neat EAB. • Phase inversion in WEAB occurs when 6 wt% WCO is added. • WCO improves the low-temperature performance of the neat EAB. • WCO enhances the damping properties and thermal stability of the neat EAB. Waste cooking oil (WCO) was used as a warm mix asphalt (WMA) additive to modify warm-mix asphalt binder (WEAB) with the expectation of lowering the viscosity and prolonging the construction time of the binder. The viscosity, phase separation, viscoelasticity, thermostability and mechanical properties of WCO modified WEABs were studied and compared with the neat WEAB. WCO significantly reduced the WEAB's viscosity and extended the construction time of the neat WEAB. Moreover, the reducing and prolonging effects increased with the WCO content. Phase-inverted microstructure and secondary phase separation formed in the modified WEAB with 6 wt% WCO. The inclusion of WCO improved the low-temperature performance of the neat WEAB. The damping behavior and thermostability of the neat WEAB were improved with the inclusion of WCO. The presence of WCO increased the elongation at break of the neat WEAB when the waste oil content was lower than 4 wt%. [ABSTRACT FROM AUTHOR]