Wufeng Su

Bio: Wufeng Su is an academic researcher from Nanjing University. The author has contributed to research in topics: Epoxy & Dynamic mechanical analysis. The author has an hindex of 5, co-authored 7 publications receiving 64 citations.

Laboratory evaluation of warm-mix epoxy SBS modified asphalt binders containing Sasobit

Abstract: As the most popular thermoplastic and thermosetting polymers, styrene-butadiene-styrene triblock copolymer (SBS) and epoxy resin have been extensively applied in polymer modified bitumen. In this paper, epoxy SBS-modified asphalt (ESBA) containing high percentage of industrial SBS modified asphalt (SBA) was prepared. To lower the viscosity, an organic warm mix asphalt (WMA) additive, named Sasobit, was incorporated into SBA to prepare Sasobit modified ESBAs. The effect of Sasobit concentration on the morphology and performance of the neat ESBA was investigated. By adding Sasobit, the viscosity of the neat ESBA decreased and the construction time of the ESBA mixture was extending. Regarding the newly formed microstructural morphology, curly ribbon crystalline structures formed in Sasobit modified SBA. However, no crystalline structures were observed in the secondary SBA phase of Sasobit modified ESBAs. Sasobit disrupted the spherical phase-separated morphology of the neat ESBA. In terms of the Sasobit modified ESBAs, the co-continuous phase-separated morphology converted to phase-inverted morphology with the increase of the WMA additive concentration. Sasobit improved the low-temperature performance of the neat ESBA. The WMA additive weakened the damping properties of the neat ESBA. However, the low-temperature toughness and high-temperature stability of the neat ESBA were improved with the existence of Sasobit. The inclusion of 1.2 wt% Sasobit enhanced the elongation at break and toughness of the neat ESBA. Furthermore, Sasobit increased the Young's modulus of the neat ESBA.

Toughening of epoxy resin systems using core–shell rubber particles: a literature review

Abstract: Excellent thermal and mechanical properties and high chemical resistance with low shrinkage of epoxy resins open a wide window of various industrial applications, including coatings, paints, adhesive, etc. Despite their excellent properties, epoxy resins are brittle and have a low resistance to the initiation and growth of cracks. To overcome this drawback, different kinds of reinforcements, including liquid rubbers, core–shell rubber particles, dendritic polymers, block copolymers, thermoplastics, rigid particles, etc., have been used to improve the fracture toughness of epoxy resin systems. This paper briefly introduces each reinforcement separately and mainly presents an in-depth review of the progress of the last decade in the field of toughening of epoxy resins using core–shell rubber particles. This review paper also refers to the results of the research papers published on the effect these rubber particles on the mechanical properties of epoxy resins, as well as explains different toughening mechanisms of epoxy resins. Researchers first focused on the use of core–shell rubber particles containing different cores and shells. They then used core–shell rubber particles along with rigid fillers such as silica to offset the slight diminish in mechanical properties, as well as the glass transition temperature. In recent years, some research teams have used core–shell rubber particles and block copolymers simultaneously and have achieved fascinating results.