Facile preparation and application performance evaluation of SBS/C9 petroleum resin blends as modifier for high viscosity asphalt

•SBS/C9 petroleum resin blends (SPR) were prepared via a polymer alloying process.•The chemical structure of SPR and its modification effect on asphalt were studied.•The cost of SRP and conventional modifiers and high viscosity asphalt was compared.•SPR is a good modifier for high viscosity asphalt with high performance and low cost. To reduce the cost of high viscosity asphalt, SBS/C9 petroleum resin blends (SPR) were prepared via a simple one-pot polymer alloying process as modifiers for high viscosity asphalt in this study. The chemical characteristics of SRP and its modification effect on asphalt were studied and also compared with the traditional modifier (Tafpack-Super, abbreviated as TPS). Results show that SPR modifier contains more oxygen-containing functional groups than the TPS modifier. The molecular weight of SPR modifier is slightly higher but distributes over a wider range than that of the TPS modifier. Besides, its melting and crystallization temperatures of SPR modifier are lower than those of TPS modifier, thus SPR modifier has better compatibility with asphalt during production, making SPR easier to be dispersed in asphalt with smaller average particle size. Due to these reasons, SPR modifier has better modification effect on asphalt than traditional TPS modifier. Besides, the price of self-made SPR can be reduced to 29% of that of commercial TPS modifier, and the raw materials price of high viscosity asphalt with SPR modifier can reduce to 48.8% of that with TPS modifier. Therefore, SPR is a good modifier for the preparation of high viscosity asphalt with high performance and low cost.