Development of composite bio-oil regenerant and its effects on chemical constituents of long-term aged asphalt
As a kind of waste material in the production chain of plant oleic acid,vegetable asphalt has similar color and viscosity with asphalt.However,when vegetable asphalt is used as a regenerant alone,its high viscosity leads to poor permeability.Epoxidized soybean oil(ESO)is as an industrial plasticizer,and its low viscosity can reduce the viscosity of vegetable asphalt.To develop a new type of sustainable composite bio-oil regenerant product and under-stand its rejuvenation effect on the chemical constituents of long-term aged asphalt,the castor oil vegetable asphalt(COA)was selected to react with ESO for preparing the composite bio-oil regenerant.The optimal ratio of COA to ESO in the composite bio-oil regenerant was determined.The in-situ dynamic chemical reaction mechanism between COA and ESO,as well as the changes in chemical constituents of recycled asphalt were characterized.Results indicate that the mass ratio of COA to ESO is 1:3 in the prepared composite bio-oil regenerant.When the content of composite bio-oil regenerant agent is 8％,it has the best rejuvenating effect on the long-term aged asphalt.The composite bio-oil can restore the basic physical properties of aged asphalt to its original level,and the chemical reaction between COA and ESO can improve the viscosity of recycled asphalt,but reduces the ductility at low temperature.When COA and ESO are mixed at 80 ℃,the epoxide group in ESO and the carboxyl group in COA undergo the ring-opening conden-sation reaction to produce hydroxy-lipid.These continuous chemical reactions are one of the main reasons for the chan-ges in the basic properties of recycled asphalt,and the developed composite bio-oil regenerant can be prepared at any time.The performance recovery of long-term aged asphalt mainly depends on the physical fusion with the composite bio-oil regenerant.The composite bio-oil can reduce the content of carbonyl group in the aged asphalt,but cannot re-duce the content of sulfoxide group.This study provides a new kind of composite bio-oil regenerant for long-term aged asphalt,as well as reveals its effects on the chemical constituents of long-term aged asphalt and rejuvenation action.
composite bio-oilvegetable asphaltepoxidized soybean oilin-situ dynamic chemical reactionaged as-phaltrecycled asphalt
国家科技期刊平台
NSTL
万方数据
维普
