The pre-wetting of aggregate surface is a means to improve the interface performance of SBS modified asphalt and aggregate.The effect of pre-wetting technology on the interaction between SBS modified asphalt and aggre...The pre-wetting of aggregate surface is a means to improve the interface performance of SBS modified asphalt and aggregate.The effect of pre-wetting technology on the interaction between SBS modified asphalt and aggregate was analyzed by molecular dynamics simulation.The diffusion coefficient and concentration distribution of SBS modified asphalt on aggregate surface are included.The simulation results show that the diffusion coefficient of the aggregate surface of SBS modified asphalt is increased by 47.6%and 70.5%respectively after 110#asphalt and 130#asphalt are pre-wetted.The concentration distribution of SBS modified asphalt on the aggregate surface after pre-wetting is more uniform.According to the results of interface energy calculation,the interface energy of SBS modified bitumen and aggregate can be increased by about 5%after pre-wetting.According to the results of molecular dynamics simulation,the pre-wetting technology can effectively improve the interface workability of SBS modified bitumen and aggregate,so as to improve the interface performance.展开更多
Increasing environmental concerns about limiting harmful emissions has necessitated sulfur-and phosphorus-free green lubricant additives.Although boron-containing compounds have been widely investigated as green lubri...Increasing environmental concerns about limiting harmful emissions has necessitated sulfur-and phosphorus-free green lubricant additives.Although boron-containing compounds have been widely investigated as green lubricant additives,their macromolecular analogs have been rarely considered yet to develop environmentally friendly lubricant additives.In this work,a series of boron-containing copolymers have been synthesized by free-radical copolymerization of stearyl methacrylate and isopropenyl boronic acid pinacol ester with different feeding ratios(S_(n)-r-B_(m),n=1,m=1/3,1,2,3,5,9).The resulting copolymers of S_(n)-r-B_(m)(n=1,m=1/3,1,2,3,5)are readily dispersed in the PAO-10 base oil and form micelle-like aggregates with hydrodynamic diameters ranging from 9.7 to 52 nm.SRV-IV oscillating reciprocating tribological tests on ball-on-flat steel pairs show that compared with the base oil of PAO-10,the friction coefficients and wear volumes of the base oil solutions of S_(n)-r-B_(m)decrease considerably up to 62%and 97%,respectively.Moreover,the base oil solution of S_(1)-r-B_(1)exhibits an excellent load-bearing capacity of(850±100)N.These superior lubricating properties are due to the formation of protective tribofilms comprising S_(n)-r-B_(m),boron oxide,and iron oxide compounds on the lubricated steel surface.Therefore,the boron-containing copolymers can be regarded as a novel class of environmentally friendly lubricating oil macroadditives for efficient friction and wear reduction without sulfur and phosphorus elements.展开更多
基金Funded by the Research Funds of China University of Mining and Technology(No.102523215)。
文摘The pre-wetting of aggregate surface is a means to improve the interface performance of SBS modified asphalt and aggregate.The effect of pre-wetting technology on the interaction between SBS modified asphalt and aggregate was analyzed by molecular dynamics simulation.The diffusion coefficient and concentration distribution of SBS modified asphalt on aggregate surface are included.The simulation results show that the diffusion coefficient of the aggregate surface of SBS modified asphalt is increased by 47.6%and 70.5%respectively after 110#asphalt and 130#asphalt are pre-wetted.The concentration distribution of SBS modified asphalt on the aggregate surface after pre-wetting is more uniform.According to the results of interface energy calculation,the interface energy of SBS modified bitumen and aggregate can be increased by about 5%after pre-wetting.According to the results of molecular dynamics simulation,the pre-wetting technology can effectively improve the interface workability of SBS modified bitumen and aggregate,so as to improve the interface performance.
文摘Increasing environmental concerns about limiting harmful emissions has necessitated sulfur-and phosphorus-free green lubricant additives.Although boron-containing compounds have been widely investigated as green lubricant additives,their macromolecular analogs have been rarely considered yet to develop environmentally friendly lubricant additives.In this work,a series of boron-containing copolymers have been synthesized by free-radical copolymerization of stearyl methacrylate and isopropenyl boronic acid pinacol ester with different feeding ratios(S_(n)-r-B_(m),n=1,m=1/3,1,2,3,5,9).The resulting copolymers of S_(n)-r-B_(m)(n=1,m=1/3,1,2,3,5)are readily dispersed in the PAO-10 base oil and form micelle-like aggregates with hydrodynamic diameters ranging from 9.7 to 52 nm.SRV-IV oscillating reciprocating tribological tests on ball-on-flat steel pairs show that compared with the base oil of PAO-10,the friction coefficients and wear volumes of the base oil solutions of S_(n)-r-B_(m)decrease considerably up to 62%and 97%,respectively.Moreover,the base oil solution of S_(1)-r-B_(1)exhibits an excellent load-bearing capacity of(850±100)N.These superior lubricating properties are due to the formation of protective tribofilms comprising S_(n)-r-B_(m),boron oxide,and iron oxide compounds on the lubricated steel surface.Therefore,the boron-containing copolymers can be regarded as a novel class of environmentally friendly lubricating oil macroadditives for efficient friction and wear reduction without sulfur and phosphorus elements.