Preparation And Properties Of Polymer Modified Deoiled Asphalt And Slurry Blends

Deoiled asphalt(DOA)is the extraction residue of solvent deasphalting process.It has high softening point,low penetration and high brittleness.Slurry is a component of the bottom of catalytic unit in refinery.It has low softening point and high penetration.DOA and slurry are limited in application because of their poor performance,resulting in low economic value.Using DOA and slurry as raw materials to produce asphalt raw materials for waterproofing materials by blending method can not only make better use of DOA and slurry resources,but also reduce the cost of polymer modified asphalt waterproofing materials,which is of great significance for the development of petrochemical and waterproofing industries.DOA/slurry blended asphalt was prepared from DOA and slurry,and the relationship between the four components of DOA/slurry blended asphalt and its physical properties was established.Then SBS,rubber powder and SBS/rubber powder composite modified DOA/slurry blended asphalt were prepared by melt blending method,and the effects of modifier content on the physical properties and microstructure of blended asphalt were studied.The anti-aging properties of different modified blended asphalts were studied by thermal-oxidative aging and ultraviolet aging tests,and were studied by Fourier transform infrared spectroscopy and fluorescence microscopy.Changes of chemical structure and micro-morphology of modified blended asphalt before and after aging.The main conclusions are as follows:(1)Using DOA and slurry as raw materials,asphalt raw materials for waterproofing materials can be prepared by adjusting method.When the DOA/slurry ratio is 3:7,the penetration of blended asphalt is 68 DMM and the softening point is 43 degree C.(2)The physical properties of blended asphalt are closely related to its component content.The results show that penetration,ductility and saturation,aromatics,softening point and viscosity are positively correlated with gum and asphaltene.Grey correlation analysis further shows that saturation and aromatics have great influence on low temperature performance of blended asphalt,while gum and asphalt have more obvious influence on high temperature performance.(3)The high and low temperature properties of DOA/slurry blended asphalt have been greatly improved by SBS,rubber powder and SBS/rubber powder composite modification.When the content of SBS is 12%,the softening point and low temperature flexibility of modified blended asphalt are 105 C and-25 C respectively;when the content of rubber powder is 24%,the softening point and low temperature flexibility of modified blended asphalt are 70 C and-16 C respectively;when 12% SBS and 24% rubber powder are combined,the softening point and low temperature flexibility of blended asphalt can reach 116 C and-33 C respectively.(4)Fluorescence microscopic images show that when SBS content is 12%,SBS in DOA/slurry blended asphalt changes from dispersed phase to continuous phase with network structure,which greatly improves the performance of SBS modified blended asphalt.Rubber powder swells mainly in modified blended asphalt,and changes from compact particle structure to relatively loose flocculent structure,which improves the properties of DOA/slurry blended asphalt.Yes.(5)Penetration and ductility of DOA/slurry blended asphalt decreased,softening point and viscosity increased,and low temperature flexibility became worse after long-term thermal-oxidative aging.Through SBS and rubber powder modification,aging can be inhibited to deteriorate the physical properties of blended asphalt,and the effect of SBS and rubber powder composite on the aging resistance of asphalt is more obvious.(6)After ultraviolet aging,the performance of DOA/slurry blended asphalt decreased significantly: residual penetration ratio and ductility retention rate were 36.4% and 13.5%,respectively.SBS and rubber powder can inhibit the deterioration of the properties of blended asphalt and obviously improve the anti-ultraviolet aging ability of blended asphalt.SBS/rubber powder composite modification further improves the anti-ultraviolet aging ability of blended asphalt.Residual penetration ratio and ductility retention rate reach 65.7% and 27.3%,respectively.(7)The fluorescence microscopic images showed that the polymer in SBS modified blended asphalt was degraded by aging,and the network structure was damaged,resulting in a significant reduction in the performance of modified blended asphalt.Infrared spectrum analysis showed that the oxidative reaction took place in the aging process of blended asphalt,the carbonyl and sulfoxide functional group index increased significantly,while the carbonyl and sulfoxide functional group index decreased significantly with the addition of SBS and rubber powder,which indicated that SBS and rubber powder could inhibit the aging of asphalt and improve the aging resistance of modified blended asphalt.