In this paper,the specimens of polymer-cement composites after 1 d,7 d,15 d,and 30 d aging without aging and UV aging are subjected to fixed extension test and tensile test.By observing the mode of the composite in th...In this paper,the specimens of polymer-cement composites after 1 d,7 d,15 d,and 30 d aging without aging and UV aging are subjected to fixed extension test and tensile test.By observing the mode of the composite in the fixed-elongation test,and measuring the elastic recovery rate,tensile strength,elongation at break,peak tensile strain,tensile toughness and pre-peak tensile toughness of the composite,the effects of UV aging on the bonding and the tensile properties of the composite were studied.And combining with scanning electron microscopy experiments,the micro-mechanism of the effect of ultraviolet aging on the properties of composite was analyzed.The results showed that the composite had a good bonding property,and no damage was observed after UV aging for 30 days.The UV aging increased the elastic recovery rate and peak tensile within a certain range.The elastic recovery rate and peak tensile strain of the composite increased by 6.60%and 23.55%respectively after UV aging for 15 days.Therefore,the UV aging could enhance the tensile property and the tensile energy consumption performance of the composite.The tensile strength of the composite increased by 65.36%after UV aging for 30 days.The tensile toughness and pre-peak tensile toughness of the composite were increased by 43.29%and 101.83%respectively after UV aging for 15 days.The elongation at break of composite decreased continuously after UV aging due to the photo-oxygen reaction,as well as secondary hydration reaction and cross-linking curing reaction of cement.展开更多
Self-cleaning surfaces are desirable in many engineering applications where low energy consumption,reusability and sustainability are of the biggest concerns.Inspired by the gecko’s unique ’dry selfcleaning’ hierar...Self-cleaning surfaces are desirable in many engineering applications where low energy consumption,reusability and sustainability are of the biggest concerns.Inspired by the gecko’s unique ’dry selfcleaning’ hierarchical structures.Here we fabricated artificial Fe304/PDMS composites that show robust self-cleaning capabilities.The enhanced adhesion performance is attributable to the decrease of PDMS polymerization degree and the load transfer between PDMS matrix and Fe304 magnetic particles.The self-cleaning surfaces showed up to 24.3% self-cleaning rate with as few as 4 steps.Simulation result indicated that the changing of cross linking between Fe304 and PDMS is the main reason for the enhanced self-cleaning surfaces.This work reveals an alternative route of making high-performance self-cleaning smart surfaces that are applicable in the textile industry,robotic locomotion/gripping technology,outerspace explorations and tissue engineering.展开更多
基金This research was funded by the National Natural Science Foundation of China,Grant No.51208507.
文摘In this paper,the specimens of polymer-cement composites after 1 d,7 d,15 d,and 30 d aging without aging and UV aging are subjected to fixed extension test and tensile test.By observing the mode of the composite in the fixed-elongation test,and measuring the elastic recovery rate,tensile strength,elongation at break,peak tensile strain,tensile toughness and pre-peak tensile toughness of the composite,the effects of UV aging on the bonding and the tensile properties of the composite were studied.And combining with scanning electron microscopy experiments,the micro-mechanism of the effect of ultraviolet aging on the properties of composite was analyzed.The results showed that the composite had a good bonding property,and no damage was observed after UV aging for 30 days.The UV aging increased the elastic recovery rate and peak tensile within a certain range.The elastic recovery rate and peak tensile strain of the composite increased by 6.60%and 23.55%respectively after UV aging for 15 days.Therefore,the UV aging could enhance the tensile property and the tensile energy consumption performance of the composite.The tensile strength of the composite increased by 65.36%after UV aging for 30 days.The tensile toughness and pre-peak tensile toughness of the composite were increased by 43.29%and 101.83%respectively after UV aging for 15 days.The elongation at break of composite decreased continuously after UV aging due to the photo-oxygen reaction,as well as secondary hydration reaction and cross-linking curing reaction of cement.
基金supported by the National Natural Science Foundation of China (Nos.51575528,51875577,51704243)Beijing Nova Program (No.Z171100001117058)+1 种基金Tribology Science Fund of State Key Laboratory of Tribology (No.SKLTKF16A06)Science Foundation of China University of Petroleum (No.2462019QNXZ02)
文摘Self-cleaning surfaces are desirable in many engineering applications where low energy consumption,reusability and sustainability are of the biggest concerns.Inspired by the gecko’s unique ’dry selfcleaning’ hierarchical structures.Here we fabricated artificial Fe304/PDMS composites that show robust self-cleaning capabilities.The enhanced adhesion performance is attributable to the decrease of PDMS polymerization degree and the load transfer between PDMS matrix and Fe304 magnetic particles.The self-cleaning surfaces showed up to 24.3% self-cleaning rate with as few as 4 steps.Simulation result indicated that the changing of cross linking between Fe304 and PDMS is the main reason for the enhanced self-cleaning surfaces.This work reveals an alternative route of making high-performance self-cleaning smart surfaces that are applicable in the textile industry,robotic locomotion/gripping technology,outerspace explorations and tissue engineering.
