The goal of net zero carbon emissions is of a great concern to energy conservation and emission reduction.In aerospace and other industrial fields,one of main energy consumption forms is friction between motion pairs,...The goal of net zero carbon emissions is of a great concern to energy conservation and emission reduction.In aerospace and other industrial fields,one of main energy consumption forms is friction between motion pairs,although the energy consumption caused by equipment mass cannot be ignored.Therefore,ultra-low density self-lubricating composites with an interpenetrating polymer network(IPN)structure-liquid lubricant coupling mechanism are designed and prepared in this work to meet the pressing requirements of energy saving and emission reduction.The liquid lubricant is locked in situ into polyurethane acrylate(PUA)with IPN structures(IPN-PUA structures).The thermodynamic,mechanical,and tribological properties,as well as the comprehensive density-friction properties of the material with IPN-PUA structures were studied.After the liquid lubricant is locked into the IPN-PUA structure,the material possesses not only excellent self-lubricating properties but also good micro-mechanical properties,with a coefficient of friction(COF)of 0.0938,wear rate of 6.58×10^(−15) m^(3)/(N·m)and nanoindentation modulus of 4.5 GPa.Compared with other polymeric materials,such composite materials also possess an ultra-low density of 1.107 g/cm3,which contributes to their excellent versatile self-lubrication and low-density characteristics.展开更多
A homologous series of Schiff base esters, 6-methoxy-2-（2-hydroxy-4-alkanoyloxybenzylidenamino）benzothiazoles, compris- ing a benzothiazole moiety as the core was synthesized. All the members of this series exhibite...A homologous series of Schiff base esters, 6-methoxy-2-（2-hydroxy-4-alkanoyloxybenzylidenamino）benzothiazoles, compris- ing a benzothiazole moiety as the core was synthesized. All the members of this series exhibited an enantiotropic nematic phase. The azomethine linkage along with the lateral hydroxyl and terminal methoxyl groups were found to exert an effect on the mesomorphic properties. 2009 Sie Tiong Ha. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
基金financially supported by the Natural Science Foundation of Hebei Province of China(No.E2021203092)the Opening Foundation of State Key Laboratory of Tribology in Advanced Equipment(SKLT)at Tsinghua University(No.SKLTKF21B13)+1 种基金the National Natural Science Foundation of China(No.51905297)the Aviation Scientific Fund Project(No.20200045099001).
文摘The goal of net zero carbon emissions is of a great concern to energy conservation and emission reduction.In aerospace and other industrial fields,one of main energy consumption forms is friction between motion pairs,although the energy consumption caused by equipment mass cannot be ignored.Therefore,ultra-low density self-lubricating composites with an interpenetrating polymer network(IPN)structure-liquid lubricant coupling mechanism are designed and prepared in this work to meet the pressing requirements of energy saving and emission reduction.The liquid lubricant is locked in situ into polyurethane acrylate(PUA)with IPN structures(IPN-PUA structures).The thermodynamic,mechanical,and tribological properties,as well as the comprehensive density-friction properties of the material with IPN-PUA structures were studied.After the liquid lubricant is locked into the IPN-PUA structure,the material possesses not only excellent self-lubricating properties but also good micro-mechanical properties,with a coefficient of friction(COF)of 0.0938,wear rate of 6.58×10^(−15) m^(3)/(N·m)and nanoindentation modulus of 4.5 GPa.Compared with other polymeric materials,such composite materials also possess an ultra-low density of 1.107 g/cm3,which contributes to their excellent versatile self-lubrication and low-density characteristics.
基金Universiti Tunku Abdul Rahman(UTAR)for the research facilities andfinancial support(No.6202/K06)the Malaysian Toray Science Foundation(No.4359/000)
文摘A homologous series of Schiff base esters, 6-methoxy-2-（2-hydroxy-4-alkanoyloxybenzylidenamino）benzothiazoles, compris- ing a benzothiazole moiety as the core was synthesized. All the members of this series exhibited an enantiotropic nematic phase. The azomethine linkage along with the lateral hydroxyl and terminal methoxyl groups were found to exert an effect on the mesomorphic properties. 2009 Sie Tiong Ha. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
