To enhance the wear resistance of graphene oxide(GO)nano-filled epoxy resin(EP)coatings with ex-cellent dispersion,GO were modified using a co-crosslinking strategy between polydopamine(PDA)and polyethyleneimine(PEI)t...To enhance the wear resistance of graphene oxide(GO)nano-filled epoxy resin(EP)coatings with ex-cellent dispersion,GO were modified using a co-crosslinking strategy between polydopamine(PDA)and polyethyleneimine(PEI)through an environmentally friendly,simple and low-cost process.High-density amino-branched PEI and highly adhesive PDA formed covalent bond cross-links with GO(PDA/PEI-GO)through the Michael addition and Schiffbase reactions.With the introduction of amino active sites,the PDA self-polymerization reaction time was significantly shorted from 24 to 6 h.The covalently cross-linked network increased the lamellar spacing of GO and enhanced the interfacial bonds between the PDA/PEI-GO lamellae and EP matrix.Due to the improved dispersion and surface activity of GO,the PDA/PEI-GO nano-filled EP coating exhibited excellent wear resistance.Reciprocating friction with GCr15 stainless steel ball,the average friction coefficient and wear rate of the coating were reduced by 31.9%and 62.7%,respectively,compared to the pure EP coating.In addition,the wear mechanism of the PDA/PEI-GO/EP coating changed from adhesive and fatigue wear to abrasive wear,and it maintained good wear resistance by forming a GO lubrication transfer film on the counterpart surface.Therefore,this study may provide a new strategy for improving the dispersion of graphene in wear-resistant polymer materials for practical applications.展开更多
基金This work was financially supported by the Shanxi Province Science and Technology Major Project for New Materials Tech-nology(No.20181102014)the Shanxi Province 1331 Project Key Innovation Team of Polymeric Functional New Materials,the Natural Science Foundation of Shanxi Province of China(No.20210302123036)the Program for the Excellent Young Aca-demic Leaders of Higher Learning Institutions of Shanxi Province.
文摘To enhance the wear resistance of graphene oxide(GO)nano-filled epoxy resin(EP)coatings with ex-cellent dispersion,GO were modified using a co-crosslinking strategy between polydopamine(PDA)and polyethyleneimine(PEI)through an environmentally friendly,simple and low-cost process.High-density amino-branched PEI and highly adhesive PDA formed covalent bond cross-links with GO(PDA/PEI-GO)through the Michael addition and Schiffbase reactions.With the introduction of amino active sites,the PDA self-polymerization reaction time was significantly shorted from 24 to 6 h.The covalently cross-linked network increased the lamellar spacing of GO and enhanced the interfacial bonds between the PDA/PEI-GO lamellae and EP matrix.Due to the improved dispersion and surface activity of GO,the PDA/PEI-GO nano-filled EP coating exhibited excellent wear resistance.Reciprocating friction with GCr15 stainless steel ball,the average friction coefficient and wear rate of the coating were reduced by 31.9%and 62.7%,respectively,compared to the pure EP coating.In addition,the wear mechanism of the PDA/PEI-GO/EP coating changed from adhesive and fatigue wear to abrasive wear,and it maintained good wear resistance by forming a GO lubrication transfer film on the counterpart surface.Therefore,this study may provide a new strategy for improving the dispersion of graphene in wear-resistant polymer materials for practical applications.
