Performance Of Fireproof And Antibacterial Waterborne Epoxy Resins Synergistically Improved By Functionalized Graphene

With the development of social science and economy,the coating used in high-rise buildings and interior decoration is required to possess the multifunctionality,such as anti-corrosion,fireproof and antibacterial coatings.In this paper,the waterborne epoxy resin with water as the medium was prepared from bio-based raw materials,it did not contain toxic volatile organic compounds such as formaldehyde,benzene and glycol ether,and was healthy and environmentally friendly.The hydrophilic graphene was easily and efficiently prepared by natural arabic gum and one step,which high thermal stability,excellent barrier property,chemical inertness and good mechanical properties may endow waterborne epoxy composites with the improved mechanical,fireproof and anticorrosive properties.(1)The waterborne bisphenol A epoxy resin emulsion(WE51)was successfully prepared by hydrophilic modification and self-emulsification,where the hydrophilic graphene(CFG)modified by arabia gum was introduced,followed by curing with long-chain aliphatic amine(BC919)to obtain nano-reinforced waterborne epoxy composite films(CFG/WE51/BC919).When the loading of CFG was 0.15 wt%,the tensile modulus of the composite films was increased from 83.1 MPa of WE51/BC919 to 220.5 MPa,the tensile strength was increased from 2.7 MPa to 4.5 MPa,and the elongation at break was increased from 70.8%to 78.0%.Compared with WE51/BC919,T_gof CFG-0.15/WE51/BC919 composite films was increased from 63.1 ? to 72.8 ?,and the storage modulus at 30 ? was increased from 0.53 GPa to1.83 GPa.In addition,the adhesion of CFG-0.15/WE51/BC919 composite coating was increased from 1.70 MPa to 2.48 MPa,the water resistance period was prolonged from 2 days to 3 days,and the salt and alkali resistance period was prolonged from 3 days to 5 days.(2)A bio-based flame-retarded epoxy prepolymer(1E,1'E)-N,N'-(methylene bis(4,1-phenylene))bis(1-(3,4-bis(ethylene oxide-2-methoxy)phenyl)methylimine)(PDE)containing Schiff base structure was synthesized by the reaction of epichlorohydrin and the Schiff base intermediate,which was synthesized from protocatechuic aldehyde(PH)and4,4-diaminodiphenylmethane(DDM).The bio-based waterborne epoxy emulsion(WPDE)was prepared by hydrophilic modification and self-emulsification.CFG was introduced into the WPDE emulsion system,and CFG/WPDE/BC919 composite films were prepared after the curing reaction with BC919.Compared with those of WE51/BC919,the char residue(Y_C700)at 700 ? was increased by 191%,total heat release(THR)and total smoke production(TSP)of WPDE/BC919 were decreased by 25.4%and 18.2%,respectively,and there were almost no surviving Escherichia coli and Staphylococcus aureus on the surface,probablly due to the existence of Schiff base structure.When the loading of CFG was 0.20 wt%,the tensile modulus of CFG-0.20/WPDE/BC919 composite film was increased from 306.0 MPa of WPDE/BC919 to 654.2 MPa,the tensile strength was increased from 7.6 MPa to 10.0 MPa,and the elongation at break was increased from 34.4%to 69.6%.The T_gwas increased from79.5 ? to 88.6 ?,and the storage modulus at 30 ? was increased from 0.68 GPa to 2.42GPa.