Synthesis Of BPA-GA Phenolic Epoxy Resin And Its Preparation And Properties Of Conductive Adhesive

With the integration of electronic products,tin-lead solder can no longer meet the packaging needs of microelectronics.Conductive adhesives have the advantages of small bonding pitch and low curing temperature,and have a broad application prospect in the electronic packaging industry.The current conductive adhesive has poor toughness of the base resin,high volume resistivity,poor long-term storage stability and other issues.Therefore,the development of high-performance conductive adhesives for electronic packaging technology and the development of the entire electronics industry is of great significance.In this thesis,BPA-GA phenolic resin(bisphenol A glutaraldehyde phenolic resin)was synthesized by condensation reaction of BPA(bisphenol A)and GA(glutaraldehyde),and then nucleophilic substitution with ECH(epichlorohydrin)BPA-GA novolac epoxy resin(bisphenol A glutaraldehyde novolac epoxy resin)was synthesized by reaction,and BPA-GA novolac epoxy resin conductive adhesive(bisphenol A glutaraldehyde novolac epoxy resin conductive adhesive)was prepared.The bonding properties and electrical conductivity are discussed.The main studies are as follows:(1)BPA-GA phenolic resins were synthesized by a condensation reaction using BPA and GA as raw materials and n-butanol as solvent and NaOH as catalyst,BPA-GA phenolic resin was synthesized through polycondensation reaction.FT-IR,1H-NMR,GPC and elemental analysis were used for the compositional analysis,structural characterization and molecular weight determination of the products.The fluorescence properties and thermal stability of the BPA-GA phenolic resin were tested by FS and TGA,respectively.The laws of aldehyde-to-phenol ratio,NaOH dosage,n-butanol dosage,reaction temperature and reaction time on the solid content were investigated.On this basis,the BBD model in response surface analysis was used to optimize the synthesis process parameters of BPA-GA phenolic resin,and a quadratic regression equation for the solid content was established.The best process parameters were obtained:the phenolic ratio was 0.7:1,the reaction temperature was 95℃,the reaction time was 6 h,the amount of NaOH was 0.15 g,and the amount of n-butanol was 35 mL.Under these conditions,the solid content of BPA-GA phenolic resin was 77.39%.(2)BPA-GA phenolic epoxy resin was synthesized by nucleophilic substitution reaction using BPA-GA phenolic resin and ECH as raw material and TBAB as catalyst.Characterization of product structure by FT-IR,1H-NMR,GPC,elemental analysis.The fluorescence properties and thermal stability of the BPA-GA phenolic epoxy resin were tested by FS and TGA,respectively.The effects of etherification time,etherification temperature,TBAB dosage,ECH dosage,closed loop time,closed loop temperature,NaOH mass concentration and NaOH dosage factors on the epoxy value of BPA-GA phenolic epoxy resin were investigated.Optimisation of process parameters using orthogonal experiments.The best process parameters were obtained:etherification time was 3.5 h,etherification temperature was 110℃,TBAB dosage was 0.26 g,ECH dosage was 50 mL,loop closure time was 1 h,loop closure temperature was 65℃,NaOH mass concentration was 10%,NaOH dosage was 40 mL.Under these conditions,the epoxy value of BPA-GA phenolic epoxy resin was 0.6942.(3)BPA-GA phenolic epoxy resin,BDE(1,4-butanediol diglycidyl ether),MeHHPA(methyl hexahydrophthalic anhydride),DMP-30(2,4,6-tri(two)Methylaminomethyl phenol),10 μm silver powder,MWCNTs(multi-walled carbon nanotubes),KH-560 and AN1135 were used as raw materials to prepare BPA-GA phenolic epoxy resin conductive adhesive.The morphology of the product was characterized by SEM,and the thermal stability of the product was tested by TGA.The effects of curing temperature,curing time,m(resin):m(MeHHPA),silver powder addition,DMP-30 dosage,KH-560 content and MWCNTs addition on the performance of BPA-GA phenolic epoxy resin conductive adhesive were investigated.On this basis,the BBD model in response surface analysis was used to optimize the synthesis process parameters of BPA-GA phenolic epoxy resin conductive adhesive,and the quadratic regression equation for the tensile shear strength was established.The optimum conditions were obtained as follows:Obtained better process conditions:curing temperature was 130℃,curing time was 100 min,m(resin):m(MeHHPA)=100:40,silver powder content was 80%,DMP-30 content was 2.5%,KH-560 content was 1%,The content of MWCNTs was 3%,the content of BDE was 1%,the content of AN1135 was 1%.Under these conditions,the volume resistivity of the BPA-GA phenolic epoxy resin conductive adhesive was 0.28×10-3 Ω·cm,and the tensile shear strength was 22.8 MPa.