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The conductive adhesive is a high adhesive strength of the epoxy resin adhesive and the highly conductive silver powder particles subtly complex prepared from. Popular due to its green and non-toxic, low-cost, replace tin-lead solder, semiconductor packages, electronic components lead connections, repair the ideal choice for printed circuit board wiring, adhesive conductive composite materials, etc. . Epoxy adhesives are a class of high performance engineering adhesives, which consists of an epoxy resin substrate, a curing agent, a diluent, promoting agents and filler formulated. However, with the development of technology, the market, its requirements are no longer limited to the original performance, such as heat resistance, adhesive properties, such as the need for greater breakthroughs. Epoxy performance, such as: good adhesion properties, good electrical insulation properties, blending performance. However, due to its own low elongation, high brittleness, the adhesive member is intolerant fatigue should not be use in structural parts, the brittleness of the cured epoxy resin greatly limits their application. Polyimide (PI), in particular, is an aromatic polyimide having excellent abrasion resistance, heat resistance, radiation resistance and high dimensional stability, etc.. Modifying the epoxy resin with the polyimide can be integrated both the advantages obtained having good mechanical properties and bond strength, high temperature adhesive. With the introduction of reactive groups, polyimide unique features of concern. In recent years, at home and abroad for the adhesives containing active group reunion imide modified some research. Since this polyimide can be introduced through the reactive groups functional groups, to thereby prepare a functional polyimide adhesive to enhance the value of their potential application. The main topic is divided into six parts: (1) Preparation and characterization of the carboxyl group-containing polyimide monomer; (2) Preparation and performance testing of the carboxyl group-containing polyimide film and Research; (3) epoxy Preparation of adhesive; (4) containing a carboxy-the polyimide modified epoxy adhesive system developed; (5) containing carboxyl polyimide modified adhesive curing kinetics analysis; (6) containing the carboxyl polyimide conductive adhesives Preparation and performance testing. First, 3,5 - dihydroxy A benzoate (35DHBA), potassium carbonate (K2CO3) and quintozene (PCNB), raw materials, the reaction in toluene and N, N-dimethyl formamide (DMF) in a mixed solvent two nitro compounds by nucleophilic substitution reaction of 3,5 - bis (4 - nitrophenoxy)-benzoic acid (35BNPBA); using activated carbon, hydrazine hydrate, ferric chloride further reduction diamino was 35BAPBA. And the use of DSC, FT-IR absorption peak of the monomer melting point and features were characterized. Second synthesized 35BAPBA monomer, respectively and pyromellitic tetracarboxylic acid dianhydride (PMDA), 3,3 ', 4,4' - diphenylether tetracarboxylic dianhydride (ODPA), 3,3 ', 4,4 '- benzophenone tetracarboxylic dianhydride (BTDA), biphenyl dianhydride (BPDA) polymerization prepared the corresponding polyamic acid, and further thermal cyclization had corresponding polyimide film, and polyimide polyimide film, DSC, TGA, Fourier transform infrared, contact angle, water absorption, the mechanical properties of the test. Found that polyimide film has excellent overall performance. With 35BAPBA/ODPA-PI polyimide modified the ES216 type epoxy resin adhesives, prepared by mixing the epoxy glue, and its tensile shear strength, the gelation time, water absorption, thermal weight loss and other performance testing. The research results show that the the ES216 type 35BAPBA/ODPA-PI polyimide-modified epoxy resin adhesive has excellent overall performance. And its curing kinetics of the system apparent activation energy 72.5kJ/mol, the reaction order of 0.9. Join the 73% PA-1, conductive adhesive, homemade silver volume resistivity of the conductive adhesive tensile shear strength at room temperature storage system. A volume resistivity of 2.5 × 10-4Ω · cm; strength of 22.0MPa in humid and high-temperature environment, the volume resistivity of the conductive adhesive after curing, and tensile shear strength change is small, has excellent resistance to heat aging properties .
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