Investigation on constitution of electrical conductive adhesives fitting for UV-thermal dual curing

In order to meet the requirements of environment protection and energy conservation, we propose to prepare electrical conductive adhesives (ECAs) fitting for UV-thermal dual curing and to investigate the constitution of the ECAs. Based on the determination of the mixture ratio of epoxy resin-44 (E-44) and unsaturated polyester resin (UP), the dosage of 3-Amino-propyl-triethoxy-silane (KH-550), thinner, thermal curing agent, accelerating agent, light-initiator agent, and the conductive filler of the ECAs was determined. The prepared films after UV-thermal dual curing were analyzed by Fourier transform infrared spectrometer and thermogravimetric analyzer to characterize their constitution and thermal properties. The best prescription of ECAs was obtained as follows: the ratio of E-44 and UP is 0.5:1, KH-550 is 6%, thinner is 8%, thermal curing agent is 7.5%, accelerating agent is 7.5%, light-initiator agent is 6%, and the conductive filler is 60%. Under these conditions, the prepared ECAs have cross-linked net structure and good thermal stability. Their properties are applicable as follows: the hardness is 6H; the tensile strength is 95.12 MPa; the volume resistivity is 4.75 Ω cm; the gel content is 93.37%; the water absorption ratio is 5.81%; and the stability is more than 180 days.