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

Abstract

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.

Keywords:

• UV curing
• dual curing
• electrical conductive adhesive
• constitution