Intrinsic high thermal conductive liquid crystal epoxy film simultaneously combining with excellent intrinsic self-healing performance

摘要

One kind of side chain liquid crystal epoxy(S-LCE) based on biphenyl mesomorphic unit is synthesized from 2,2-bis(hydroxymethyl)propionic acid,4-phenyl phenol,and epichlorohydrin.And the intrinsic thermal conductive liquid crystal epoxy film(LCEF) simultaneously combining with intrinsic self-healing performance is then prepared via thiol-epoxide nucleophilic ring-opening reaction and coating method.1 H NMR and FTIR show that S-LCE and LCEF have been successfully prepared.S-LCE presents nematic liquid crystal from room temperature to 160℃.LCEF maintains nematic liquid crystal performance and shows highly intrinsic thermal conductivity & excellent self-healing performance.Thermal conductivity coefficient(λ)values in vertical direction(λ⊥)and parallel direction(λ‖)of LCEF are 0.33 and 1.25 W/mK,re spectively,much higher than that of general bisphenol A epoxy resin(E-51,λ⊥ of 0.19 W/mK and λ‖ of0.65 W/mK).Tensile strength of LCEF is 10.6 MPa,which can maintain at 90.6 % and 61.3 % after one and four cycles of self-healing behavior,respectively.In addition,LCEF presents a wide service temperature range(-9.8-251℃) and good thermal stability(THRI of 148.5℃).Simultaneously,LCEF has good transparency,flexibility,and tailorability,expected to be utilized in the fields of flexible electronic devices and intelligent structures.