[J Mater Sci Technol]Intrinsic high thermal conductive liquid crystal epoxy film simultaneously combining with excellent intrinsic self-healing performance
作者：Xutong Yang, Xiao Zhong, Junliang Zhang and Junwei Gu*
關(guān)鍵字：thermal conductive, liquid crystal
論文來源：期刊
發(fā)表時(shí)間：2020年
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-phenylphenol, 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. 1H NMR and FTIR show that S-LCE and LCEF have been successfully prepared. S-LCE presents nematic liquid crystal from room temperature to 160°C. 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, respectively, much higher than that of general bisphenol A epoxy resin (E-51, λ⊥ of 0.19 W/mK and λ∥ of 0.65 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°C) and good thermal stability (THRI of 148.5°C). Simultaneously, LCEF has good transparency, flexibility, and tailorability, expected to be utilized in the fields of flexible electronic devices and intelligent structures.以2,2-二羥甲基丙酸、4-苯基苯酚和環(huán)氧氯丙烷為主要原料合成了一種基于聯(lián)苯介晶基元的側(cè)鏈型液晶環(huán)氧（S-LCE），再通過硫醇-環(huán)氧親核開環(huán)反應(yīng)配合涂膜成型工藝制備了一種基于酯交換反應(yīng)實(shí)現(xiàn)自修復(fù)功能的本征型高導(dǎo)熱液晶環(huán)氧膜（LCEF）。核磁共振氫譜（1H NMR）和紅外光譜（FTIR）表明S-LCE及LCEF均已成功合成；S-LCE表現(xiàn)為向列相液晶，其液晶區(qū)間為常溫～160oC；LCEF仍保持向列相液晶性，且表現(xiàn)出優(yōu)異的本體導(dǎo)熱性能和自修復(fù)功能；其垂直方向（λ⊥）和平行方向（λ∥）的導(dǎo)熱系數(shù)分別為0.33 W/mK和1.52 W/mK，遠(yuǎn)高于通用雙酚A環(huán)氧樹脂（E-51）的λ⊥（0.19 W/mK）和λ∥（0.65 W/mK）；LCEF的拉伸強(qiáng)度為10.6 MPa，經(jīng)1次和4次修復(fù)后的拉伸強(qiáng)度分別保持在90.6 %和61.3%；此外，LCEF表現(xiàn)出較寬的使用溫度范圍（-9.8～251oC）和較好的熱穩(wěn)定性（耐熱指數(shù)，THRI為148.5oC）；同時(shí)，LCEF還具有較好的透明性、柔韌性和可裁剪性，有望在柔性電子器件和智能結(jié)構(gòu)等領(lǐng)域得到應(yīng)用。