Zheng Liu, Xiaoli Fan, Junliang Zhang, Lixin Chen, Yusheng Tang*, Jie Kong and Junwei Gu*. PBO fibers/ fluorine-containing liquid crystal compound modified cyanate ester wave-transparent laminated composites with excellent mechanical and flame retardance properties. Journal of Materials Science & Technology, 2023, 152: 16-29. 2021IF=10.319.（1區(qū)材料科學(xué)Top期刊，中國(guó)科技期刊卓越行動(dòng)計(jì)劃-重點(diǎn)類期刊項(xiàng)目，2021中國(guó)最具國(guó)際影響力學(xué)術(shù)期刊）
https://doi.org/10.1016/j.jmst.2023.01.007
Abstract
Bisphenol A dicyanate ester resins modified by fluorine-containing liquid crystal compound (LCFE) are applied as polymer matrix (LCFE-BADCy), poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers as reinforcements, and fluorine/adamantane PBO precursor (preFABPBO) as interfacial compatibilizer to prepare the corresponding PBO fibers/FABPBO/LCFE-BADCy wave-transparent laminated composites. LCFE could improve the order degree of BADCy cured network, in favor of enhancing the wave-transparent performance, mechanical properties, and intrinsic thermal conductivity. The dielectric constant and dielectric loss of PBO fibers/FABPBO/LCFE-BADCy composites are highly temperature (25~200oC) and frequency (104~107 Hz and 8.2~12.4 GHz) stable with the value of 2.49 and 0.003 under 106 Hz at 25oC, and the corresponding wave transmission efficiency is 95.0%, higher than that of 92.5% for PBO fibers/BADCy composites. The interlamellar shear strength and flexural strength are respectively 50.7 MPa and 682.5 MPa, 38.1% and 16.2% higher than those of PBO fibers/BADCy composites. Besides, the volume resistivity, breakdown voltage, heat resistance index, glass transition temperature, flame retardant grade, and ultimate oxygen index of PBO fibers/FABPBO/LCFE-BADCy composites are respectively 5.3×1015 Ω·cm, 29.75 kV/mm, 217.2oC, 245.7oC, V-1 grade, and 33.6%, expected to be performed as a new generation of “l(fā)ight weight/loading/wave-transparent” electromagnetic window materials in advanced military weapons and civil communication base station.
以含氟液晶環(huán)氧化合物（LCFE）改性的雙酚A氰酸酯（LCFE-BADCy）樹脂為基體、聚對(duì)苯撐苯并二噁唑（PBO）纖維為增強(qiáng)體、含氟金剛烷PBO前驅(qū)體（preFABPBO）為界面相容劑，經(jīng)高溫模壓制備PBO纖維/FABPBO/LCFE-BADCy層壓透波復(fù)合材料。LCFE的引入提升了BADCy樹脂固化網(wǎng)絡(luò)的有序性，同步提升了LCFE-BADCy樹脂的透波性能、力學(xué)性能和本體導(dǎo)熱性能。PBO纖維/FABPBO/LCFE-BADCy層壓透波復(fù)合材料的介電常數(shù)和介電損耗角正切值分別為2.49和0.003（106 Hz，25oC），相應(yīng)的理論透波率為95.0%，高于PBO纖維/BADCy（92.5%），在較寬溫度（25~200oC）和頻率范圍內(nèi)（104~107 Hz和8.2~12.4 GHz）均具有優(yōu)異穩(wěn)定性；且在高頻段下具有較低的插入相位移，能夠保證電磁信號(hào)的高效和高保真?zhèn)鬏敚黄鋵娱g剪切強(qiáng)度（ILSS）和彎曲強(qiáng)度分別為50.7 MPa和682.5 MPa，較PBO纖維/BADCy的36.7 MPa和587.4 MPa分別提升了38.1%和16.2%。PBO纖維/FABPBO/LCFE-BADCy層壓透波復(fù)合材料的體積電阻率、擊穿電壓、耐熱指數(shù)、玻璃化轉(zhuǎn)變溫度、阻燃等級(jí)和極限氧指數(shù)分別為5.3×1015 Ω·cm、29.75 kV/mm、217.2oC、245.7oC、V-1級(jí)和33.6%。本文制備的層壓復(fù)合材料兼具優(yōu)異的透波性能、力學(xué)性能、絕緣性能、耐熱性能、耐環(huán)境老化性能和阻燃性能，有望作為新一代“輕量/承載/透波”一體化電磁窗口材料在新型軍用武器裝備和民用通信基站獲得更廣泛的應(yīng)用。
論文亮點(diǎn)
1. LCFE的共聚引入提升了BADCy樹脂固化網(wǎng)絡(luò)的有序性，同步提升了LCFE-BADCy樹脂的透波性能、力學(xué)性能和本體導(dǎo)熱性能。
2. PBO纖維/FABPBO/LCFE-BADCy層壓透波復(fù)合材料的理論透波率達(dá)95.0%，明顯優(yōu)于PBO纖維/BADCy的92.5%，且具有優(yōu)異溫度和頻率穩(wěn)定性。
3. PBO纖維/FABPBO/LCFE-BADCy層壓透波復(fù)合材料的ILSS和彎曲強(qiáng)度較PBO纖維/BADCy的ILSS（36.7 MPa）和彎曲強(qiáng)度（587.4 MPa）分別提升了38.1%和16.2%。
4. PBO纖維/FABPBO/LCFE-BADCy層壓透波復(fù)合材料的體積電阻率、擊穿電壓、耐熱指數(shù)、玻璃化轉(zhuǎn)變溫度、阻燃等級(jí)和極限氧指數(shù)分別為5.3×1015 Ω·cm、29.75 kV/mm、217.2oC、245.7oC、V-1級(jí)和33.6%。