Lei Wang, Zhonglei Ma, Yali Zhang, Hua Qiu*, Kunpeng Ruan and Junwei Gu*. Mechanically Strong and Folding-Endurance Ti3C2Tx MXene/PBO Nanofibers Films for Efficient EMI Shielding and Thermal Management. Carbon Energy, 2022, 10.1002/cey2.174. 2021即時因子19.741.（中國科技期刊卓越行動計劃高起點新刊）
https://doi.org/10.1002/cey2.174
Abstract
Electromagnetic interference (EMI) shielding materials with excellent flexibility & mechanical properties, and outstanding thermal conductivity have become a research hotspot in functional composites. In this work, the“sol-gel-film conversion technique” is used to assemble polyetherimide functionalized Ti3C2Tx nanosheets (f-Ti3C2Tx) with poly(p-phenylene-2,6-benzobisoxazole) (PBO) nanofibers (PNFs), followed by dialysis and vacuum drying to prepare the f-Ti3C2Tx/PNFs films with lamellar structures. When the loadings of f-Ti3C2Tx is 70 wt%, the f-Ti3C2Tx/PNFs film presents the optimal comprehensive properties, with EMI shielding effectiveness (SE) of 35 dB and specific SE/thickness ((SSE, SE/density)/t) of 8211 dB·cm2/g, tensile strength of 125.1 MPa, in-plane thermal conductivity coefficient of 5.82 W/(m·K), and electrical conductivity of 1943 S/m. After repeated folding for 10000 cycles, the EMI SE and tensile strength of f-Ti3C2Tx/PNFs films still maintain at 33.4 dB and 116.1 MPa, respectively. Additionally, f-Ti3C2Tx/PNFs film also shows excellent thermal stability, flame retardancy, and structural stability. It would provide a novel method for the design and fabrication of multifunctional composite films, and greatly expand the applications of MXene and PNFs-based composites in the fields of EMI shielding and thermal management.
兼具柔性、超高力學(xué)強度和優(yōu)異導(dǎo)熱性能的電磁屏蔽材料已成為功能復(fù)合材料領(lǐng)域的研究熱點和重要組成部分。本文通過“溶膠-凝膠-薄膜轉(zhuǎn)化技術(shù)”將聚醚酰亞胺功能化的Ti3C2Tx納米片（f-Ti3C2Tx）與poly(p-phenylene-2,6-benzobisoxazole，PEI)納米纖維（PNFs）復(fù)合制備f-Ti3C2Tx/PNFs有機凝膠，再通過溶劑置換并真空干燥制得層狀結(jié)構(gòu)的f-Ti3C2Tx/PNFs薄膜。當(dāng)f-Ti3C2Tx納米片用量為70 wt%時，f-Ti3C2Tx/PNFs薄膜具有最佳的綜合性能，其屏蔽效能（EMI SE）和比屏蔽效能/厚度（（SSE，SE/密度）/t）分別為35 dB和8211 dB·cm2/g，拉伸強度、面內(nèi)導(dǎo)熱系數(shù)（λ//）和電導(dǎo)率（σ）分別為125.1 MPa、5.82 W/(m·K)和1943 S/m；折疊10000多次后其EMI SE和拉伸強度仍維持在33 dB和116.1 MPa。f-Ti3C2Tx/PNFs薄膜同時具有卓越的熱穩(wěn)定性（800oC退火后的質(zhì)量損失僅為18.7 wt%）、優(yōu)異的阻燃性能（酒精燈灼燒下無任何火焰）和結(jié)構(gòu)穩(wěn)定性（水中超聲1 hr或浸泡72 hrs后無任何結(jié)構(gòu)破壞）。這種具有優(yōu)異λ、超高力學(xué)性能、卓越屏蔽性能、出色阻燃性能和耐疲勞性能的f-Ti3C2Tx/PNFs薄膜將為多功能復(fù)合薄膜的設(shè)計研發(fā)提供一定的借鑒意義，并極大地拓展MXene基納米復(fù)合材料以及PNFs基納米復(fù)合材料在電磁屏蔽和熱管理領(lǐng)域中的應(yīng)用。