界面超分子交联提高柔性、可拉伸和磁性Fe_(3)O_(4)@Ti_(3)C_(2)Tx/弹性体的机械和电磁屏蔽性能

Flexible,stretchable and magnetic Fe_(3)O_(4)@Ti_(3)C_(2)Tx/elastomer with supramolecular interfacial crosslinking for enhancing mechanical and electromagnetic interference shielding performance

电磁干扰和辐射无处不在,可能对电子设备的正常运行和人体健康造成危害.MXene具有出色的金属导电性和可调的表面化学,在屏蔽材料的制备中极具吸引力.本文通过结构设计和界面调控,制备了具有隔离网络结构的柔性Fe_(3)O_(4)@Ti_(3)C_(2)Tx MXene/3,4-二羟基苯基乙酸(DOPAC)-环氧化天然橡胶(ENR)弹性体(FMDE).Fe_(3)O_(4)与DOPAC配体分子之间的金属-配体配位交联提供了强大的界面相互作用,从而显著增强复合材料的机械性能.与Ti_(3)C_(2)Tx/ENR弹性体相比,FMDE的最大拉伸强度和韧性分别提高了~306%和~475%.此外,借助ENR胶乳的体积排斥效应构建的3D隔离导电网络,以及引入的磁性Fe_(3)O_(4)纳米颗粒有效地改善了FMDE的电磁屏蔽性能,且证实了FMDE在反复弯曲拉伸后仍具有稳定的电磁屏蔽能力.

Electromagnetic interference(EMI)and radiation of electronic devices are ubiquitous,which are potentially hazardous to the normal operation of electronic equipment and human health.MXenes are extremely attractive in the preparation of EMI shielding materials due to their excellent metallic conductivity and tunable surface chemistry.Herein,by virtue of the designed nanostructure and regulation of interface interactions,we fabricated flexible Fe_(3)O_(4)@Ti_(3)C_(2)Tx MXene/3,4-dihydroxyphenylacetic acid(DOPAC)-epoxidized natural rubber(ENR)elastomers(FMDE)with 3D segregated interconnected structures.The elaborately designed metalligand coordination crosslinking between Fe_(3)O_(4)nanoparticles and DOPAC ligand molecules provides strong interfacial interactions,resulting in significantly reinforced mechanical properties.Compared with Ti_(3)C_(2)Tx/ENR elastomers,the maximum tensile strength and toughness of FMDE are elevadted by~306%and 475%,respectively.Moreover,the 3D segregated conductive network constructed by Fe_(3)O_(4)@Ti_(3)C_(2)Tx nanoflakes resulted from volume exclusion effect of ENR latex and the introduction of magnetic Fe_(3)O_(4)nanoparticles with enhanced electromagnetic wave absorption greatly improved the EMI shielding performance of FMDE,exhibiting an excellent EMI shielding effectiveness of up to 58 dB in the X band(8.2–12.4 GHz)and stable EMI shielding capability during repeated deformations.This work provides a promising strategy for the design and manufacture of novel flexible EMI shielding materials.