Bionic Engineering Strategy for Preparing Flexible Carbon Paper From Waste Polypropylene: Excellent Electromagnetic
Minghang Yang1,2,3,4, Shuaining Zhou1,2,3,4, Yu Deng1,2,3,4
1State Key Laboratory of Fine Chemicals, Frontier Science Center For Smart Materials-Oriented Chemical Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, P. R. China.
Abstract:
Flexible paper-based carbon materials are considered an advantageous choice for meeting the intelligent requirements of electromagnetic interference (EMI) shielding materials. Inspired by nacre structures, an economical and efficient multifunctional polypropylene-based flexible carbon paper (PP-CP) was prepared in this study using recycled polypropylene (rPP) and waste pre-oxidized fibers as precursors. Based on the "heterogeneous swelling" effect of PP matrix during the liquid phase sulfonation process, a high-strength flexible interpenetrating network structure was constructed from PP-derived carbon and short-cut carbon fibers (SCF). A synergistic 3D conductive network formed by SCF and PP-derived microcracks resulted in a high electrical conductivity of 7735 S m- 1. The highest EMI shielding effectiveness (EMI SE) of 58.8 dB and thickness-averaged specific SE (SSE/t) of 6642 dB·cm2/g in the X-band was exhibited by the PP-CP, along with excellent joule heating, hydrophobicity, and breathability. The outstanding multifunctional integration features of PP-CP meet the needs of next-generation wearable electronic devices, while also paving a new path for the sustainable utilization of PP and carbon fiber resources.
