Herein, the electromagnetic interference (EMI) shielding and electrothermal properties of MXene‐coated cellulose hybrid papers (MCPs) and fabrics (MCFs) with high flexibility and low density, which are manufactured by a dip‐dry coating approach, are reported. For this purpose, MCPs and MCFs are fabricated by dipping cellulose papers and fabrics repeatedly into an aqueous dispersion of MXene. The electron microscopic and X‐ray diffraction data reveal that MXene sheets are coated uniformly on the surfaces of cellulose fibrils and fibers and that their contents increase with the dip‐dry coating cycle. For MCP10 (5.68 wt% MXene) and MCF10 (11.77 wt% MXene), which are manufactured by ten‐time dip‐dry coating cycles, high electrical conductivity of 1.91 and 0.08 S cm−1 are attained, respectively. In addition, MCP10 and MCF10 possess excellent absolute EMI shielding effectiveness (SSEt) of 2198 and 1100 dB cm2 g−1 at 8 GHz, respectively, which is due to the multiple internal reflection and absorption of incident EM waves by conductive and interconnected MXene‐coated cellulose fibrils and fibers. It is also found that MCP1 (0.9 wt% MXene) and MCF1 (1.9 wt% MXene) at one‐time dip‐dry coating cycle show outstanding electrothermal performance in aspects of high saturated temperatures and energy conversion efficiency at low applied voltages.

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To attain thermoplastic polymer composites with enhanced thermal and mechanical properties as well as long‐term durability, in this study, polyurethane‐coated carbon fiber (CF) and electron beam (EB) irradiation are adopted as an effective reinforcing filler and efficient crosslinking process, respectively. For this purpose, polyamide 6 (PA)‐based composites with different CF contents of 1–10 wt% were fabricated through melt‐compounding and compression molding, and then irradiated with various EB doses of 50–200 kGy. The SEM and FT‐IR data reveal that CFs are well dispersed in the PA matrix with excellent interfacial adhesion via specific intermolecular interactions, which are even enhanced for the composites with crosslinked PA matrices after the EB irradiation. As the result, the thermal stability (initial decomposition temperature and residue at 800°C) and dynamic mechanical properties of PA/CF composites increased noticeably with increasing the CF content and EB irradiation dose. The initial storage modulus of 1.90 GPa for neat PA at 30°C was improved significantly to 2.94 GPa by 10 wt% CF addition and to 4.67 GPa by 200 kGy EB irradiation. In particular, the long‐term mechanical properties of PA/CF composites, which were evaluated using a stepped isothermal method based on the time–temperature superposition principle, were found to be highly enhanced by the synergistic effect of CF filler reinforcement, EB‐induced PA matrix crosslinking, and improved interfacial adhesion.

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We report the effects of reactive compatibilization on the morphology, microstructure, and physical properties of thermotropic liquid crystalline polyester/poly(1,4‐cyclohexylenedimethylene terephthalate) (TLCP/PCT, 75/25 by wt%) blends, which are fabricated via melt‐compounding in the presence of different catalyst types and contents. Among three different catalysts, titanium butoxide (TBT) is found to be most effective in the reactive compatibilization of TLCP/PCT blends, which is confirmed by SEM images. FT‐IR spectroscopic analysis reveals the formation of copolyesters by catalyst‐induced transesterification between TLCP and PCT components during melt‐compounding with 0.5 and 1.0 phr TBT loadings. Nonetheless, X‐ray diffraction analysis confirms that the crystal structures of TLCP/PCT blends are not affected by reactive compatibilization. The melting and crystallization transition temperatures of the PCT component in the compatibilized blends decrease owing to the shortening of crystallizable PCT segments by the transesterification. TGA data show that the residue at 800°C increases for the blends melt‐compounded with higher TBT catalyst loadings. The shear moduli and complex viscosity of compatibilized TLCP/LCP blends at a melt state are found to be even higher than neat TLCP and PCT. Although the elastic storage moduli of compatibilized TLCP/PCT blends are slightly lower than neat TLCP, they are far higher than neat PCT.