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Self-assembled buckypapers have been successfully prepared using sodium carboxyl methyl cellulose (CMC) as a binder. The lowest resistivity that was reached was 0.43 ± 0.03 Ω·m, when the buckypapers were prepared by the same mass of CMC and carboxy-modified carbon nanotubes (CNTs). A heat-resistant electroconductive nanocomposite with epoxy resin as the matrix and CMC/buckypapers as the reinforcement was fabricated by a resin impregnation molding technique. The effects of CMC/buckypaper layers on the conductivity, thermal stability, and mechanical and dynamic mechanical performance of the epoxy resin polymer nanocomposites were investigated. It was found that CMC/buckypapers hold great promise for improving the properties of nanocomposites, and the buckypapers’ performance can be enhanced by using modified CNTs to prepare them. The obtained nanocomposites showed an approximate 71.23% bending strength improvement (125.04 ± 5.62 MPa) and a 30.71% bending modulus improvement (5.83 ± 0.68 GPa), with an increased number of CMC/buckypaper layers. An enhanced degradation temperature and residual mass were also achieved for the nanocomposites when compared with a pure polymer. The nanocomposites with four CMC/buckypaper layers possessed the highest storage modulus (1934 MPa), which was approximately 60% higher than that of a neat polymer (1185 MPa). Therefore, CMC/buckypapers could be effectively used to manufacture heat-resistant electroconductive polymer nanocomposites with improved properties.

The heterogenization of homogeneous catalysts is one promising approach to achieve recyclability and reusability of catalyst, while it inevitably tied to the poorer accessibility of reactants and less effectiveness of catalytic sites. Herein, we present a hollow porous organic frameworks (HPOFs) with unique large hollow cavity, hierarchical porous shell and well dispersed catalytic active sites. The shell thickness of HPOFs is controllable via tune the amount of building blocks. Compared with their solid counterpart, the hollow interior of HPOFs accelerated the mass transfer of reactants into catalytic sites and products out of catalyst skeleton. Meanwhile, the hierarchical porous thin shell exposed more active catalytic species to interact with substrate molecules. These advantages enable HPOFs to best maintain the performance of homogeneous counterpart after heterogenization. The relationship of catalytic activity and hollow structure was investigated by the cycloaddition reaction of CO 2 with 2-(chloromethyl)oxirane in the absence of solvents, co-catalysts and additives. The catalytic activity increased gradually with the decrease of shell thickness. This work provides a new insight for the development of heterogenization of homogeneous catalysts based on hollow porous organic frameworks.

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Carbon fiber‐reinforced polymer composites (CFRPs) are widely used in many fields because of their excellent mechanical properties; however, they are very sensitive to low velocity impact. A new‐type biomimetic structure, which has a “bricks‐and‐mortar” arrangement of nacre from mollusk shells, was designed and manufactured for enhancing the impact resistance of the CFRPs. The impact response and absorption of impact energy of this structure were also investigated. Impact damage forms of the biomimetic structure were analyzed based on the surface and internal morphologies. The results indicate that biomimetic structure can decrease the impact damage of the CFRPs. Two damage behaviors of the biomimetic structure were observed under relatively higher impact energy. The discontinuous structure reduces the damage using a smaller load for the first damage and a larger deformation for the second damage, which improves the impact resistance of the CFRPs. The discontinuous structure restrains longitudinal crack propagation to a certain extent, effectively reducing the damaged area of the CFRPs. Thus, the proposed structure can increase the strength retention rate of the material by about 5%. In addition, the compression after impact damage modes of CFRPs with three types of structure are summarized and classified originally.