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Flexible multifunctional polymer-based electromagnetic interference (EMI) shielding composite films have important applications in the fields of 5G communication technology, wearable electronic devices, and artificial intelligence. Based on the design of a porous/multilayered structure and using polyimide (PI) as the matrix and polymethyl methacrylate (PMMA) microspheres as the template, flexible (Fe3 O4 /PI)-Ti3 C2 Tx -(Fe3 O4 /PI) composite films with controllable pore sizes and distribution of Ti3 C2 Tx hollow microspheres are successfully prepared by sacrificial template method. Owing to the porous/multilayered structure, when the pore size of the Ti3 C2 Tx hollow microspheres is 10 µm and the mass ratio of PMMA/Ti3 C2 Tx is 2:1, the (Fe3 O4 /PI)-Ti3 C2 Tx -(Fe3 O4 /PI) composite film has the most excellent EMI shielding performance, with EMI shielding effectiveness (EMI SE) of 85 dB. It is further verified by finite element simulation that the composite film has an excellent shielding effect on electromagnetic waves. In addition, the composite film has good thermal conductivity (thermal conductivity coefficient of 3.49 W (m·K)-1 ) and mechanical properties (tensile strength of 65.3 MPa). This flexible (Fe3 O4 /PI)-Ti3 C2 Tx -(Fe3 O4 /PI) composite film with excellent EMI shielding performance, thermal conductivity, and mechanical properties has demonstrated great potential for applications in EMI shielding protection for high-power, portable, and wearable flexible electronic devices. The authors are grateful for the support from the National Natural Science Foundation of China (U21A2093 and 51973173), Technological Base Scientific Research Projects (Highly Thermally Conductive Nonmetal Materials), Fundamental Research Funds for the Central Universities, and Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University (CX2021107 and CX2022073). This work was also financially supported by the Polymer Electromagnetic Functional Materials Innovation Team of Shaanxi Sanqin Scholars.

Composites of styrene butadiene rubber (SBR), hydrogenated acrylonitrile–butadiene rubber (HNBR) and silica were prepared. Sulfur (S), dicumyl peroxide (DCP) and a combination of S and DCP (M) were used as curing agents, respectively. The morphology of the composites with different blend ratio was examined to correlate with observations on mechanical properties by scanning electron microscopy. The effects of blend ratio and curing systems on the curing characteristics and mechanical properties, such as stress–strain behavior, tensile strength, elongation at break and hardness of SBR/HNBR/Silica composites, were studied. Composites prepared by M curing systems showed comparatively better mechanical properties, wet traction and rolling resistance than S and D curing systems. The tensile strength, tear strength, and elongation at break were improved by adding HNBR for M curing systems. The wet traction of the vulcanizates containing HNBR was better than that of the vulcanizates without HNBR. A relatively uniform dispersion of silica was observed for SBR/HNBR/silica compositions compared with SBR/silica composites.

Graft polymerization of vinyltriethoxysilane (VTES) onto styrene-butadiene rubber (SBR) was carried out in latex using benzoic peroxide (BPO) as an initiator. The concentration of VTES effecting on vulcanization characteristics, mechanical properties and thermal properties of VTES-grafted SBR (SBR-g-VTES) were investigated. The grafting of VTES onto SBR and its pre-crosslinking were confirmed by attenuated total teflectance-Fourier transform infrared reflectance and proton nuclear magnetic resonance. The mechanism of graft polymerization was studied. The results revealed that the minimum torque, optimum cure time, tensile strength, thermal decomposition temperature, and glass transition temperature (Tg) all increased with the increasing concentration of VTES. But the grafting efficiency of VTES, rate of vulcanization, and elongation at break of the SBR-g-VTES decreased. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The surface-modified dental barium glass with silane coupling reagent KH-570 was studied. The prepared samples before and after modification were characterized by static precipitation, angle of contact, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared ray, and thermo-gravimetric analysis. Research showed that the KH-570 was bound on the surface of barium glass, a firm chemical bonding of KH-570 to barium glass and an organic layer was formed, and the maximum mass fraction of KH-570 coated on the barium glass surface measured was about 2.86%. The surface performance of modified barium glass changed from hydrophilic to hydrophobic. Mechanical tests revealed that the mechanical properties of composite resin filled by KH-570 modified barium glass improved simultaneously.