Ionogels is a kind of hybrid materials composed of ionic liquids (ILs) and solid polymer network matrix, has been extensively investigated in the most recent decade. Due to the excellent mechanical properties and ionic conductivity, their promising applications in flexible stress and strain sensors have been proposed and explosively developed. In this review, we briefly summarize research progresses on ionogel based flexible stress and strain sensors (IFSSs) from five aspects, including material synthesis, device fabrication, working principles, characteristics and performances, and potential applications. Some outlooks and perspectives are also proposed at the end of review. The review is expected to provide reference and new insights into the research of IFSS. Graphical abstract

In recent years, core–shell composite particles with organic polymer as the core and inorganic SiO₂ as the shell have attracted widespread attention and prompted robust scientific endeavors. The encapsulation of SiO₂ can endow the polymer core with a variety of important properties, and is of great significance for the synthesis of multi–functional materials, having favorable application prospects in coating, polishing, medical, optical, magnetic, lubrication and other fields. In this paper, the recent advances in the preparation of core–shell polymer@SiO₂ composite particles are reviewed. From the perspective of interface bonding mechanisms between the core and the shell, this paper mainly focused on the following five aspects: Pickering stabilization, acid–base interaction, charge interaction, bridging of coupling agent, hydrogen bonding, and other actions. Additionally, applications of core–shell polymer@SiO₂ particles are also discussed. It is expected that this article can provide scientific guidance for the preparation of polymer@SiO₂ core–shell particles, further enriching their species and broadening their applications.

Owing to good self-lubricating performance, tin bronze is widely used in industrial fields. As tin bronze parts manufactured by powder metallurgy, their tribological performances are influenced by raw powder. In this work, four types of self-lubricating copper alloy composites (CuSn10 (D), CuSn10, CuSn10Pb10 (D) and CuSn10Pb10) were prepared by sintering completely alloyed powder and diffusion alloyed copper tin powder. The morphology, element distribution and microstructure of raw powder and their sintered Cu alloy composites were observed. The tribological properties of Cu alloys were investigated by block-ring friction test under different working conditions and their worn surface and wear debris were analyzed. The results show that the diffusion alloyed powder has an irregular dendritic morphology and its sintered Cu alloy is more likely to produce twin structure which enhances the hardness and the bearing capacity of the material. Compared with completely alloyed powder sintered CuSn10 sample, the wear rate of CuSn10 (D) sintered from diffusion alloyed powder was reduced by 83.96%, 74.39%, and 67.63% under three typical working conditions. Under dry friction conditions, the wear rate of CuSn10 (D) is reduced by 63.64% than CuSn10, and CuSn10Pb10 (D) is 25% lower than CuSn10Pb10. The investigation on the wear tracks and wear debris of Cu alloy composites showed that the diffusion alloyed powder sintered samples are inclined to form a more consecutive and integral third-body layer on wear tracks and which contributes to the better wear resistance.