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A silicon oxide (SiO2) nanoparticles‐decorated short carbon fiber (SCF) hybrid (SCF‐SiO2) was designed to improve the weak interfacial bonding between fibers and matrix. Nano‐SiO2 was grafted onto carbon fibers by introducing amino group and epoxy group on the surface of carbon fibers and SiO2, respectively. The chemical composition of SCF‐SiO2 was analyzed by Fourier transform infrared spectrometer and energy‐dispersive spectrometry, the microstructure of SCF‐SiO2 were investigated by scanning electron microscope, and then the hybrid filler was introduced into Poly(ether ether ketone) (PEEK). Due to the strong interfacial interaction between filler and matrix, the mechanical and tribological properties of SCF‐SiO2/PEEK composites were significantly better than SCF/PEEK composites. In order to further improve the tribological properties of the composites, micrometer‐sized cenosphere (CS) particles were introduced into the aforementioned system to prepare multicomponent composites. The test results of friction and wear indicate that the CS/SCF‐SiO2/PEEK composites have the optimal tribological properties. Compared with pure PEEK, the friction coefficient of CS/SCF‐SiO2/PEEK composites under 200 N load decreases by 56.4% and the specific wear rate decreases by 87.4%. Meanwhile, the thermal decomposition temperature of CS/SCF‐SiO2/PEEK composites is increased by 40 °C compared to pure PEEK. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48749. [ABSTRACT FROM AUTHOR]

Biodegradable polymeric nanoparticles have received growing interest as one of the most promising agents for drug delivery. In the present work, functional and core-crosslinked poly(ethylene glycol) with poly(ϵ-caprolactone) (PEG5k-PCL10k) block copolymer and lecithin as biodegradable polymer doped with polyaniline was used to assemble nanoparticles which were prepared for targeted delivery and controlled release of cisplatin. The morphology of the polyaniline nanoparticles was determined by dynamic light scattering and the prepared nanoparticles showed a size of 83(±1) nm and a uniform spherical shape. For targeting to HER2 receptors, Herceptin was applied to guide the nanoparticles to breast cancer cells. Studies on cellular uptake and drug release of the nanocarriers showed that the prepared nanoparticles were efficiently taken up by breast cancer cells and the drug was released efficiently under acidic conditions when exposed to a near-infrared laser (808 nm, 1.54 W) for 5 min. Our research highlights the great potential of near-infrared light and pH dual-responsive release by core-crosslinked nanoparticles in nanobiomedicine. [ABSTRACT FROM AUTHOR]

This investigation focuses on the effects of cenosphere fillers on tribological properties of carbon fiber reinforced PEEK composites. Dry sliding wear behavior of 15 wt % short carbon fiber (SCF) reinforced PEEK composites filled with 5, 10, 15, and 20 wt % cenosphere was reported in this study, pure PEEK and 15 wt % SCF reinforced PEEK composites were also prepared for comparative analysis. Friction and wear experiments were conducted on a ring‐on‐block apparatus under different loads (100–400 N). The experimental results showed that all the composites exhibited lower coefficient of friction and better wear resistance than the matrix resin under different load conditions. It is noted that 10 wt % of the cenosphere particles filled SCF reinforced PEEK composites show superior tribological properties when compared to the other composites in this study. The morphologies of the worn surface and the fracture surface were analyzed by scanning electron microscopy and the transfer film was observed by optical microscope to understand the dominant wear mechanisms. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47245. [ABSTRACT FROM AUTHOR]