Kaolinite supported cerium oxide (CeOx/Kaol) was successfully prepared via a deposition method and used to improve the mechanical and aging properties of styrene–butadiene rubber (SBR) composite. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results showed that cerium oxide has a successfully loading and fine distribution on the edge and surface of kaolinite. Fourier transform infrared (FT-IR) spectroscopy indicated that cerium oxide may interact with the surface hydroxyls of kaolinite. The CeOx/Kaol material had a uniform dispersion in the resulting SBR composite. The loading of cerium oxide on Kaol increases the scorch time (t₁₀) and curing time (t₉₀) of the filled SBR composites relative to the pure SBR. The mechanical parameters of the filled SBR composites were increased significantly. The tensible strength and tear strength at 40 phr content with 4% CeOx loading reached 12.85 Mpa and 51.16 kN/m, which were increases of 35.9% and 38.3%, respectively, relative to that of the SBR filled with raw Kaol. The anti-ageing characteristic of the resulting composite showed an obvious improvement with the loading of CeOx. Meanwhile, the reinforcement and anti-ageing mechanisms of the CeOx/Kaol were proposed. These results were attributed to the complexation between Ce elements on the surface of Kaol and rubber chains through a double bond. This could improve the incorporation between rubber molecules and filler particles, and restrict rubber chain motion via trapping rubber chains.

The particle size of catalyst active components is a key factor for catalytic activity. In this work, functionalized halloysite (Hal) provides a synthetic strategy for the preparation of catalysts loaded with small Pd particles. In this study, halloysite nanotubes were employed as catalyst supports, and the ac-Hal support was synthesized via mild treatment of halloysite nanotubes with acetic acid (ac). The ac-Hal-Pd catalyst was prepared by the coprecipitation method and exhibited excellent catalytic activity for toluene oxidation, with a temperature for 90% toluene conversion (T₉₀) of 179 °C. Transmission electron microscopy (TEM), CO pulse chemisorption, and CO adsorption in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analyses revealed that the Pd particles on the surface of the ac-Hal-Pd catalyst had a smaller particle size and more uniformly dispersed Pd particles. X-ray photoelectron spectroscopy (XPS) and O₂-temperature-programmed desorption (O₂-TPD) analyses indicate that the reduction in the particle size of Pd particles increases the proportion of Pd⁰ on the catalyst surface and the concentration of adsorbed oxygen, which is also a key factor for the enhancement of catalytic activity. In situ DRIFTS spectra of NH₃ adsorption reveal that ac-Hal-Pd possesses a higher abundance of Lewis acid sites, which is favorable for the catalytic reaction. In situ DRIFTS results suggest that toluene oxidation over ac-Hal-Pd proceeds through the formation of benzyl alcohol/alkoxy species, benzaldehyde, benzoate/benzoic acid species, and maleic anhydride intermediates, which are finally oxidized to CO₂ and H₂O.