With the emerging of sustainability, the fabrication of effective and eco-friendly agents for rubber industry has attracted extensive attention. In this study, a novel and nontoxic titanium dioxide-based vulcanization accelerator (xanthate-modified nanotitanium dioxide (TDSX)) with excellent antibacterial performance, for the first time, was synthesized under the catalyst of ceric ammonium nitrate. Notably, the thermal stability of xanthate was greatly enhanced after being grafted on titanium dioxide (TiO2) nanoparticles, in which the activation energy was increased from 6.4 to 92.5 kJ/mol, enabling the obtained TDSX with multiple functions, mainly consisting of fabulous vulcanization-promoting effects, reinforcing effects, antibacterial properties, and anti-ultraviolet aging effects for natural rubber (NR). Simultaneously, the TDSX can be effectively and uniformly dispersed in the rubber matrix along with the developed interface interaction between TDSX particles and rubber matrix. Compared to the traditional accelerators 2-mercaptobenzothiazole (M) system, the tensile strength and the tearing strength of NR/TDSX was improved by 26.3 and 40.4%, respectively. Potentially, our work for preparing green vulcanization accelerator can provide a new design strategy for multifunctional high performance elastomer materials.

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Natural rubber latex (NRL) is commonly employed to manufacture medical protective appliances. However, the characteristics of weakness and fragility of NRL membranes limit their further application. To achieve excellent strength and damage-resistance of the rubber membrane, this work reported a facile core–shell structure construction strategy via self-assembly with modified sodium lignosulfonate (MSLS) and NRL to create a tough membrane. The double network can be formed after introducing polyamide epichlorohydrin resin (PAE) into the NRL membrane. Specifically, the first robust MSLS-PAE network can break in advance to dissipate applied energy, thereby achieving high fracture energy and tensile strength of ~111.51 kJ m−2 and ~37 MPa, respectively, which overtakes numerous soft materials. This work facilitates more studies on latex/lignin-based products with high performance and good stability for the functional application of biopolymer.

To effectively screen pathogens or eliminate allergy symptoms caused by the protein in natural latex products, the strength of the natural latex film must be improved and the water‐soluble protein content in the latex products must be reduced. In this article, response surface methodology was used to optimize the reaction conditions for the preparation of hydroxyapatite (HA), and the reinforcement and adsorption of water‐soluble proteins on natural rubber latex (NRL) by HA modified by coupling agent KH550 were studied. Modified HA was homogenously dispersed in the NRL, and the tensile and tear strengths of the rubber film were increased by 37.45% and 40.86%, respectively. In addition, modified HA adsorbs the water‐soluble protein from the latex film. Compared with pure NR film, its protein content is reduced by 50.79%. This article has a reference value for the preparation of high‐performance natural latex film with low protein content.

Since the outbreak of COVID‐19, the demand for natural latex products with increased mechanical properties and aging resistance has surged. Based on the excellent adhesion and antioxidant properties of polydopamine (PDA), we employed a one‐pot method to modify the surface of silica substrates using PDA containing a polyphenol structure, to prepare a reinforced silica‐PDA composite latex material with antioxidant properties. As expected, the silica‐PDA composite achieved both uniform dispersion and good interfacial interactions with natural rubber latex (NRL). In addition, compared with common NRL/silica films, the mechanical properties of the NRL/silica‐PDA film were significantly improved; specifically, silica‐PDA can highly‐enhanced the mechanical property of NRL film from 24.94 to 32.18 MPa of tensile strength. Further, the antioxidant activity of the silica‐PDA film exceeded that of commercially available antioxidant D. Considering the notable performance boost of silica‐PDA composites on NRL films, we believe that the treatment of silica with natural polyphenols offers a convenient and facile new route for the preparation of environmentally friendly multifunctional silica additives.