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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.

Modifying natural rubber latex (NRL) and blending it with NRL can improve NRL performance and expand application elds. The performance of co-blended latex will change due to changes in non-rubber components during storage. Therefore, it is important to study the change of properties during the storage of co-blended latexes. In this paper, 30% methyl methacrylate grafted natural rubber (MG30) was synthesized by cumene hydroperoxide/ tetraethylenepentamine (CHPO/TEPA) initiating system, MG30 and NRL were mixed in different proportions to study the morphology and physical and mechanical properties, and the colloidal properties and emulsion properties of co-blended latexes were studied during storage. The results showed that the mechanical stability of NRL and co-blended latexes were high and the viscosity gradually increased during storage. The study of the vulcanization characteristics of the coblended latexes lms and the physical and mechanical properties of the vulcanized latex lms showed that the vulcanization time of the co-blended lms increased and the torque value increased in comparison to NRL. With the increase of MG30 content, the tensile strength and tear strength of the coblended latexes vulcanized lms showed a trend of increasing and then decreasing, and the co-blended lm with 10% MG30 showed the best mechanical properties.

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