An antibacterial natural rubber (NR) latex film was successfully prepared in this study. This was done by coating silver (Ag) nanoparticles onto the surface of the NR latex film. The Ag nanoparticles were synthesized using green tea (GT) extract as a bio-reducing agent. The corresponding Ag nanoparticles were then deposited onto the NR latex film. Before synthesis, the phenolic compounds were identified using high-performance liquid chromatography (HPLC). The Ag nanoparticles were found to be smaller than 25 nm in size. Subsequently, an experimental evaluation was conducted to determine the influence of deposition time, namely 1 to 20 min, on the film’s overall performance. Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (SEM-EDX) confirmed that the Ag content was higher over the deposition time. The surface roughness of the samples was also screened by atomic force microscopy (AFM), where the films became rougher over the deposition time, confirming that Ag nanoparticles dispersed over the surface. As for the antibacterial activities, both qualitative and quantitative tests showed significant outputs. The clear zones of S. aureus and E. coli increased over the deposition time, and a shorter contact time was used to kill the bacteria. This study offers a scientific foundation that supports the development of future rubber products utilizing these findings.

Waste rubber disposal causes considerable negative environmental impacts due to its increase worldwide, mainly in the automotive industry. Therefore, the search for technological solutions for rubber waste is a priority, and the first step in this material degradation is devulcanization due to its difficult degradation. This study evaluated rubber devulcanization using a closed vessel microwave digestion system with nitric acid (HNO₃) and hydrogen peroxide (H₂O₂) through chemical characterization, aiming at verifying the synergistic effect between these oxidizing agents. Microwave irradiation was applied as a heating method to facilitate the chemical reactions, focusing on the synergism between HNO₃ and H₂O₂. Results showed that 5 M H₂O₂ in combination with 1% HNO₃, presented better results. A greater decrease in cross-link density was demonstrated as the concentration of H₂O₂ increased (3.96·10^–5±1.99·10^–6 mol/cm³), likewise, higher sulfates released (926.8±53.4 mg/L), increased mass loss (12.184±1.06%), rubber surface fragmentation, and important variations in the C–S, C=O bands, showing better results when devulcanization is carried out in synergism between HNO₃ and H₂O₂.

Inspired by the micro structure of loofah sponge in nature, this article successfully employs a biomimetic approach to develop a novel series of natural Eucommia rubber foamed materials with excellent shape memory properties. This article explores the characteristic features of natural Eucommia ulmoides rubber foamed materials, including the foaming process, mechanical properties, shape memory performance, and adsorption properties. This paper introduces the innovative use of natural Eucommia ulmoides rubber’s shape memory properties to create a temperature-responsive foam adsorbent material. The foamed material’s unique ability to modify its pore structure through simple compression and heating processes offers tailored adsorption speed and capacity for varied practical applications. The adjustable adsorption properties of this foamed material present novel opportunities for its utilization in adsorption applications.

This study investigated the properties of the natural rubber (NR) foam filled with azodicarbonamide (ADC) blowing agents by combination to various ratios of epoxidized NR (ENR) for flexible foam applications. Compound operation was prepared with an open two-roll mill and the production was fabricated by compression molding. The study elucidated properties related to crosslinking behaviors, mechanical and dynamic properties, elasticity, abrasion, weathering resistance, and sound absorption efficiency. The ENR and ADC concentrations affected the tensile testing and also the durability properties of the NR/ENR. The NR and ENR foam of 60/40 filled with 10 phr of ADC demonstrated good properties across various parameters, showing acceptable tensile properties, abrasion resistance, and QVA light resistance. Additionally, the presence of a closed-cell structure in the blends reduced crack propagation in the NR matrix during aging, improving weathering resistance. The absorption coefficient increased with higher ADC content, being optimal at 15 phr, due to the lower density and higher porosity of the opened-cell material, which enhances its ability to interact more effectively with incoming energy at 1600 and 6400 Hz. The findings encourage the use of ENR for blending in NR for improved ENR and ADC concentrations since dipole-dipole interaction from ENR-ADC caused ADC dispersability, providing complexed foam structures for force expansion and aslo sound wave absorption.

Natural rubber (NR) composites filled with silica and crosslinked with phenolic resin were prepared in this study. The influence of a small sepiolite addition (1–5 part(s) per hundred parts of rubber, phr) on the properties of NR composites was studied. It was found that sepiolite reduced silica aggregate size, allowing improved dispersion in the NR matrix. Sepiolite facilitates silica dispersion by locating at the silica surfaces and acting as a barrier that prevents agglomeration of silica filler. The swelling resistance, crosslink density, tensile strength, and strain-induced crystallization were all strengthened by incorporating sepiolite because of the improved silica dispersion. The greatest tensile strength was achieved at a 2 phr sepiolite addition level. The improvement was about 18% over the reference composite due to the greatest filler-rubber interactions and the finest filler dispersion. The results clearly indicate that sepiolite clay can be applied as a dispersing agent in silica-containing rubber composites.