Zinc oxide with various surface characteristics and its role on mechanical properties, cure-characteristics, and morphological analysis of natural rubber/carbon black composites

Sustainable use of fly ash waste in tire tread rubber: Characterization of physical properties and environmental impact assessment

This study explores the use of fly ash (FA), a waste material, to partially replace zinc oxide (ZnO) as an activator in tire tread processing. Reducing ZnO addresses its environmental risks, particularly the impact of ZnO leakage into aquatic ecosystems throughout the tire's life cycle. The FA was altered by including rubber compound with and without ZnO, using ZnO-to-FA ratios of 3:0 (control), 2:1, 1:2, 0:3, or 0:5 parts per hundred of rubber (phr). The results show that crosslinking of the rubber compound occurred with FA, even in the absence of ZnO. Notably, sample recipes with ZnO-to-FA ratios of 2:1 and 1:2 phr had similar Δ torque values to the control (3:0), allowing for ZnO reductions of 33.7% and 67.0%, respectively. This effectiveness is likely due to metal oxides in FA, such as CaO, MgO, Al2O3, and Fe2O3, which support the vulcanization process. Additionally, tensile strength and modulus remained unchanged. Elemental analysis further indicated that a ZnO-to-FA ratio of 1:2 reduced zinc release by 63.0% compared to the control recipe. A gate-to-gate life cycle assessment revealed that replacing ZnO with FA in vulcanized rubber formulations reduces environmental impacts, with the lowest effects observed at the 0:3 ZnO:FA ratio, though higher FA content may increase impacts. Using FA as a partial replacement for ZnO in tire tread processing shows promise for reducing environmental impact in tire manufacturing by lowering zinc release, decreasing ecotoxicity, and promoting waste reduction through the recycling of fly ash.

Advancement of an Environmentally Friendly and Innovative Sustainable Rubber Wrap Film with Superior Sealing Properties

Common kitchen wraps like plastic and aluminum foil create significant environmental burdens. Plastic wrap, typically made from non-renewable fossil fuels, often ends up in landfills for centuries, breaking down into harmful microplastics. Aluminum foil, while effective, requires a large amount of energy to produce, and recycling it at home can be impractical due to food residue. A promising new alternative, low-nitrosamine rubber wrap film, aims to reduce waste by offering a reusable option compared to traditional single-use plastic wrap. The film is environmentally friendly, durable, and effective in sealing containers and keeping food fresh or crispy. The raw materials used to make the product were studied, namely fresh and concentrated natural rubber latex. No nitrosamines were found in either the fresh or concentrated latex, which is important as nitrosamines are known to be carcinogenic. The absence of nitrosamines in the raw materials suggests that the universal rubber wrap film is safe for use. In this study, the rubber formulation and properties of rubber used to make rubber wrap film were studied. The content of additives affecting the rubber properties was varied to find the optimum rubber formulation for making rubber wrap films. The rubber formulation with the least amount of chemicals that met the following criteria was selected: tensile strength of at least 15 MPa, elongation at break of at least 600%, and nitrosamine content below 6 ppm. It was found experimentally that the optimum rubber formulation for making a translucent rubber film had 0.7 phr zinc oxide and 1.0 phr sulfur. Performance tests revealed the rubber wrap film's superior sealing capabilities. Its elasticity allows for a tighter fit on containers, effectively conforming to various shapes and creating an optimal seal compared to plastic wrap and aluminum foil. The results of this study provide valuable information for developing a universal rubber wrap film that is safe with low nitrosamines.

Recent trends in industrial and academic developments of green tyre technology

Growing natural calamities as a consequence of global warming are one of the most pondering subjects today. The exponential growth of environmental pollution due to unscientific human exploitation of natural resources is considered the prime reason for the harsh responses of nature. Researchers from various fields of industry and academia are working hard to develop and implement products/technologies that are environmentally friendly or less harmful to the ecosystem. Material researchers, specifically those working in the automobile sector are also not behind in search of green products from eco-friendly raw materials and production methods. The automobile industry is collectively responsible for around 40% of global pollution in terms of greenhouse gas emissions. Out of which around 20-30% is originating from tyre production and its end-use. In this view, tyre production from eco-friendly raw materials and technologies that have minimum hazardousness to the environment is a hot research topic today. A few products in the market with "green" tags and many are in the pipeline for the recent future. This review summarises a detailed discussion of the emerging green technologies for tyre production and depicted comprehensive data from the available literature. The paper has been drafted from a well-balanced academic and industrial point of view since the researchers from both sectors are working in harmony for a better future for green tyre technology.