Impacto ambiental do uso de óxido de zinco em formulações de borracha: estudo crítico e possíveis soluções

Abstract

Elastomers are a class of polymeric materials characterized by their high elasticity and ability to resist deformation and return to their initial state. Rubbers play an important role in the automobile, aeronautics, civil construction, medical, and consumer goods industries, with pneumatic products, inner tubes, sealing rings, soles, and coatings being some of the main applications. The properties of elastomers depend heavily on the vulcanization process, responsible for creating a network of cross-links by adding sulfur. Among the various additives used to ensure efficient vulcanization and a good set of properties, the use of zinc oxide as a process activator stands out. Although used in small quantities, the large volume of elastomeric products, mainly tires, means that global production of zinc oxide reaches 50 million tons. Although it plays a fundamental role in the production of elastomers, zinc oxide is associated with environmental problems, especially in aquatic environments. Because of this, alternatives are being sought to reduce or eliminate its use. In this work, a literature review was carried out to compare possible solutions to eliminate or reduce the use of zinc oxide. The total reduction of zinc oxide is unlikely, so solutions that use additional metal oxides as co-activators, silica nanoparticles or carbon are promising options to highly reduce the zinc oxide content in rubber formulations.