Highly Efficient Methods for Sulfur Vulcanization Techniques, Results and Implications: Selection and Management of Rubber Curatives

In this book, two new methods are described and supported by extensive experimental results that measure the amounts of a sulfur-donor thiuram accelerator and a sulfenamide thiazole accelerator needed to provide monomolecular coverage of zinc oxide. These methods use zinc oxide with only one accelerator and no stearic acid to produce two single additives, that can efficiently cure rubber, despite using fewer chemicals. This is a departure from the past when efficiency in sulfur vulcanization was achieved by using a high volume of these chemicals. A few sulfur-donor accelerators that exist produce highly toxic nitrosamines during high-temperature mixing and curing. When safer accelerators are on hand to treat the zinc oxide, a suitable single additive will be available to replace the current sulfur cure systems in industrial rubber formulations. This will bring huge benefits to the manufacturers and users of these chemicals. It is preferable to use zinc oxide to determine the precise amount of the accelerator required for a satisfactory cure rather than relying on outdated methods that need to be modified. A software is also developed to help with the selection and management of zinc oxide and the accelerators for the sulfur vulcanization. Green rubber products are within reach.