In the Rubber Industry, particularly in regard to the tires application, different compounds are utilized as anti-degradation agents, including the anti-oxidation and anti-ozonation agents. The latter perform a protection function against the harmful effects of prolonged exposure to atmospheric ozone and solar light. Ozone (O₃) is the oxygen form with the highest free energy, which is generated from the ultraviolet ray effect or from an electric discharge on molecular oxygen (O₂).

It is believed that rubber might break as the result of an oxidation process, taking place on the double bonds present inside the rubber structure. This situation might cause the rubber drying and incipient cracking, thus leading to the final rubber breaking under stress.

The anti-oxidation agents, generally diphenyl amines, phenols and bisphenols, slow down considerably the rubber oxidation process, reacting with the hydroperoxides and producing in turn some compounds that do not react with the rubber structure.

In turn, the anti-ozonation agents act generating a physical protection barrier, avoiding the ozone reaction with the rubber structure. These materials are made up from special mixtures of single chain hydrocarbons- from paraffin waxes- and from ramified chain hydrocarbons- from microcrystalline waxes-, with a very stringent carbon distribution, normally centered in high molecular weights (C28-C33).

Due to the increased needs for protection in the tires industry, Multiceras has worked extensively in the development of new anti-ozonation waxes, which provide a better protection to the tires manufactured for the automotive industry.

Working together with prestigious tires manufacturers, three special wax products have been developed for this application: Nozono Wax 29-32, Nozono Wax 31-33 and Nozono Wax A. One of the most important characteristics of this type of products is the specific carbon distribution, centered in the hydrocarbon compounds that provide the greatest anti-ozonation protection. This characteristic is achieved by means of a stringent process control, backed up by accurate gas chromatography analysis.

These waxes are fully compatible with any rubber specification, and they can be blended with the polymers and other chemical ingredients used in the tire manufacturing process. During the initial tire rolling, the polymer bends allowing the protective wax migration on the tire surface, forming a physical protection barrier between the tire polymer and ozone. This phenomenon is known with the name of “Eflorescence”.

Application Table for the Rubber Industry

Notes:
Melting point is determined by the ASTM D127 method. Penetration (dmm) by means of the ASTM D1321 method. Color by the ASTM D1500 method.