Metallic Stearates: A Review of their Function and Use as Release Agents for Rubber Compounds*

Abstract

Metallic stearates have a long history of use in the rubber industry as release agents. They have been primarily used tkeeping uncured rubber from sticking to itself. Metallic stearates have also been used as mould release agents for cured rubber. The applications of these products are numerous and many rubber companies have found unique ways to utilise their physical and chemical properties. In this paper we will discuss these products in detail, including the following: chemistry, physical properties, compatibility with elastomers, environmental concerns, and their function as release agents for rubber.

Metallic stearates can be supplied in various forms such as their dry neat state, dispersed in water and alcohol, and formulated with surfactants that provide a wettable grade. These various forms will be discussed as to their function and use in a rubber manufacturing facility.