John Dick Technical Editor [email protected] See All Staff Page Recent Stories Technical Notebook: Quantifying differences among commercially used zinc oxide grades Zinc oxide is used as the main activator along with stearic acid in the vast majority of rubber formulations today. However, some have considered zinc oxide as just another industrial chemical. This paper compares different grades of zinc oxide in critical rubber compounds. John Dick: Reflections on RPN and the rubber industry John Dick had just started his career when Rubber & Plastics News made its debut. The industry and the publication, he said, have changed for the better.