Enhancing the Adhesion Retention by Controlling the Structure of the Adhesion Interphase between Rubber Compound and Metal. Part II. Effect of Zinc Borate

摘要

The adhesion between zinc borate-containing rubber compounds and brass-plated steel cords was studied to understand the role of zinc borate as an adhesion promoter. No improvement in adhesion after cure was shown with loading of zinc borate in the range 0.5-2 phr, while enhancement of adhesion retention after humidity aging was observed with loading of zinc borate in the range 0.5-2 phr. The adhesion interphase between the brass-plated steel cord and the rubber compound subjected to humidity aging treatment showed, using AES, a stabilized depth profile by a moderate loading of zinc borate, resulting in enhancement of adhesion retention. For the high loading of zinc borate, copper sulfide layer and zinc oxide layer grew excessively in the adhesion interphase under humidity aging.