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Adhesive RA-72 is composed of 72% hexamethoxyl melamine and inert carrier. In conjunction with methylene receptor, it can effectively promote the adhesion between rubber and steel reinforcing material. RA-72 is a methylene donor.

Adhesive RA-72 leads to adhesion via reaction with methylene receptor, such as rubber adhesive RE, rubber adhesive GLR 20 etc. This reaction starts quickly at vulcanization temperature. If the reaction occurs before vulcanization, the adhesion of matching system will significantly decrease, or even disappear. Generally, rubber filler and methylene receptor are added and mixed at first with a high temperature, then adhesive RA-72 , sulfur and accelerator are added simultaneously at final mixing stage. 2-5 phr of RA-72 is suggested to be used with 2-5 phr of adhesive GLR-20.

RA-72 is packed in a paper bag lined with plastic bag. The net weight per bag is 25kg. It should be systematically stockpiled in a dry, clean and cool warehouse to avoid to be moistured, heated or deteriorated. The valid storage is one year.