Effect of magnesium methacrylate and zinc methacrylate on bond properties of thermal insulation material based on NBR/EPDM blends

To improve the bond property between thermal insulation composites and metal surface, magnesium methacrylate (MDMA) and zinc methacrylate (ZDMA) were added into NBR/EPDM blends, respectively. The results indicated that the dispersion of MDMA powder was very well and its content changes much smaller in the composites than that of ZDMA. As a result, with the dosage of MDMA increasing from 0 phr to 7 phr, the polarity of MDMA/composites was improved gradually due to the increasing of ionic crosslink density and the decreasing of contact angle. Therefore, the bond strength of the composites to metal increased continuously. And the failures of bonding samples were all in MDMA/composites. After adding ZDMA instead of MDMA into the rubber, however, ZDMA powder would agglomerate during being vulcanized. Therefore, the bond strength of the composites firstly increased slightly and then decreased sharply once ZDMA was over 2 phr, whereas the contact angle of ZDMA /composites is much lower than that of MDMA/vulcanizates. Moreover, all the bonding samples failpd at the interface of metal.