Abstract
The authors investigated the adhesion of rubber compounds containing nickel blanched alkyl carboxylate to surface treated magnesium alloys during curing. Ni i-octylate and Ni i-stearate were used as nickel branched alkyl carboxylate. Rubbers used in the study did not adhere at all to magnesium alloys, such as AZ91, AZ31, AZ 21, and M1 washed with acetone; not even in the presence of Ni i-octylate. Among numerous treating solutions, only sodium hydroxide aqueous solution was effective for adhesion of rubber to magnesium alloys. Adhesion of rubber to magnesium alloy AZ31 treated in 0.5M- sodium hydroxide aqueous solution for 10 min at 80 °C yielded high peel strength and a 100% rubber coverage. Peel strength and a 100% rubber coverage varied with the concentration of additives, such as curing accelerators, sulfur, zinc oxide and Ni-type adhesive accelerators. Ni branched alkyl carboxylates such as Ni i-octylate and Ni i-stearate were effective for accelerating the adhesion of rubber to magnesium alloys treated in sodium hydroxide aqueous solutions during curing. The authors postulate that Ni branched alkyl carboxylate acts to yield interface bonds between magnesium alloys and rubber or Ni-S-rubber linkage.