الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
It has been observed that strong adhesion between natural rubber and three types of steel cords, namely, brass-coated, copper-coated and uncoated steel can be obtained by using cobalt-organic salts such as industrially produced cobalt stearate and naphthenate, and laboratory prepared cobalt palmitate and myristate. Also some other compounds were used as adhesion promoters such as hexamethylene tetramine/resorcinol, resorcinol-formaldehyde resin, sulphur, carbon black and fumed silica. Synergistic effect between cobalt stearate and cobalt palmitate was demonstrated.
Adhesion of vulcanized rubber to steel cords was carried out as given in ASTM designation: D 2229-73. The preparation of rubber compound and vulcanization were carried out as described in ASTM designation: D15-60 T. Some rheological characteristics were determined by using oscillating cure meter (rheometer) and shearing disk visometer as given in ASTM designations: D2084-71T and D1646-72. The physico- mechanical tests were performed in accordance with ASTM designations: D412-D2240-68 and D1054-66. The most likely mechanism by which natural rubber adheres to copper coated and brass-coated steel is the growth of CuS dendrites with a high specific surface area into the compound before the liquid