2001 Volume 74 Issue 12 Pages 483-489
Thin organic films formed on stainless steel SUS 304 BA substrates by polymer plating of different 6-substituted-1, 3, 5-triazine-2, 4-dithiol monosodium (RTDN) monomers were characterized using reflection absorption Fourier transform infrared spectroscopy (RAS FT-IR), specular reflection FT-IR, transmission FT-IR spectroscopy, Raman spectroscopy, and electron spectroscopy for chemical analysis (ESCA). The insoluble fractions of thin organic films in tetrahydrofuran (THF) were measured representing the cohesive strength or crosslinking extent of the films. RTDN monomers were electrochemically polymerized to triazine thiol polymers containing S-S bonds on the metal substrates through polymer plating treatment. The average orientation of the triazine rings and substituted groups in films was anisotropic and perpendicular to the substrates. The thin organic films were covalently bound to substrates through the S-Fe, or S-Cr bonds. The effect of film crosslinking extent and reactivity to rubber molecules or curing agents on the adhesion strength of adherend of polymer plated metal to peroxide cure system ethylene-propylene rubber (EPDM) was elucidated. In order to obtain high adhesion strength, it is necessary for the thin organic film to have three properties showed as follows: (1) to form chemical bonding at the film/metal interface, (2) to form chemical bonding at the film/rubber interface, (3) to have enough film cohesive strength. The thin organic film by the polymer plating of RTDN monomer just like 6-diallylamino -1, 3, 5-triazine-2, 4-dithiol monosodium (DAN) acts as a reinforcing layer at the interface between metal and rubber to improve the adhesion strength of the adherend.
