Urethane adhesive cord treatment for power transmission belt and belt
A belt with a tensile cord embedded in an elastomeric body, having an adhesive composition impregnating the cord and coating the fibers. The adhesive composition is the reaction product of a polyisocyanate and a polyol, or a polyurethane prepolymer derived therefrom, and a polyamine curative and optionally additional polyol, and with optionally added plasticizer. At least one of the polyisocyanate, the prepolymer, and the polyamine are blocked with a blocking agent. The belt body may be of cast polyurethane, vulcanized rubber, or thermoplastic elastomer. The cord may have an adhesive overcoat.
1. A belt comprising: an elastomeric body, and a carbon fiber tensile cord embedded in the elastomeric body;
with the tensile cord impregnated with an adhesive composition comprising the reaction product of:
a polyisocyanate and a first polyol or a polyurethane prepolymer comprising said polyisocyanate and said first polyol; and
at least one curative selected from the group consisting of diamines, triamines, and tetramines;
wherein at least one of said polyurethane prepolymer, said polyisocyanate and said curative has its reactive groups blocked by a blocking agent;
wherein said at least one of said polyurethane prepolymer, said polyisocyanate, and said curative is blocked curative complex 4,4′-methylenebisdianiline-NaCl.