Carbon cord for reinforced rubber products and the products
A treated carbon fiber tensile cord for use in power transmission belts, hose, tires or other reinforced rubber products and the resulting product, which includes carbon fibers which are coated with a polymeric layer deposited and polymerized at atmospheric pressure in a plasma assisted chemical vapor deposition process. A suitable polymeric layer is compatible with the intended matrix which the cord will reinforce. For a rubber belt, the coating is compatible with the rubber composition of the belt body or an adhesion gum or adhesive such as RFL which surrounds the cord. For RFL/rubber systems and cast polyurethane elastomers, a suitable polymer is the APP reaction product of a vinyl carboxylic acid or an ester or amide thereof. Suitable carboxylic acids include acrylic acid and methacrylic acid. Various esters and amides of vinyl carboxylic acid are also suitable, such as 2-hydroxyethyl methacrylate, N-isobutoxymethyl acrylamide, and N-hydroxyethyl acrylamide.
1. A method comprising:
treating a carbon fiber tensile cord with atmospheric plasma polymerization process wherein the carbon fiber tensile cord is fed continuously through an afterglow plasma zone consisting of ionized air or nitrogen, and wherein a precursor selected from the group consisting of hydroxy-alkyl esters of vinyl carboxylic acids is introduced to the afterglow plasma zone in the vicinity of the carbon fiber tensile cord;
embedding the treated cord in an uncured elastomeric matrix; and
curing the matrix with the embedded cord to form a reinforced elastomeric product.
2. The method of claim 1 wherein said precursor is in the form of an aerosol in a carrier gas when introduced to the plasma in the vicinity of the carbon fiber.
3. The method of claim 1 wherein the product is selected from the group consisting of a belt, a hose, and a tire.
4. The method of claim 2 wherein the stream introducing the precursor consists of the precursor in the carrier gas.
5. the method of claim 4 wherein the carrier gas is air.
6. A method comprising:
treating a carbon fiber tensile cord with an atmospheric plasma polymerization process wherein the carbon fiber tensile cord is fed continuously through an afterglow plasma zone consisting of ionized air or ionized nitrogen, and wherein one or more precursor selected from the group consisting of lower molecule weight monomers with double bonds and containing hydroxyl functional groups that can be easily polymerized or crosslinked in the plasma is introduced to the afterglow plasma zone in the vicinity of the carbon fiber tensile cord, thus coating the carbon fiber of the tensile cord with a polymeric polymerized precursor layer deposited and polymerized at atmospheric pressure in the atmospheric plasma polymerization process;
embedding the treated cord in an uncured elastomeric matrix; and
curing the matrix with the embedded cord to form a reinforced elastomeric product.
7. The method of claim 6 wherein the one or more precursor is selected from the group consisting of hydroxy-alkyl esters of vinyl carboxylic acids.
8. The method of claim 7 wherein the one or more precursor is selected from the group consisting of 2-hydroxyethyl methacrylate, N-isobutoxymethyl acrylamide, and N-hydroxyethyl acrylamide.
9. The method of claim 6 wherein the one or more precursor is in the form of an aerosol in a carrier gas when introduced to the plasma in the vicinity of the carbon fiber.
10. The method of claim 6 wherein the product is selected from the group consisting of a belt, a hose, and a tire.
11. The method of claim 9 wherein the carrier gas is air.
12. The method of claim 9 wherein the stream introducing the precursor consists of the precursor in the carrier gas.