The process of vulcanization, invented by Charles Goodyear in 1839, made rubber more stable by cross-linking sulfur bonds.
Despite extensive research, vulcanization has historically been a non-reversible process with the result that it has not been possible to re-use vulcanized rubber in the production of new rubber products.
De-vulcanization is the reverse of the vulcanization process. As shown in the diagram to the right, the sulphur bonds are opened up and the chemical characteristics of the de-vulcanized material now resemble virgin rubber.
The DeLink reactant is a proprietary and patented chemical mixture comprised of chemicals used commonly in the rubber industry.
The process is a mechano-chemical reaction in nature, in that it requires mechanical shear to expose fresh crumb surfaces so that the DeLink reactant can effectively uncouple the sulphur cross links in the polymer chain.
The process takes about 8 minutes.
The crumb is the product of breaking down waste rubber, in a crumbing plant, into small particles of about 30 mesh size. The process is performed using standard rubber processing machines such as high shear mills, refiners and internal mixers.
The resulting material is further treated, to stabilize certain reactive properties, to yield Green Rubber, which closely retains the properties of the original virgin rubber compound. Green Rubber may be re-vulcanized without the addition of any further curatives or blended with virgin rubber compounds for use in a wide variety of commercial rubber based products.
It should be noted that mixtures used for making rubber products are often highly complex and are definitely not just rubber and a few curative chemicals.
For instance, a steel belted radial tire typically contains different natural rubbers, several synthetic rubbers, carbon black, polyester and nylon fiber, steel cords and about 40 chemicals. The process of crumbing strips out the steel and removes fiber. The resulting rubbers and chemicals are processed with DeLink.
DeLink works effectively with both natural and synthetic rubbers.
Charles Goodyear revolutionized the rubber industry in 1839 by inventing vulcanization.
Green Rubber Global finishes the job by making de-vulcanization possible â€“ and making the rubber truly recyclable.