Vulcanized Rubber Information
Vulcanization is an irreversible biochemical process by which natural rubber (chemically named as ‘polyisoprene’) from the latex (a white milky liquid extracted from the rubber trees) is made more tough and durable by synthetically adding sulphur or similar kinds of curatives (chemicals which act as remedial agents increasing the lasting time of the substrate on which it is applied). The product so formed after vulcanization is commercially known as ‘cured rubber’ or more specifically vulcanized rubber. It is actually named after the Roman God of the smiths called ‘Vulcan’.
The first vulcanized rubber was produced in the nineteenth century which was the successful invention of Charles Goodyear and Thomas Hancock. Later with the break through discovery of more efficient curators by George Oenslager in the year of 1905, better quality of vulcanized rubber captured the global market just within a few years. Most of the rubber trees are found in Malaysia and a few other nations in the eastern part of Asia. Very few rubber productions come from the rest of the world.
The basic process of vulcanizing natural rubber can be well explained in simple words. At very high temperature and pressure, the polymers (long chains of molecules) of liquid natural rubber are modified into long chains of polymers. This is done using the sulphur additives which form cross linkages (macro molecular bridges) with the natural polymers of rubber. Each cross link consists of eight sulphur atoms between two long polymeric chains (isoprene branches). This decreases the sticky nature of the natural rubber and hence enhances the mechanical strength and durability of it. The sulphur cross links prevent the rubber polymers to slide on top of the others. This eventually increases the elasticity to a high degree. Thus called vulcanized rubber (or cured rubber). Controlled cross linking creates better quality rubber. The density and amount of the curing agents depend on the substrate and the final product application. The most common vulcanizing agent is sulphur. Vulcanized rubber can also be produced by using other additives like peroxides, urethane cross linkers, metallic oxides etc.
It is the vulcanized rubber which finds vibrant uses in the modern industrial world. Some of the irreplaceable uses of this rubber include vehicle tires, shoe soles, hoses of pipes, erasers, hockey pucks, door stoppers, chair scratch guards, rubber washers, balls, pads etc. Very hard vulcanized rubber is termed as ebonite or vulcanite. Long ebonite rods find vast array of uses in clarinet mouth pieces, bowling balls, static electricity determinations etc.
There are a number of advantages of vulcanized rubber over the natural one. Prominently, it is highly elastic, stronger (as already mentioned), does not deform easily when warmed, less sticky, less brittle under cold temperatures and more rigid than natural rubber. These are only to name a few of the bright sides of vulcanized rubber. Like all other things in spite of a number of promising advantages, it too suffers from a hell lot of shortcomings. Though to some extents the deformation is resisted in vulcanized rubbers at higher temperatures, yet it cannot be heated to remain stable beyond a limit. This puts a bar on its uses and hence limits the industry application areas of vulcanized rubber.
So in a nutshell, vulcanized rubber is a better durable and more rigid form of natural rubber which is formed by a chemical process in presence of additive agents, the most popular being sulphur. The invention of vulcanization of rubber finds a debatable position in the history of world’s scientific innovations. So, the credit of discovery is jointly paid to both the inventors for their independent efforts. Rubber in the vulcanized form is more acceptable industrially, than the natural rubber. With the many uses of it, there are a few limitations as well. The process of producing higher quality of the product is continually under progression.