Rubber products permeate our world. They are used extensively in automobiles, from tires to gaskets. They are used in industrial machinery and household appliances. Rubber is used in production of some articles of clothing and footwear. There are two major types of rubber: natural rubber and synthetic rubber. However, there are a variety of subordinate rubber materials, usually denoted by degrees of hardness, which can be produced from either type. Natural rubber was first discovered in the Amazon and for a time, Brazil experienced a boom from rubber production. Seeds from the rubber tree were eventually smuggled to Britain and exported to British colonies in Asia. Since the late 20th century, the majority of natural rubber has been produced in Asia, where there are vast rubber plantations. Synthetic rubber is produced across the globe.
Natural Rubber Production
The production process of natural rubber begins with the cultivation of rubber trees (Havea brasiliensis). Rubber trees must be allowed to grow for about seven years before they become viable for harvesting rubber. Once the trees have reached the appropriate level of maturity, they will be tapped. Tapping generally occurs every two to three days, but never more often than once per day. The tapping process involves stripping away a small section of bark at a slight angle to facilitate latex drainage. The same area of the tree can be tapped repeatedly. When a particular area of the tree is tapped out, a new portion of the tree will be tapped. It generally takes seven years for a tapped area to heal sufficiently to be tapped again. A tree will normally produce about half a cup of latex per day. Once the latex has been collected, it will be mixed with a diluted acid. The rubber/acid mixture is then rolled twice. The first rolling is to remove excess water. The second rolling is to texture the rubber. The rubber is dried and can then be sold or exported.
Synthetic Rubber Production
Synthetic rubber production begins with the refining of oil, coal or other hydrocarbons. During the refining process, naphtha is produced. The naphtha is collected and can then be combined with natural gas to produce monomers such as styrene and isoprene, which are necessary for the production of synthetic rubber. The monomers are then generally subjected to either an emulsion polymerization process or a solution polymerization process. In both cases, the idea is to create chains of polymers which results in a latex or rubber substance. These substances can then be processed into useful rubber products using techniques such as vulcanization, which is used to produce rubber for tires.