Historical outlines on rubber
The first news that we have regarding rubber in Europe date back to the beginning of the XVI century, when some Spaniards returning from the "New World" refer to a substance that the natives obtained from a plant that grew in the rain forests: the caoutchouc.
This substance did not immediately find a use in production in Europe, it was too difficult to work and too sensitive to variations in temperature; it had not yet shown its special capabilities. It was not until the beginning of the 1800s that the large-scale utilisation of natural rubber that was imported from the plantations of South America began.
Its principal use became the preparation of impermeable garments; it had in fact been discovered that carbon naphtha had the property of dissolving the rubber, so that it could be spread. Impermeable fabrics were realised by applying a layer of rubber between two layers of fabric.
Towards the middle of the XIX century a procedure was discovered by the Englishman Thomas Hancock that would change the history of rubber: mastication. Mastication involved the tearing of blocks of raw rubber by means of organs equipped with points. The product obtained in this manner was much easier to work than raw rubber. A few years later, the process known as "vulcanisation" was discovered; vulcanisation confers greater stability to thermal variations to the rubber, allowing it to conserve its characteristics for a wider interval of temperatures.
The first vulcanisation processes involved the immersion of masticated rubber leaves in baths of melted sulphur. The perfecting of these new processing systems lead to the birth of the rubber industry, which developed rapidly in the second half of the XIX century.
The studies on the nature of rubber that scientists carried out in '800, the discovery of its empirical formula and the composition of its molecular chain, were the basis that lead to the realisation of the first synthetic rubbers that appeared at the beginning of the XX century.
The production of synthetic rubber begins with the gleaning of a base monomer from which the rubber for polymerisation is obtained. In 1910, some Russian chemists had already synthesised polybutadiene, giving rise to the birth of the Soviet synthetic rubber industry, one of the most important at the beginning of the century. At the same time in Germany, methylic rubber began to be synthesised and produced, and a few years later so was rubber based on styrene and butadiene copolymers. With the beginning of the first synthetic rubber production industries in the United States, its use reached world proportions, affecting the domination that natural rubber had had until then. Oils, carbon and other additives were added to synthetic rubbers with the aim of making them even easier to process and in order to obtain types of rubber suitable for new and complex uses. The advantages of synthetic rubber as compared to natural rubber were essentially represented by the greater level of purity and greater workability with respect to a product of vegetable origin with variable grades of purity and changing chemical and physical characteristics, linked to the region of origin and the period of production. With the influence of synthetic rubber, natural rubber also improved qualitatively and quantitatively, thanks to the use of technology created for the production of their synthetic counterparts. A very important step for the diffusion of rubber took place midway through the XX century, when Du Pont put the first Fluorocarbon rubber on the market, with the Viton trade mark.
Due to its characteristics of high resistance to physical stress and chemical aggression, fluorocarbon rubber is still a product that is very much in use today for the realisation of elements in moulded rubber, and in particular for the realisation of gaskets. Today, thanks to enormous developments in rubber technology, we have at our disposal a huge quantity of compounds to use for the realisation of products of any form, suitable for all applications, from biomedicine to aerospace.