Rubber is derived from processing latex, which is obtained by sectioning the bark of a typical Amazon tree, the Hevea brasiliensis.

It is an elastomer, that is, a polymeric material of natural or synthetic origin characterized by its great elasticity. This quality consists of the ability to deform significantly when external force is applied and return to its original shape.

Today, much of the use of natural rubber has been replaced by synthetic rubbers, produced through industrial processes that allow for the creation of products with the same performance but at a much lower cost.

History of Natural Rubber

For years, production was the sole prerogative of the Amazon basin, and this was one of the reasons why many Europeans speculated on Brazilian plantations.

Natural rubber was already known in Europe by the mid-19th century, but it only came from South American plantations.

It wasn’t until the 20th century that plantations also began in Southeast Asia, where the humid climate was also favorable.

The invention of vulcanization, often attributed to American Charles Goodyear and dating back to 1844, helped spread its use. In fact, latex is unusable without this process because:

• It is sticky when exposed to the sun and disintegrates at high temperatures.
• It is very brittle at low temperatures.
• It turns brown and coagulates when kept in the air.

Thus, until a few decades ago, it was the only rubbery and elastic material on the market.

Liquid Rubber Processing

After harvesting, the liquid rubber is filtered, diluted with water, and mixed with a series of substances to improve mechanical and abrasion resistance, particularly carbon black (which is why rubber products are often black). If the black color is to be avoided, white additives like precipitated silica, clay, or precipitated gypsum are used.

These chemical treatments modify its structure, making it resistant and elastic, as it is initially very sensitive to temperature changes and light:

• It softens with heat.
• It hardens with cold.
• Its color changes when exposed to direct light.

Vulcanization

To stabilize natural rubber and make it more resistant, a process called vulcanization with sulfur is carried out, a process introduced in 1840 and used in the manufacture of our rubber tips.

The costs of transforming natural rubber are high, so over the years, the consumer product industry has increasingly opted for synthetic rubber as a substitute for natural rubber, which is environmentally friendly.

However, it should be noted that synthetic rubbers are made from petroleum and are not environmentally friendly. On the other hand, rubber is a natural material that is completely biodegradable at the end of its life cycle.

Biodegradable Rubber

Natural latex is itself biodegradable and safe for the environment, but the substances it is treated with, such as ammonia, tetramethyl disulfide, and zinc oxide, used as preservatives against bacterial decomposition, make it difficult to recycle.

In fact, wastewater treatment plant operators report that latex is one of the many harmful materials that is not affected by the biological treatment system.

Therefore, the resulting products are difficult to recycle. At present, no technique has been found to reuse it while retaining all its qualities.

However, it can be used to make less elastic products with lower purity requirements.

In addition, it can also be used as fuel in cement factories and some power plants, and the “powder” made from recycled rubber granules, particularly from used tires, is applied to improve the appearance, flexibility, and stability of artificial turf sports fields.