Rubber yielding plants: Rubber and Para Rubber plant II Properties of rubber II Free Study material II LetsBloom notes

UNIQUE PROPERTIES OF RUBBER

1. Rubber is unequaled or superior elasticity.
2. It has great imperviousness to moisture means it make it possible to not enable the entry on moisture.
3. The best rubber obtainable was appropriable to harden and crack in cold weather, and to soften or grow sticky in summer.
4. Addition of Sulphur increases its elasticity (VULCANIZATION): In 1844, Charles Goodyear, an American, announced his discovery that mixing a little sulphur in caoutchouc (natural rubber), and subjecting it to considerable heat, produces a substance that is even more elastic than pure rubber, is unchanged by any temperature up to 180 C.
5. Its imperviousness to water and air, combined with its flexibility, render it of greatest service for waterproof garments or coverings, sub¬ marine diving-dresses, flexible tubes or hose, water-bottles, life-preservers, portable boats, etc.
6. The adhesiveness of rubber is an important property.
7. The distinctive characteristic of rubber is its extreme elasticity. A curious result of this is the heat developed when a piece of it is stretched.

What is Caoutchouc?

Caoutchouc as a raw material or natural rubber extracted from plants has same relation to the milky juice of plants. It separates from the fluid part as curd from whey and becomes solid by drying.

Chemical nature

Chemically, however, caoutchouc contains only hydrogen and carbon in its composition along with various substances, regarded as impurities, among which are certain resins.

About the Plant 

• Rubber tree (Hevea brasiliensis) is a fast-growing upright tropical tree crop which is mainly cultivated for its production of latex, a milky plant liquid, which serves as a basis for various rubber products.

• Hevea brasiliens is most commonly called as the rubber tree or rubber plant, is a flowering plant belonging to the family Euphorbiaceae. It is the most economically important member of the genus Hevea because of the milky latex extracted from the tree which is the primary source of natural rubber.

• It is also known as Para Rubber Tree.

• Rubber is obtained from Latex of various plants. Most of the rubber plants belongs to Moraceae, Euphorbiaceae and apocynaceae family but Hevea plant furnish about 98% of the rubber supply.

Natural rubber is a polymer of (ICAR PG Plant Biotechnology 2022)

1. Isopentenyl units 

2. Amino acids

3. Glucose units

4. Steroid glycosides