Text A

Polymers in use

In the field of organic chemistry it may be said that we are living in a "plastics age". Many articles formerly constructed of metal, wood, rubber or leather have been replaced by plastics,

The use of plastics in home construction1 automobiles, boats, airplanes and consumer goods has increased tremendously in the past few years. The superior properties of many plastics have resulted in the increased application of plastics in the electrical, radio, television and chemical industries. Plastics, synthetic rubbers, man-made fibres and films belong to a class of compounds called polymers. This means the molecules of these materials are very big, consisting of a huge number of atoms and with molecular weights that are enormous compared to those of ordinary materials.

Today there exists a great number of plastics materials and this number is being increased as new polymers are discovered. Polymers have made a significant contribution to some of the newer technologies. For example, the development of electronics depended considerably upon polymers for their excellent electrical insulating properties. The computer is another symbol of our age and computers are now being used to control the chemical processes that produce the polymers. The polymers, in turn, are being employed in the electrical circuits" that constitute the heart of these machines.

Polymers have also played their part in the modern system of telecommunication and our ability to lift a telephone receiver in Kyiv and speak to somebody in New York is due to the use of special plastics in the submarine cables.

A great deal of research had been carried out before special grades of polymeric materials were obtained for space technology. Now they are in vide use in space vehicles because of their combination of light weight with the ability of performing certain functions. One of their uses is as protective coatings for spaceships to protect them from burning up as they reenter the earth's atmosphere. The problem arises because at the very high speeds of reentry great heat is generated by air friction. No solid material can withstand these temperatures, sometimes of several thousand degrees Centigrade

Land vehicles have also changed due to the use of polymers. Vehicles are nearly all painted and therefore have, at least, a surface coating of these materials. Car bodies made of polymeric materials offer not only considerable

saving in weight but also good ease in repairing.

Building is another activity which makes extensive use of polymers. The latter have brought a new look to floors, walls, ceilings and furniture. In the field of domestic appliances polymers are finding increasing opportu­nity especially through man-made fibres. Today synthetic fibres made from various polymers are being used in products varying from ropes and nets to fine textiles.

Grammar and lexical exrecises I.

I. Translate the sentences paying attention to the Gerund.

1.I know of his having been sent to work to the Far East. 2. What is the reason for his having left our city so suddenly? 3. We heard of the experiment having been started last week. 4. He improved his report by changing the end. 5. They objected to his remaining at home. 6. Instead of restoring the old theatre they decided to build a new one in the centre of the town. 7. New possibilities for applying atomic energy open up. 8. It is possible to set up power stations based on utilizing the heat of the sun. 9. The idea of creating a multi-stage rocket belongs to Tsiolkovsky. 10. Before having been sent up the balloon was filled with a special gas. 11. What apparatus do we use for measuring air pressure? 12. Science requires experimenting. 13. These methods were tried without obtaining the necessary results. 14. Speaking foreign languages is of importance for every cultured man.