714 CREATIVE CHEMISTRY price of natural rubber has fluctuated from 3 cents to $1.35 per pound Plantations can make an excellent profit within the past twenty years. when natural rubber sells at between 15 and 18 cents per pound provided that shipping costs are normal. The manufacture of synthetic rubber is likely to help to stabilize the price of natural rubber. All the forms of synthetic rubber could be produced from petroleum as the main raw material, and if our total supply of rubber were produced from petroleum it would use only one third of one per cent of the annual production of crude oil. To a large extent the petroleum products used would be by-products, such as refinery gases, for which there has been little sale up to the present time. The possible production of natural rubber prior to " Pearl Harbor" was 1,600,000 tons per year, while the normal consumption was only 1,000,000 tons. This surplus of natural rubber would have increased as additional plantations came into production. Natural rubber is superior to all synthetic rubbers in regard to elasticity and rebound, extensibility, and resistance to stiffening at low temperatures. The types of synthetic rubber now available would not displace natural rubber in this country, except for specialized purposes, for a long time to come unless wars made it impossible to ship the natural rubber or other international upheavals make it impossible to obtain the rubber for other reasons. The expansion of the synthetic-rubber industry would probably follow the usual pattern unless emergency conditions change this pattern. This pattern is about as follows: 1. The introduction of a product of exceptional quality at higher prices than the products which it will replace. 2. The gradual lowering in the price and improvement in the quality as increased production and additional experience and research iron out production wrinkles. 3. New applications made possible by lowered costs and increased quality again increase production and again decrease the price until it is competitive with the price of the product which it is displacing. 4. Competition results in more research, still lower prices, and improved quality, with the result that the consumer can buy more "better things for better living." STUDY QUESTIONS 1. How do you account for Goodyear's "lucky accident"? 2. What is meant by "vulcanization of rubber"? 3. Describe some of the important new developments in the utilization of rubber. 4. Why do the automobile tires of today give much better mileage than the tires of ten or twenty years ago?
NATURAL AND SYNTHETIC RUBBERS 715 5. What are the functions and advantages of the accelerators and the antioxidants used in rubber compounding? 6. Discuss the various types of synthetic rubber as to (a) the raw materials from which they are made, (b) their properties, and (c) their uses. 7. Why are some types of synthetic rubber more resistant to chemicals, solvents, heat, and light than is natural rubber? 8. What is the usual pattern for the development of synthetic chemical industries? '