The article reports on the creation of molded products from polytetrafluoroethylene by British Mechanical Productions Ltd., such as tube holders, condensers and resistors.
Smith, Samuel, Johannessen, Birger, and Sherman, Patsy O.
Subjects
CLEANING compounds, DETERGENTS, MINERAL oils, FLUORINE compounds, POLYTEF, TEXTILES
Abstract
This study involved the measurement of the "roll-up" response of several oils on different hydrophobic films which were immersed in various test solutions of conventional and fluorine-containing detergents. The results indicated that oil roll-up could be satisfactorily explained in the systems studied by reference to the measurable surface sod interfacial energies of the liquid phases and γc the critical surface tension of wetting of the solid. Extensive oil roll-up occurred in those systems where there was a large enough disparity in the surface energy of the oil (γo) and γc to permit the selection of a suitable detergent for the system. If γo and γc values were nearly equal (e.g., perfluorooctane on polytetrafluoroethylene, mineral oil on polyethylene and tricresyl phosphate on polyester), then none of the detergents studied promoted oil roll-up. It was concluded that detergent formulation alone is very unlikely to solve the problem of effecting satisfactory release of any broad spectrum of oils from today's durable press fabrics, unless those fabrics are specially finished with hydrophilic materials. Soil release agents assure a large enough disparity between substrate γc and γo (for any common oily stain threat) so that a suitable detergent for effecting oil release may readily be selected. [ABSTRACT FROM AUTHOR]
SALES, CORPORATE profits, NEW product development, POLYTEF
Abstract
The article focuses on American company Du Pont which generated a 1,025 billion U.S. dollar sale in 1949. The figure came from a six percent gain from 1948 with profits jumping 20 percent. According to company president Crawford H. Greewalt, its growth depended on aggressive research and development of new products. The company invested 33 million U.S. dollars for research in 1949 and introduced new products including Teflon, Armalon and Alathon.
The article a simple modification of the polymer membrane electrode which has proved to be convenient for measurements of the partial pressure of carbon dioxide in the soil. The system is not suitable for following short-term fluctuations in carbon dioxide pressure and has the disadvantage that a considerable volume of carbon dioxide is lost from the soil. The device used consists of a Pyrex test tube with a hole blown in the side near the base and covered with 0-005-inch thick polytetrafluoroethylene adhesive-backed tape.