Natural Latex as a Colloidal System

Abstract

Abstract Natural rubber latex as a raw material for industry is relatively young. Although solid rubber has been known ever since the days Christopher Columbus and his men marvelled at the natives of Haiti playing with a ball made from the gum of a tree—which was in 1496—latex received little attention until the third decade of the twentieth century. By that time the rubber plantation industry had developed to such an extent that it appeared feasible to collect, preserve and transport latex on a large scale. Malaya was the first to export latex in commercial quantities in 1922, followed by Indonesia in 1926 and by Liberia in 1935. At the outbreak of World War II annual world production of latex had reached 44,000 tons but it was not until 1948 that production was back at the same level again. The last ten years have shown a rapid increase with world production reaching 168,000 tons in 1957. This would not have been possible without the application to manufacturing of scientific methods which in turn were based on an ever increasing amount of fundamental knowledge of its properties. It is well known that natural latex, as a liquid of biotic origin, may at times show considerable variations in composition and colloidal structure as the result of biotic, geotic, cilmatic and other influences. It is these differences which account for the variability in the properties of latex and rubber, a variability which is sometimes the cause of difficulties in processing these materials to a product of well defined and uniform properties. Great strides have been made over the last twenty years and it is the purpose of this review to outline the principal facts regarding natural latex as a colloidal system and to indicate the progress made in this field of research.