Rubber Tree Bark Research Articles

Anode Process for Rubber Articles and Coatings

Abstract THE term “anode process” has been chosen and used widely in the trade to designate a fundamental method for the production, directly from rubber latex, rapidly, and in one application, of articles and coatings of the highest grade of unmasticated rubber. Rubber latex, a milky exudation from the bark of rubber trees, is composed chiefly of tiny particles of rubber suspended in a water phase or serum, not unlike globules of butter fat in milk. Rubber latex contains small amounts of many organic compounds and inorganic salts. Some of these non-rubber materials, such as the proteins and resins, are considered to be adsorbed on the surfaces of the rubber particles and to be responsible for many of the colloidal characteristics of latex. As it comes from the tree, the latex is unstable and coagulates easily, but, when stabilized with ammonia, it can be safely shipped and stored for long periods. Like most colloidal particles in suspension in an alkaline medium, the rubber particles of ammoniated latex are negatively charged through the adsorption of hydroxyl anions. The particles, many as small as 1/25,000 inch in diameter, are in constant oscillation (Brownian movement) and are kept from hitting one another and sticking together (coagulating) by the repulsion of their electric charges. When the hydroxyl ions are neutralized or otherwise removed from the particles, the electric repulsion between particles disappears and coagulation results.

PINK DISEASE OF PLANTATION RUBBER.

SUMMARY The distribution, hosts, and mode of action of Pink Disease are described and its importance as a disease of plantation rubber is emphasised. The various forms of Corticium salmonicolor are described. It is pointed out that the fungus is not a typical Corticium and that the pink incrustation is very frequently sterile. Corticium salmonicolor often affects the wood as well as the bark of rubber trees. Its action on the wood is described in detail. The formation of tyloses appears to be a response to the presence of the fungus in the wood. Pure cultures of Corticium salmonicolor have been established on salep agar and on Hevea wood. Inoculation experiments both with natural material and with the fungus grown in pure culture have been successful. Treatment, (a) Spraying is not recommended except in particular cases, (b) The disease is best dealt with either by cutting out infected branches, or by treating affected parts with tar. Detailed instructions are given as to the manner in which these operations should be carried out by a pest gang.