VOL.9, No. 6 RECENT DEVELOPMENTS IN RUBBER INDUSTRY .
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Previous Articles on Rubber Appearing in the Journal of Chemical Education BERGENER, H. D., "The Relation of Chemistry t o the Ruhher Industry" (firize essay), J. CHEM.Enuc., 6, 125944 (July-Aug., 1929). BRAUER, 0 . L., "The Outlook for Synthetic Rubber," ibid., 6, 1286-92 (July-Aug., 1929). Cox, M., "Chemistry in Relation to the Rubber Industry" (prize essay), ibid., 3, 104450 (Sept., 1926). (Dec., 1929). DALES,B., "The Electrodeposition of Rubber," &id., 6, 223F I S ~ E RH. , L., "Rubber: Newer Theoretical and Practical Developments," ibid., 8, 7-29 (Jan., 1931). "The Chemistry of Rubber," ibid., 3,253-66 (Mar.. 1926). KELLYAND BRUSON. LAWRENCE. . -1. C.. . "Pioneers in the Commercial Develo~mentof Rubber." ibid., 7, 1788-801 (Aug., 1930). McPnERsoN, A. J., "Redaimed Rubber" (Circular of the Bureau of Standards), iM., 8, 2478 (Dec., 1931). TAnoR. B. S.. "The Chemist in the Rubber Plant," ibid., 8. 1829-38 (Sept., 1931). WATERS,C. E., "The Work of the Bureau of Standards on Rubber." ibid.. 3,291-5 (Mar., 1926). TRIPLEX RUBBER FOR TANKS FOR STEEL PICKLING Fundamental advances in design of tanks for steel pickling have been announced recently by the B. F. Goodrich Company, Akron, Ohio. Using TriRex rubber, adhered by the patented Vulcalock process, and protective sheathings of wood or brick, the new development affords structwal strength and permanence hitherto unattainable in pickling work. Triflex is a new form of rubber lining especially designed to meet the severe conditions encountered in pickling. In the new Triflex const~uctiona layer of hard rubber is cushioned between two layers of soft rubber. The hardrubber serves t o resist penetrating and deteriorating effects of acids, oils, and oxidation, and also imparts its mechanical strength and stiffness to the lining. The soft rubber layers serve t o cushion the hard layer from the effects of sharp blows. Special expansion joints are provided which absorb strains incident to expansion and contraction with temperature changes, effectively preventing distortion and crackling of the hard rubber. Triflex thus combines advantages of both hard and soft rubber and eliminates, through sound engineering practice, apparent weaknesses of both. This three-ply construction has proved remarkably immune to physical damage to shock, impact, or gouging. Actual resistance of Triflex to impact is nearly 100 times that of ordinary rubber linings. In addition, Triflex combines resistance of true hard rubber to chemical and solvent action, diffusion, and absorption, with the resilience and wear-resisting qualities of the soft rubber face layer. Relative thickness of the three plies may be vsried within rather wide limits to obtain desired properties for each type of service. Sudden variations in temperature, which are often hazardous t o ordinary hard rubber linings, have no adverse effect on the three-ply construction with expansion joints. The Vulcalock process is used exclusively by Goodrich for bonding soft, acid-proof resilient rubber t o metal. It insures practically integral adhesion between rubber and steel to withstand a minimum rip-shock of 500 pounds per square inch. Brick or wood sheathings are installed t o insure freedom from damage t o the rubber through gouging or impact of heavy steel parts. Brick sheathings also have the merit of lowering the temperathre a t the rubber surface to a point where effects of acid and oxidation are negligible.
