| 摘要 |
1,247,719. Carbon electrodes. UNION CARBIDE CORP. 30 Dec., 1968 [29 Dec., 1967], No. 61595/68. Heading C1A. [Also in Division H1] A carbon electrode is rendered electrolyte repellant without substantially lessening its gas permeability by treating its active surfaces with a polyterpene resin. The electrode may comprise carbon particles united with a binder and backed by a metal screen. The resin may be derived from alpha- or beta-pinene, e.g. by converting alpha-pinene to dipentene and polymerizing this. It may have a softening point from 55-115‹ C., a molecular weight of about 1,200 and a saponification number of less than 1À0 and may be soluble in alcohols, ketones, chlorinated hydrocarbons and solvents derived from petroleum. A 0À5-25% solution of the resin in toluene, xylene, benzene, kerosene or ethylene dichloride may be warmed or maintained at room temperature whilst the electrode is immersed in it for from 5 sees. to 1 hour. On removal the electrode may be heated for 5-8 hours to remove the solvent. The resin may then be present throughout the whole electrode body. |
