| 摘要 |
1383190 Separator for dry cell UNION CARBIDE CORP 20 Sept 1973 [21 Sept 1972] 44122/73 Heading H1B A separator comprises a layer of electrolyteimmobilizing partially cross-linked polyacrylamide supported on a layer of non-woven, bonded glass fibre web. The overall thickness of the separator is 2-7 mils. and the thickness of the glass fibre web is 1-3 mils. The cross-linking of the polyacrylamide is preferably performed by adding to an aqueous solution of the polyacrylamide a chromium-containing compound wherein a major portion of the chromium has a valence other than + 3 and a compound which reacts with the chromium-containing compound to give chromium ions at a valence of + 3, these ions producing the cross-linking. The layer of electrolyte-immobilizing partially cross-linked polyacrylamide for use in a zinc-manganese dioxide, zinc chloride cell may be formed from a composition comprising: 76À97% by weight of 5-7 weight per cent aqueous zinc chloride solution, 0À275% by weight potassium dichromate, 0À275% by weight potassium thiocyanate, 3À00% by weight polyacrylamide, 16À95% by weight talc, 2À53% by weight corrosion inhibitors. This composition is doctored on to the glass fibre web and dried by heating. The glass fibre web is formed by bonding 3À8 micron diameter and “ mil long glass fibres by a solution containing 2 to 3% by weight polyvinyl alcohol. A dry cell including the separator arranged on the inner surface of a zinc can is described with reference to Fig. 1 (not shown). |
