Patent GB-825105-A (GB)
Title: Improvements in or relating to cork compositions
IPC: B27J5/00
Filed: 1957-05-21
Abstract: A binder for a cork composition comprises the reaction product of (a) an epoxy resin containing terminal epoxy groups, and (b) a polymeric polyamide resin which is the reaction product of polymeric fatty acids containing at least two carboxyl groups and an aliphatic polyamine, the polyamide resin containing free groups selected from amine groups and carboxyl groups.  The epoxy resins are reaction products of polyfunctional halohydrins, e.g. epichlorohydrin and glycerol dichlorohydrin, with polyhydric phenols, e.g. resorcinol and bisphenols resulting from the condensation of phenol with aldehydes and ketones such as formaldehyde, acetaldehyde, acetone, and methyl ethyl ketone.  The polymeric fatty acids referred to under (b) result from the polymerization of drying or semi-drying oils or the free acids separated from the oils or simple aliphatic alcohol esters of such acids, suitable oils being soya bean, linseed, tung, parilla, oiticica, cotton seed, corn, tall, sunflower, safflower, and dehydrated castor oil.  Typical polyamines specified under (b) are ethylene diamine, diethylene triamine, triethylene tetra-amine, tetra ethylene pentamine, 1,4 - diaminobutane, 1,3 - diamino butane, hexamethylene diamine, 3 - (N - isopropyl amino) propylamine, and 3,31-amino-bispropylamine.  The ratio by weight of epoxy to polyamide resin in the binder is from 10:90 to 70:30, the binder forming 5 to 300% by weight of cork.ALSO:A cork composition comprises cork granules and a binder therefor, the binder comprising the reaction product of (a) an epoxy resin containing terminal epoxy groups, and (b) a polymeric polyamide resin which is the reaction product of polymeric fatty acids containing at least two carboxyl groups and an aliphatic polyamine, the polyamide resin containing free groups selected from amine groups and carboxyl groups.  The epoxy resins are reaction products of polyfunctional halohydrins, e.g. epichlorohydrin and glycerol dichlorohydrin, with polyhydric phenols, e.g. resorcinol and bisphenols resulting from the condensation of phenol with aldehydes and ketones such as formaldehyde, acetaldehyde, acetone and methyl ethyl ketone.  The polymeric fatty acids referred to under (b) result from the polymerization of drying or semi-drying oils or the free acids separated from the oils on simple aliphatic alcohol esters of such acids, suitable oils being soy bean, linseed, tung, parilla, oiticica, cotton seed, corn, tall, sunflower, safflower and dehydrated castor oil.  Typical polyamines specified under (b) are ethylene diamine, diethylene triamine, triethylene tetra-amine, tetraethylene pentamine, 1, 4-diamino butane, 1. 3-diamino butane, hexamethylene diamine, 3-(N-isopropyl amino) propylamine, and 3, 31 -amino-bispropylamine.  The ratio by weight of epoxy to polyamide resin in the binder is from 10 : 90 to 70 : 30, the binder forming 5 to 300% by weight of cork. Plasticizers for the cork include polyhydric alcohols e.g. glycerine, ethylene glycol, diethylene glycol and triethylene glycol, and higher alcohols, e.g. sorbitol, the plasticizers forming 5 to 40% by weight of cork.  To facilitate cutting the cork composition, a non-drying hydrocarbon oil, preferably a paraffin mineral oil, may be added in a proportion of 5 to 30% by weight of cork.  Pigments and/or dyes and inert fillers, e.g. ground walnut shells, wood flour, clays and earths can also be added.