Improvements in or relating to esters of dipentaerythritol and to methods of producing same

摘要

556,829. Paints. STEVENS, A. H. (American Cyanamid Co.). Aug. 12, 1941, No. 10255. [Class 95] [Also in Groups IV and V] Dipentaerythritol esters are produced by heating dipentaerythritol with a mixture of unsaturated fatty acids obtained from a natural drying or semi-drying oil as the sole acidic esterifying agent. When the esterification is not complete the incompletely esterified products may be separated from the completely esterified portion by extracting with a lower aliphatic alcohol. As sources of the fatty acid mixtures many oils are listed. The completely esterified products have good drying properties and the product with three esterified groups is compatible with many resinous and plastic materials such as urea formaldehyde and melamine formaldehyde resins, ethyl cellulose and rubber derivatives both in solutions and in films. For example, it is compatible with polystyrene in xylene, cellulose acetate butyrate in methyl ethyl ketone, cellulose nitrate in toluene methyl ahydroxy butyrate mixture, and with chlorinated rubber in xylene. The dipentaerythritol esters are suitable for varnish making by heating with ester gum, phenol formaldehyde resins, or natural resins such as copal and dammar. Thus a source of abietic acid such as gum rosin may be heated with dipentaerythritol to form a neutral ester, which is then heated with a dipentaerythritol ester of soya or linseed oil acids. In examples (1) dipentaerythritol is heated with soya acid, and the product shaken with ethyl alcohol to remove unreacted acids and mono esters; the product is made into a paint with white lead titanium oxide, zinc oxide, talc and oil; (2) and (3) esters of linseed oil, dehydrated castor oil, tung oil, and castor oil acids are prepared similarly, the properties of the products being tabulated; (4) dipentaerythritol is esterified with half the theoretical quantity of soya acids and the product is added to melamine formaldehyde resin in butanol, xylene being added, and to a butylated urea formaldehyde resin in butanol and xylene.