Patent GB-782894-A (GB)
Title: Cadmium salts of alpha-hydroxy fatty acids, their preparation and resins stabilised with said salts
IPC: C07C51/41
Filed: 1954-02-12
Abstract: Cadmium salts of a -hydroxy fatty acids having 8 to 18 carbon atoms, particularly those containing not more than 5 per cent of self ester (see Group IV (b)), are used as stabilizers for halogen-containing synthetic resins, such as polyvinyl chloride and copolymers of vinyl chloride with vinyl acetate.  Suitable resins are described in Specification 694,944.  Examples of a -hydroxy fatty acids which may be employed as their cadmium salts are a -hydroxy capric acid, a -hydroxy caprylic acid, a -hydroxy lauric acid, a  - hydroxy palmitic acid, a  - hydroxy stearic acid, a  - hydroxy - 4,6,6 - trimethyl heptanoic acid and a -hydroxy-a -ethyl-hexoic acid.  They may be added before, during or after polymerization and are preferably incorporated in the polymerized resin before compounding it in the rubber mill.  The stabilizers may be used in combination with other stabilizers such as salts of barium, strontium, calcium, zinc, tin or other metals, epoxy compounds such as glycidyl ethers of phenols and diphenols, e.g. phenyl glycidyl ether, octyl phenyl glycidyl ether, glycidyl ether of dimethyl dihydroxy phenyl methane; esters of epoxidized alcohols, e.g. glycidyl oleate, and glycidyl naphthenate; epoxidized esters such as 9,10-epoxymethyl stearate, epoxidized soya oil, epoxidized ethylene glycol distearate; epoxidized hydrocarbons such as styrene oxide, diisobutylene oxide or stilbene oxide; esters of phosphorous acid such as triethyl, tributyl and trioctyl phosphites; phosphorous acid esters of phenyl phenol and other substituted phenols; mixed aliphatic-aromatic phosphites and polymeric phosphites prepared from phosphorus trichloride and phenols such as p-tert. butyl cresol, octyl phenol, partial ethers of hydroquinone, resorcinol, catechol and pyrogallol.  The stabilizers are compatible with the usual plasticizers, e.g. dioctyl phthalate and phosphoric esters of aliphatic alcohols and/or phenols, or mixtures thereof, such as tributyl, trioctyl, tricresyl and diphenyl octyl phosphates.  The stabilized vinyl chloride polymer compositions may be in the form of a plastisol.ALSO:The invention comprises cadmium salts of a -hydroxy fatty acids having 8 to 18 carbon atoms, particularly those containing not more than about 5 per cent of self ester.  The salts may be prepared by neutralizing an a -hydroxy fatty acid having 8 to 18 carbon atoms with an amount of alkali sufficient to neutralize the acid and to saponify any self-ester present in the acid, and adding a water-soluble cadmium salt in an amount not exceeding the stoichiometric equivalent of the acid.  Suitable a -hydroxy fatty cids are a -hydroxy capric acid, a -hydroxy caprylic acid, a -hydroxy lauric acid, a -hydroxy palmitic acid, a -hydroxystearic acid, a  - hydroxy - 4,6,6 - trimethyl - heptanoic acid, and a  - hydroxy - a  - ethyl - hexoic acid. Such acids may be prepared by reacting an aldehyde with hydrogen cyanide and saponifying the cyanhydrin, or by alkaline hydrolysis of the corresponding a -bromo fatty acid.  In examples: (1) a -bromolauric acid, obtained by bromination of lauric acid, is refluxed with caustic soda and the mixture is acidified to obtain a -hydroxy lauric acid which is then neutralized with caustic soda and mixed with aqueous cadmium chloride solution to give the cadmium salt; (6) barium-cadmium a -hydroxy laurate is obtained from the sodium a -hydroxy laurate (obtained as above described) by coprecipitation with a mixture of barium and cadmium chlorides.  The novel compounds are useful as stabilizers for halogen-containing synthetic resins (see Group IV (a)).