Patent GB-663072-A (GB)
Title: Improvements relating to compositions comprising organic thermoplastic substances
IPC: C08K5/10
Filed: 1949-05-20
Abstract: Compositions comprising an organic thermoplastic substance include as solvent or as plasticizer a monomeric simple or mixed dicarboxylic acid ester of 1 : 4-butane-diol in which each of the acid esterifying groups is aliphatic, alicyclic - substituted aliphatic or heterocyclic in nature and contains no aromatic group, or each contains an aromatic group or groups and is free from ethylenic and acetylenic unsaturation.  Thermoplastic substances mentioned are cellulose derivatives such as the nitrate, acetate, propionate, butyrate, acetate propionate, acetate butyrate, ethyl cellulose or benzyl cellulose, polyvinyl chloride, copolymers of vinyl chloride and vinyl acetate or vinylidene chloride, polystyrene and copolymers of styrene and 1 : 3-butadiene.  Representative of 1 : 4-butanediol diesters mentioned are the diacetate, di-(2-ethyl hexoate) acetate cyclohexylacetate, phenylacetate phthalate and distearate.  In examples: (1) the diacetate is a solvent for cellulose acetate; (2) the di-(2-ethylhexoate) is used to plasticize cellulose propionate which is moulded; (3) the di-(chloroacetate) is a solvent for cellulose propionate; (4) the dipropionate is used to plasticize cellulose propionate and acetate, which are moulded; (5) the difuroate is used to plasticize cellulose propionate which is moulded; (6) the di-(cyclohexylacetate) is used to plasticize cellulose propionate; (7) di-(cyclohexylcaproate) is used to plasticize cellulose propionate which is moulded; (8) the dilaurate is dissolved in petroleum ether and mixed with ethyl cellulose which after evaporating the petroleum ether, is moulded.  The esters of 1 : 4-butanediol are prepared using tetrahydrofuran as starting material or by ester interchange (see Group IV (b)).  Vinyl ethyl acetate (CH2=CH-CH2CH2-O2C-CH3) obtained as a by-product in preparing 1 : 4-butanediol diacetate from tetramethylene oxide and glacial acetic acid, is a solvent for cellulose derivatives, polyvinyl chloride, copolymers of vinyl chloride and vinyl acetate and other polymers. Specification 594,378 is referred to.ALSO:Simple or mixed di-carboxylic acid esters of 1 : 4-butane diol in which each of the acid esterifying groups is aliphatic, alicyclic-substituted aliphatic, or heterocyclic in nature and contains no aromatic group, or each contains an aromatic group or groups and is free from ethylenic or acetylenic unsaturation and which are employed as solvents or plasticizers in compositions comprising thermoplastic substances (see Group IV (a)) may be prepared by either (a) heating tetramethylene oxide with a carboxylic acid or anhydride or a mixture of two such acids or anhydrides in the presence of anhydrous aluminium chloride, concentrated sulphuric acid, concentrated phosphoric acid or anhydrous zinc chloride; or (b) by ester interchange between a carboxylic acid of higher molecular weight and a 1 : 4-butane diol ester of a carboxylic acid of higher volatility, particularly acetic, propionic or butyric acid.  Mixed esters may be obtained in process (a) by using a mixture of acids or anhydrides, and in process (b) by using equimolecular proportions of di-ester and replacing acid.  In process (a) the reactants may be heated together, or the tetramethylene oxide may be added to the heated acid or anhydride under reflux, at atmospheric pressure, or heating under pressure may be employed, and in process (b) a basic or salt esterification catalyst may be employed but an acid catalyst such as sulphuric acid is preferred.  1 : 4-Butane diol esters mentioned are the diacetate, dichloracetate, dipropionate, di-butyrate, di - (2 - ethylhexoate), di - laurate, di - (cyclo - hexyl - acetate), acetate cyclohexyl-acetate, di - (3 - cyclohexyl - butyrate), di-furoate, di-benzoate, di-phenyl-acetate, di-phthalate, acetate butyrate, acetate propionate, phenylacetate phthalate, acetate stearate, di-stearate, acetate 3-cyclohexyl-butyrate, acetate omega-cyclohexyl-caproate, di-(omega-cyclohexyl-caproate) and p acetate furoate.  By process (a) are prepared in examples (1)-(4) the diacetate, di-(2-ethyl hexoate), the dichloracetate and dipropionate, using tetramethylene oxide and acetic acid, 2-ethyl hexoic acid and propionic acid respectively, in the presence of freshly fused zinc chloride, and by process (b) in examples (5)-(7) the difuroate, the dicyclohexylacetate and both acetate (cyclohexyl-caproate) and di-(cyclohexyl-caproate) from the diacetate and furoic, cyclohexyl acetic and cyclohexylcaproic acids, respectively, using sulphuric acid as catalyst. Vinyl-ethyl acetate (CH2=CH-CH2CH2O2CCH3) is obtained as a by-product in example (1).  Specification 594,378 is referred to.  The Specification as open to inspection under Sect. 91 comprises also the preparation by process (a) from tetramethylene oxide and benzoic anhydride and lauric anhydride respectively of the dibenzoate and dilaurate and by process (b) the preparation of the acetate stearate from the diacetate and stearic acid.  This subject-matter does not appear in the Specification as accepted.