Patent GB-886410-A (GB)
Title: Improvements in and relating to spirobi-m-dioxane compounds
IPC: C08G59/50
Filed: 1958-12-24
Abstract: Linear condensation polymers are prepared by polymerization of spirobi-m-dioxane di-acids, di-esters, ester-nitriles and di-nitriles of the general formula:-  <FORM:0886410/IV (a)/1> wherein R and R1 each designate a divalent aliphatic radical CnH2n,n being an integer from 2 to 18, the divalent cyclohexane residue or the divalent, 2,5-endomethylene cyclohexane residue and X and X1 both represent carbonyl radicals or each designate a -CN or -COOR2 radical wherein R2 is a C6-9 alkyl radical or a C1-14 monocyclic aryl hydro carbyl radical, X and X1 being separated from the carbon atoms in the 3- and 9-positions by at least 2 carbon atoms.  Vinyl chloride resins are plasticized by means of monomeric di-esters of the above general formula.  Specified resins are polyvinyl chloride and vinyl chloride copolymerized with vinyl esters of lower alkanoic acids.  In an example, a vinyl chloride-acetate copolymer is plasticized with 3,9-bis(carboxypropyl)-2,4,8,10-tetraoxaspiro (5,5) hendecane admixed with a lead phosphate and lead stearate.  Epoxy resins are cured by means of diamines and amino-esters obtained by hydrogenation of the monomeric di-nitriles and nitrile esters of the above formula.ALSO:The invention comprises spirobi-m-dioxane diesters, dinitriles, ester-nitriles and diacids of of the general formula <FORM:0886410/IV (b)/1> wherein R and R1 each designate a divalent aliphatic radical CnH2n, n being an integer from 2 to 18, the divalent cyclohexane residue or the divalent 2,5-endomethylene cyclohexane residue; and X and X1 both designate carboxyl radicals or each designate the nitrile or -COOR2 radical in which R2 is a C1-14 alkyl radical or a C6-9 monocyclic aryl hydrocarbyl radical, X and X1 being separated from the carbon atoms in the 3- and 9-positions by at least two carbon atoms.  They may be prepared by reacting pentaerythritol with at least one formyl compound OCH.RX in the proportion of at least 2 moles of formyl compound(s) per mol of pentaerythritol, at 50 DEG C. to 150 DEG C. in the presence of an acidic catalyst and an inert diluent while removing the water of reaction as it is formed, R and X being as defined above and X and the -CHO group being separated by at least 2 carbon atoms, di-ester products being hydrolysed if the di-acids are desired.  Catalysts specified are calcium chloride and hydrochloric, sulphuric and phosphoric acids. Suitable diluents are hydrocarbons, chlorinated hydrocarbons and ethers.  The products may be polymerised yielding linear condensation polymers; the diesters may be used as plasticisers for vinyl resins; and the dinitriles and nitrile-esters may be hydrogenated, for example, with hydrogen and Raney nickel at 100 DEG C.-125 DEG C. under 3-10 atmospheres-pressure in the presence of an inert diluent, yielding diamines and amino-esters useful as curing agents for epoxy resins (see Group IV (a)).  In examples there are prepared (1) 3,9-bis-(carbethoxypropyl)-2,4,8,10-tetraoxaspiro (5,5) hendecane; (3) 3,9-bis (carbethoxyethyl) - 2, 4, 8, 10 - tetraoxaspiro (5, 5) hendecane; (4) a mixture of 3,9-bis (3- and 4-carbothoxycyclohexyl - 2, 4, 8, 10 - tetraoxa - spiro (5,5) hexadecane isomers; (5) 3,9-carbethoxyethyl) (carb - 2 - ethylbutoxypropyl) - 2,4,8,10-tetraoxaspiro (5,5) hendecane; (6) a mixture of 3,9-bis-(3- and 4-carbethoxyendo-methylenecyclohexyl) - 2, 4, 8, 10 - tetraoxaspiro (5,5) henedecane isomers; (7) a mixture of 3 3,9-bis-(3- and 4-cyanocyclohexyl) - 2, 4, 8, 10 - tetra - oxaspir (5,5) hendecane isomers; (8) a mixture of 3,9-bis (carbethoxycyclohexyl)-, 3,9-bis (cyanocyclohexyl)- and mixed 3,9-(carbethoxycyclohexyl) (cyanocyclohexyl) - 2, 4, 8, 10 - tetraoxaspiro (5,5) hendecanes; (10) a mixture of 3,9-bis [8 - carbmethoxy (1 - n - nonyl) octyl] - and 3,9-bis [9-carbmethoxy (1-n-octyl) nonyl]-2, 4, 8, 10 - tetraoxaspiro (5, 5) hendecanes. In a number of cases the diesters are saponified and the resulting di-sodium salts acidified to give the free diacids; a resulting isomeric mixture of acids is partially resolved by fractional crystallisation.  Numerous other di-ester products are described and additional starting materials are listed.  Formyl nitriles utilisable as starting materials are prepared by reacting potassium cyanide with an appropriate bromacetal and subjecting the product to mild hydrolysis or by reacting acrylonitrile with an aldehyde such as isobutyraldehyde which gives 2,2-dimethyl-4-cyano-butyraldehyde.