Patent GB-484697-A (GB)
Title: Rubber-like materials and method of producing same
IPC: C08F36/00
Filed: 1936-08-05
Abstract: Synthetic resins are produced by reacting a poly-glycol having at least eight atoms in the chain between the hydroxyl groups with a polybasic acid or anhydride stable at resinification temperatures and containing at least three esterifiable carboxyl groups, said acid being derived by condensation of a "diene material" with maleic or fumaric acid or maleic anhydride, the reaction being carried out at 140-250 DEG  C. until an infusible, substantially insoluble, rubber-like product is produced.  "Diene material" is defined as terpenes, terpene acids, eleostearic acids, their homologues and esters.  There may also be present not more than 60 per cent of dibasic acids, e.g. phthalic, succinic, adipic, sebacic, D -4 : tetrahydrophthalic acids and those obtained by condensing maleic anhydride with l-a -phellandrene, cineol, pinene, limonene, dipentene, terpinolene, terpinene. Materials specified are; "diene materials"-limonene, dipentene, a -phellandrene, terpinolene, a - and b -pinene, turpentine, abietic acid, rosin, b -eleostearic acid, b -eleostearin, and tung oil; poly glycols-tri- and tetra-ethylene glycols, poly-methylene, polypropylene, poly-butylene, or poly-amylene glycols.  The reaction may be interrupted at the A stage by the addition of organic solvents, e.g. acetone, ethylene glycol mono-ethyl ether, benzene, toluene, xylene, ethyl lactate, or mixtures thereof, to product coating or impregnating compositions. Those products approaching the C stage may be moulded and/or cured, preferably in an inert atmosphere, e.g. of nitrogen or carbon dioxide, at 140-250 DEG  C.  The resins may be modified by admixture or reaction with drying or non-drying oils and their derivatives, e.g. mono- or di-glycerides, free fatty acids, polymerized, blown, or vulcanized oils; phenol- or urea-aldehyde resins, vinyl or polyvinyl esters, rosin, ester gum, fossil resins and their esters: or by admixture with plasticizers, e.g. monohydric alcohols and esters such as alkyl phthalates, alkyl or aryl phosphates; natural or synthetic rubber.  The resins may be used in the production of moulded brake blocks, laminated or impregnated brake linings and clutch facings, oil-proof seals and gaskets, floor coverings, cable insulation, varnished cambric, oil-cloth, oil-resistant tubing, printing rolls, flexible abrasive wheels, abrasive paper and cloth, paints and enamels.  In examples: d-limonene is refluxed with maleic anhydride, the product vacuum-distilled, and the residual tetrabasic acids condensed with tetra-ethylene glycol; l-a -phellandrene is heated with maleic anhydride, the product fractionally crystallized from warm benzene, the mother liquor evaporated and vacuum-distilled, and the tetrabasic acids condensed with tetra-ethylene glycol; b -eleostearic acid or b -eleostearin is heated with maleic anhydride and the product condensed with triethylene glycol; tung oil is heated with fumaric acid and the product condensed with triethylene glycol; dipentene is heated with maleic anhydride to produce a product containing about 40 per cent tetrabasic and 60 per cent dibasic acids, which product is condensed with triethylene glycol.  The products of the examples are mixed with asbestos, rolled to thin sheets, and cured at 150 DEG  C. in carbon dioxide.  According to the Specification as open to inspection under Sect. 91, the resins are prepared from glycols having at least eight atoms in the chain between the hydroxyl groups and heatstable acids containing three or more carboxyl groups in general; other polyhydric alcohols, e.g. glycerol, polyglycerols, ethylene or propylene glycols, may be present.  Reference is also made to compositions with polymerized chlorbutadiene.  This subject-matter does not appear in the Specification as accepted.