Patent GB-700617-A (GB)
Title: Production of mouldable or adhesive polyester compositions
IPC: C08G18/10
Filed: 1950-08-16
Abstract: Mouldable or adhesive compositions are made by mixing a tertiary amine free from reactive hydrogen with a linear or substantially linear polyester modified with an aliphatic or cycloaliphatic polyisocyanate in excess of the amount equivalent to the reactive groups of the polyester, and preserving the resulting mixture free from water until it is desired to solidify it by admitting water thereto.  Polyesters specified are preferably liquid at room temperature and are made from ethylene glycol, 1 : 2-propyleneglycol, thioglycol or quinite (preferably in excess) and adipic acid, phthalic acid or hydroxy acid, succinic, sebacic, thiodibutyric or maleic acid, which may be used instead of or mixed with adipic acid. Polyisocyanates specified are tetramethylene-, hexamethylene-, dodecamethylene-, cyclohexane-, dicyclohexylmethane-and thiodipropyldiisocyanates, a triisocyanate obtained from 1 mol. of hexanetriol and 3 mols. of hexamethylene diisocyanate and 1 : 2 : 2 - triisocyanatobutane. Tertiary amines specified are trialkylamines, N - N1 dimethylpiperazine, dimethylaminocyclohexane (hexahydrodimethylaniline), perhydroethylcarbazole, methyl- or butylpyrrolidine and homologues and quinoline and its homologues. Moulded articles may be made by solidifying the compositions in the desired shape.  Materials may be joined together by applying the composition to one or more surfaces thereof and solidifying the composition by the admission thereto of water.  The compositions find use in the bonding of driving belts, making multi - layer material from split leather, making plywood from thin veneers and in the doubling of fabrics to yield watertight fabrics, e.g. for automobile covers; as adhesives in making shoes and in shoe repairs; in making elastic threads, films, foils, tubes, elastic medical bandages and composite sheet fabrics; in making self-hardening masses by adding fillers containing water, e.g. sawdust, activated carbon, kieselguhr and alumina, to the compositions, the products obtained in this way being porous or cellular unless a carbon dioxide absorbing filler, such as soda time, is used; and in making artificial limbs, water-tight cable inlets and models.  In examples (1) hexahydrodimethylaniline is added to a liquid polyester from diethyleneglycol and adipic acid after reaction with hexamethylenediisocyanate and the resulting mass is spun into an aqueous bath containing piperazine.  The thread is wound on to a bobbin and hardened by atmospheric moisture; (2) a similarly prepared mass is dissolved in benzene and used for joining driving belts; (3) a hexamethylene diisocyanate modified polyester from adipic acid and diglycol is dissolved in benzene and mixed with hexahydrodimethylaniline. The resulting solution is distributed on the walls of a horizontally rotating tube and solidified by passing moist air through the tube, with formation of a rubber elastic tube which may be cut open to form a foil: (4) a hexamethylenediisocyanate modified polyester from phthalic acid and ethyleneglycol is mixed with methyl pyrrolidine and dissolved in benzene, the resulting solution being solidified as in (3) to form a foil suitable as a safety glass interlayer: (5) a hexamethylenediisocyanate modified polyester from succinic acid and diglycol is mixed with hexahydrodimethylaniline, the resulting solution being used as an adhesive for elastic medical bandages; (6) a 1 : 4 - cyclohexanediisocyanat modified adipic acid diglycol polyester is mixed with hexahydrodimethylaniline and diluted with benzene. Fabrics may be coated on one or both sides with this solution; (7) a hexamethylene diisocyanate modified diethyleneglycol - adipic acid polyester is mixed with hexahydrodimethylaniline and moist wood flour and the mixture is moulded.  The compositions may also be used for embedding an amputated limb in a quiver. Specifications 553,733 and 700,610 are referred to.ALSO:A benzene solution of an isocyanate-modified polyester (thermosetting) and a tertiary amine (see Group IV(a)) is introduced into a horizontally rotating tube and distributed on the walls thereof.  Solidification of the mixture is effected by passing humid air through the tube and a rubber elastic tube is obtained which may be cut open to yield a corresponding foil (see example 3).ALSO:A mixture of an isocyanate-modified polyester, a tertiary amine and moist wood flour (see Group IV(a)) is used for embedding an amputated limb in a quiver (see example 7).