| 摘要 |
A method of bonding fragmentary polymeric foam material, at least part of which is of polyurethane foam material, comprises mixing with the said material a reaction product of a polymer containing terminal hydroxyl groups and an organic compound having at least two -NCX radicals in the molecule, where X represents in the case of each radical either an oxygen atom or a sulphur atom, the said reaction product containing unreacted -NCX radicals, and curing the said reaction product. Curing can be effected adding water to the reaction product, or by using moist foam fragments or by applying steam to the mixture of dry material and reaction product. Foam materials from natural or synthetic rubber can be mixed with the polyurethane foam fragments. The fragments preferably have a maximum dimension of 0,5 to 1,5 cms. The ratio of fragmentary material to reaction product with NCX groups is preferably from 15:1 to 5:1. Suitable polymers are polyethers, polythioethers, polyesters and polyesteramides. As curing catalysts triethylamine, N-methyl or ethyl morpholine, and NNN1N1-tetramethyl 1,3-butane diamine are suitable. Flame retardants such as tris monochlorethyl or dichloropropyl phosphates can be incorporated in the products. In typical examples (1) fragments of polyether polyurethane foam wetted with water containing sodium salts of higher secondary alkyl sulphates are mixed with a prepolymer syrup (from polypropylene glycol and tolylene-2:4 and 2:6-diisocyanates) containing N-methylmorpholine and triethylamine. The mixture is moulded and cured under slight compression at 100 DEG C.; (5) a mixture of polyurethane foam fragments and natural rubber latex foam fragments is employed. Specification 898,271 also is referred to.ALSO:A method of bonding fragmentary polymeric foam material, at least part of which is of polyurethane foam material, comprises mixing with the said material a reaction product of a polymer p containing terminal hydroxyl groups and an organic compound having at least two -NCX radicals in the molecule, where X represents in the case of each radical either an oxygen atom or a sulphur atom, the said reaction product containing unreacted -NCX radicals, and curing the said reaction product. Curing can be effected by adding water to the reaction product or by using moist foam fragments or by applying steam to the mixture of dry material and reaction product. Foam materials from natural or synthetic rubber can be mixed with the polyurethane foam fragments. The fragments preferably have a maximum dimension of 0,5 to 1,5 cms. The ratio of fragmentary material to reaction product with NCX groups is preferably from 15:1 to 5:1. Suitable polymers are polyethers, polythioethers, polyesters and polyesteramides. As curing catalysts triethylamine, N-methyl or ethyl morpholine, and NNN1N1-tetramethyl 1, 3-butane diamine are suitable. Flame retardants such as tris-monochlorethyl or dichloropropyl phosphates can be incorporated in the products. In typical examples (1) fragments of polyether polyurethane foam wetted with water containing sodium salts of higher secondary alkyl sulphates are mixed with a prepolymer syrup (from polypropylene glycol and tolylene-2:4 and 2:6-diisocyanates) containing N-methylmorpholine and triethylamine. The mixture is moulded and cured under slight compression at 100 DEG C. (5) a mixture of polyurethane foam fragments and natural rubber latex foam fragments is employed. |
