Patent GB-981813-A (GB)
Title: Improvements in or relating to polyurea
IPC: C08L75/02
Filed: 1961-03-29
Abstract: A substituted urea is formed as an intermediate compound by reaction of a urea compound and a saturated aliphatic diprimary diamine with liberation of ammonia, in a continuous process for the preparation of polyureas (see Division C3). The term "urea compound" denotes urea, thiourea, substituted ureas, substituted thioureas, and diureas and dithioureas, e.g. alkylene diureas and alkylene dithioureas. The diamines include (a) polymethylene diamines having 4 to 12 carbon atoms; (b) hetero-membered diamines e.g. H2N-R1-O -R2-NH2, H2N-R1-S-R2-NH2 and others where R1 and R2 are polymethylene radicals; (c) saturated diamines of the formula <FORM:0981813/C2/1> where n is an integer from 2 to 19 and R stands for H or an alkyl radical, at least one R being alkyl. In example (1) urea, nonamethylene diamine, pelargonic acid amide (viscosity stabilizer) and water are continuously charged to a first reaction zone at 120 DEG  C., to give omega-amino-nonamethylene urea as product.  In other examples there are reacted (2) 1,8-diamino-2-ethyloctane, urea and palmitic acid; (3) 4,41-diamino-dibutyl ether, urea and pelargonic acid (viscosity stabilizer); (4) nonamethylene diamine carbonate, methylene bis-urea and palmitic acid; (5) urea, nonamethylene diamine, octamethylene diamine and palmitic acid amide; (6) 4,41-diamino-dibutyl sulphide, urea and pelargonic acid amide; (7) nonamethylene diamine, thiourea and water; (8) nonamethylene diamine, urea and palmitic acid amide; (9) nonamethylene diamine, methylene diurea, palmitic acid amide and water.  Specification 619,275 is referred to.  Reference has been directed by the Comptroller to Specification 864,889.ALSO:A process for manufacturing a spinnable polyurea polymer comprises in a first reaction zone forming a bimolecular condensation product with evolution of ammonia by condensing at least one starting diamine with at least one urea compound in substantially equimolecular proportions at a temperature not higher than 130 DEG C., reacting the said bimolecular condensation compound in the presence of a saturated aliphatic primary amine, the said amine being initially (a) a saturated aliphatic diprimary diamine or (b) an alkyl monoamine having at least three carbon atoms and a boiling-point less than that of the starting diamine or a mixture of the two amines (a) and (b), and thereafter being recycled amine as herein-after mentioned, in a second reaction zone having an inlet maintained at a temperature of about 110 DEG C. to about 130 DEG C. in a first heating area and an outlet maintained at a temperature of about 200 DEG  to about 260 DEG C. in a second heating area to form a polyurea prepolymer while evolving gaseous material including vaporous amine, withdrawing polyurea prepolymer from the second reaction zone outlet and thereafter reacting the polyurea prepolymer in a third reaction zone maintained at a temperature from about 200 DEG  to 260 DEG  C. and at a pressure of 1 to 50 mm. Hg to form the spinnable polyurea polymer while evolving gaseous material including vaporous amine, removing the gaseous amine and recycling a controlled amount of the amine contained therein through the second reaction zone, amine (a) and/or amine (b) being added periodically as required.  "Urea compound" means urea, thiourea, substituted ureas or thioureas, diureas and dithioureas and any compound which decomposes to provide such. "Saturated aliphatic diprimary diamine" is meant to include (a) polymethylene diamine; (b) diamines of the formulae H2N-R1-O-R2-NH2, H2N-R1-O-R3-O-R2-NH2, H2N-R1-S-R2NH2 H2N-R1-S-R3-S-R2-NH2 and H2N-R1-S-S-R2-NH2 wherein R1, R2 and R3 stand for a polymethylene radical having 2 to 8 carbon atoms; (c) compounds of the formula <FORM:0981813/C3/1> wherein n is an integer from 2 to 19, R stands for H or an alkyl radical having not more than 10 carbon atoms, at least one R being an alkyl radical. The diamines can be used in the form of their carbonates.  Reaction in the first zone can be carried out in the presence of such solvents as water, phenol, cresol or an alcohol. The amount of amine used in the second zone is preferably 2 to 20% by weight of the amount of initial saturated aliphatic primary diamine. A viscosity stabilizer is preferably added in the first or second zone.  Suitable are N-acyl-polymethylene diamine, an alkylmonoamide or a saturated aliphatic monocarboxylic acid with at least 3 and preferably 6 carbon atoms in the alkyl or acyl radicals.  In Example (1) urea, nonamethylene diamine and pelargonic acid amide (viscosity stabilizer) are reacted in a first zone at 120 DEG  C. to give omega-aminononamethylene urea. This is conducted to a second reaction zone comprising heated areas at 130 DEG  to 150 DEG  C. and 200 DEG to 230 DEG C., ammonia and water being formed in the first area and nonamethylene diamine and CO2 in the second heated area.  Product of the second reaction zone is passed to a third reaction zone kept at 250 DEG C. Nonamethylene diamine evolved in the third zone is recycled to the second zone.  In other examples the starting materials used are (2) 1,8-diamino-2-ethyloctane, urea, palmitic-acid (viscosity stabilizer), in water; (3) 4,41-diamino -dibutyl ether, urea and pelargonic acid; (4) nonamethylene carbonate, methylene bisurea and palmitic acid; (5) urea, nonamethylene diamine, octamethylene diamine and palmitic acid amide (reacted in m-cresol); (6) 4,41-diamino-dibutyl sulphide, urea and pelargonic acid amide (in water); (7) nonamethylene diamine and thiourea (in water); (8) nonamethylene diamine, urea, and palmitic acid amide (in water); (9) nonamethylene diamine, methylene diurea and palmitic acid amide in water.  Specification 619,275 is referred to.  Reference has been directed by the Comptroller to Specification 864,889.