Improvements in or relating to the manufacture of polymeric materials

摘要

544,310. Polyamide condensation products. DU PONT DE NEMOURS & CO., E. I. Oct. 5, 1940, No. 14907. Convention date, Oct. 5, 1939. [Class 2 (iii)] Polyamides particularly of the high molecular weight fibre forming type described in Specifications 461,236, 461,237 and U.S.A. Specifications 2,071,250, and 2,130,948 are obtained by polymerizing an N-formyl derivative of a polymerizable monoaminomonocarboxylic acid, or by polymerizing an N formyl or an N : N1 diformyl derivative of a diamine and a dibasic carboxylic acid. The polymerization is carried out at temperatures of 200-300‹C., under increased or reduced pressure, and preferably in presence of an inert solvent or non-solvent e.g. white medicinal oil. There are specified : (1) N : N1 formyl derivatives of diaminestetramethyl, pentamethyl, 3-methylhexametbylene, octamethylene, triglycol, N : N1 dimethylhexamethylene-, xylylene-, 2 : 11 diaminododecane-, m-phenylene-, 2 : 4 toluene-, methylene-, ethylene-, and triethylenediamines ; (2) dicarboxylic acids-#-methyl-adipic, pimelic, malonic, glutaric, suberic, azelaic, p-phenylenediacetic, iso-phthalic, diglycollic, and thiodibutyric acids or their esters or anhydrides ; (3) formyl derivatives of monoaminomonocarboxylic acids-N-formyl-e-aminocaproic acid, N-formyl 10-amino capric acid OHC-NH-(CH 2 ) 6 -COOH, OHC-NH-(CH 2 ) 7 -COOH ; (4) solvents-phenol, m-cresol, o-hydroxydiphenyl ; (5) catalysts oxides, salts, metal halides, e.g. stannous chloride, zinc chloride ; magnesium sulphate, silica ; phosphoric, sulpburic, borophosphoric and p-toluenesulphonic acids ; (6) viscosity stabilizers-acetic acid, 2-ethylhexylamine, benzoic acid, or a small excess of the formyl derivative. In examples (1) a mixture of 8.60 parts of the N : N1-diformyl derivative of hexamethylenediamine (prepared by the heat treatment of hexamethylene-diammonium formate) and 7.30 parts adipic acid was heated in a nitrogen atmosphere for one hour at 255‹C. for one hour at 287‹C., and finally for an hour at the same temperature but under a pressure of 10 mm. absolute. A hard opaque solid was obtained having a m.p. 263‹C. and intrinsic viscosity 0.62 ; (2) 10 parts N-formyl-e-amonocaproic acid (prepared by refluxing e-aminocaproic acid with formic acid) was heated for 0.5 hours at 218‹C. for 0.5 hours at 255‹C., for 1 hour at 287‹C., and for 0.2 hours at 287‹C., and 10 mm. pressure.