| 摘要 |
1,235,376. Polyamides. IMPERIAL CHEMICAL INDUSTRIES Ltd. 1 April, 1969 [1 May, 1968], No. 20668/68. Heading C3R. During the production of a high M.W. fibre-forming polyamide or copolyamide (A), one or more substantially insoluble hydrogen phosphates (B) are added. " Substantially insoluble" is defined in terms of the proportion of P retained in a standard yarn after a standard immersion of the latter in water. The metal or other radical and the phosphate radical of (B) are present in substantially stoichiometric ratio. (B) may be added as such or be formed in situ; it may be added as a slurry or as a mix of stoichiometric amounts of hydrogen-phosphate forming salts (C). (B) may be added to the polymerization mixture, or e.g. by coating on polymer chips before melting and extrusion. There may be 10-1000 wt. parts (B) per million parts (A). In a continuous polymerization process, (B) may be added as a slurry to the entrant monomer solution or at any convenient point along the length of the polymerization zone; or salts (C) may similarly be added, together or separately, at convenient points. Exemplified substances (B) are CuHPO 4 , Cu- (H 2 PO 4 ) 2 , BaHPO 4 , Ba(H 2 PO 4 ) 2 , SrHPO 4 , MgHPO 4 and CoHPO 4 . Contrasting, less insoluble, substances are Na 2 HPO 4 , CaHPO 4 , and ZnHPO 4 . Salts (C) may be Na hydrogen phosphate and Mg or Ca acetate. When Cu hydrogen phosphates are used, a source of I, e.g. KI, is preferably present; these substances reduce yarn degradation on heating e.g. oxidative degradation or gel formation. (B) accelerates polymerization and increases M.W. of the polymer, and re-elevates the R.V. of a polymer to which excess basic material, e.g. H 2 N- (CH 2 ) 6 -NH 2 ) has been added to increase acid dyeability. Also present may be TiO 2 . The (co)polyamides (A) may be derived from or m - xylylenediamine; sebacic, adipic, 1,4- diphenyladipic, isophthalic, or terephthalic acids, or # - caprolactam or # - aminoundecanoic acid. The polymers may be prepared e.g. by heating hexamethylene diammonium adipate solutions in an autoclave, and may then be melt spun and drawn. Films may also be meltextruded. |
