Abstract: A process for the production of a polyamide stabilizer concentrate in which the concentrate consists of at least two interactive stabilizer components with defined particle sizes and, optionally, micro-dispersed silicic acid, as well as a wax bonding agent with a solidification temperature t.sub.A between 65.degree. and 120.degree. C., in which a homogeneous mixture of these ingredients is compacted into tablets when subjected to a compression force p that is sufficient to heat the mixture to a temperature of at least 40.degree. C. and equal to t.sub.A minus 10.degree. to 50.degree. C.

Abstract: Process for synthesis of spinnable polyamide from .alpha., .omega.-alkyldinitriles and .alpha., .omega.-alkyldiamines and excess water, where a) the aqueous solution of the dinitrile is mixed with a catalytic amount of at least one oxygen-containing acid of phosphorus and/or a water-soluble salt of calcium, zinc, cadmium or manganese in the absence of the diamine, and the pH of this solution is adjusted to an initial value in the range of 2.0 to 4.0 before hydrolysis by adding a saturated aliphatic or aromatic dicarboxylic acid and the dinitrile is and the amide-containing precursors derived therefrom are hydrolyzed to dicarboxylic acid at an elevated temperature under autogenous pressure, whereby the hydrolysis is controlled by conductometric determination of the hydrolysate, and b) at least an equimolar amount of diamine is added to the solution from step a) and the mixture is subjected to polycondensation to form polyamide [nylon].

Abstract: Discontinuous catalytic process for the production of polyamide-6,6 by heating an aqueous AH-salt solution containing HPO.sub.3.sup.2- -ions, precondensing the solution with evaporation of water at 7 to 10 bar pressure and polycondensing in the melt phase, whereby the heating rate above 175.degree. C. of the AH-salt solution is at least in the range of 0.5.degree. to 3.0.degree. C./minute, the rate of evaporation of water is at least 2%/minute (based on the quantity of water in the AH salt solution). The total residence time for a polymer having a relative viscosity of 2.2 to 3.0 for heating from 175.degree. C., precondensation and melt phase polycondensation, is not more than 90 minutes.

Abstract: Discontinuous process for the production of polyamide-6,6 by heating an aqueous AH-salt solution, precondensing the solution with evaporation of water at 6 to 9 bar pressure and polycondensing in the melt phase, whereby the heating rate above 175.degree. C. of the AH-salt solution is at least 1.degree. C./minute, the rate of evaporation of water is at least 2%/minute (based on the quantity of water in the AH salt solution), the retention time for heating from 175.degree. C. and precondensation is not more than 75 minutes and the total retention time including polycondensation is not more than 120 minutes.