Modification of Polyamide by Direct Capping Reaction of the Terminal Amino Groups with Triazine Derivatives Containing Sulfonate Moieties

Abstract

To improve the functional properties of Nylon-6, several s-triazine compounds with phenoxy and sulfonate substituents were synthesized and reacted with Nylon-6 in melt state. Especially, sodium 4(4, 6-diphenoxy-1, 3, 5-triazin-2-ylamino) benzenesulfonate (1a) consisting of a s-ulfanilic acid unit was found to react selectively with the terminal amino groups without decreasing its original solution viscosity, when the molar ratio of la relative to the terminal amino groups of Nylon-6 was 1-2. The reaction was confirmed by the decrease of the terminal amino groups. Sodium 4 ( 4, 6-diphen oxy-1, 3, 5-triazin-2-ylamino) ethanesulfonate containing taurine unit was also effective for the capping reaction, although the solution viscosity of Nylon-6 was much decreased probably due to the amide exchange reaction with taurine moiety. The reaction product of Nylon-6 and 1a was spun into filaments, which showed an decreased dyability to an acidic dye but an improved dyability to a basic dye compared with those of the original Nylon-6. When the filament was treated by the aqueous solution of poly(oxyethylene) with amino terminal groups, the water absorption was increaseed to 11%.