Preparing cationic dyeable polyamide 6 filaments by combining the masterbatch technique with melt copolymerization

Abstract

Cationic dyeable polyamide 6 (CD-PA6) fiber, as a novel functional polyamide 6 (PA6) fiber, conforms to people's requirements for fashion clothing. However, due to the limitation of the hetero-end groups after caprolactam hydrolysis, it is difficult to introduce comonomers into the PA6 molecular chain to prepare PA6-based polymers with a certain molecular weight and maintain the original physical properties and spinnability. In this paper, through molecular design of PA6 segments, 5-sulfoisophthalic acid monosodium salt (5-SSIPA) was introduced into PA6 by copolymerization, and a CD-PA6 masterbatch with an addition amount of 10 wt% was prepared. CD-PA6 were prepared by blending with pure PA6 with masterbatch technology. The melt-spinning method was used to prepare CD-PA6 filaments, and they were woven into fabrics. The results show that the CD-PA6 masterbatch and PA6 have good blending compatibility. CD-PA6 filaments and fabrics maintain the excellent physical properties of PA6. When the addition amount of 5-SSIPA is 3%, the dye uptake rate of the cationic pigment exceeds 90%, and it has color affinity and excellent color fastness.

Preparation of a Novel Branched Polyamide 6 (PA6) via Co-Polymerization of ε-Caprolactam and α-Amino-ε-Caprolactam

“…Currently, industrial PA6 is mostly prepared by the hydrolytic ring-opening polymerization of ε-caprolactam (CPL) at high temperature, which has the advantages of relatively mild reaction conditions, easy scale-up production, and narrow molecular weight distribution. However, due to the influence of the hydrolytic ring-opening chemical equilibrium, the molecular weight of industrial PA6 is not high [ 1 , 4 ]. Linear PA6 with low molecular weight has an insufficient melt strength, which limits its application in thermal forming, injection molding, foaming, and other fields dominated by stretching flow [ 5 ].…”

Sustainable Production of Polyamide 6 Fibers: Direct Melt Spinning and Efficient Reuse of Residual Oligomers during Polymerization

“…Polyamide 6 (PA6) fibers are currently the second largest synthetic fibers in the world due to their high strength, good fatigue resistance, good weather resistance, and chemical stability. They have been widely used in textiles and industrial fibers. − However, the current production of PA6 fibers still uses chip spinning, and direct spinning of PA6 melt has not yet been achieved.…”

“…It allows the establishment of a new reflective equilibrium at low temperatures, thus reducing the content of oligomers. , However, it is difficult to maintain the homogeneity and stability of the melt. In our previous work, ,, a series of PA6-based polyamides were prepared by molecular design based on the hydrolytic polymerization of CPL. Although the oligomer content was effectively controlled, the cyclic dimer content could not be reduced, and melt spinning was only achieved by blending with pure PA6.…”