Bulletin of
Vitebsk State
Technological
University

Abstract

In order to analyze the influence of the nature of the acid comonomer (АM) on the properties of polyacrylonitrile fibers, model fiber-forming tercopolymers (FFT) based on acrylonitrile (AN) and methyl acrylate (MA) were synthesized using such AM as 2-acrylamide-2-methylpropanesulfonic acid (AMPS) and itaconic acid (ItA) with their content in the initial reaction mixture varying from 0 to 2.0 % ((mass) of the comonomers mass). It is noted that the mass fraction of AM in the primary structure of poly[AN–co–MA–co–AMPS], synthesized in a hydrotropic solvent, is higher than its content in the initial reaction mixture, while the opposite trend is observed during the synthesis of poly[AN–co–MA–co–ItA].

Model samples of polyacrylonitrile fibers were formed on the basis of synthesized model poly[AN–co–MA–co–AM] and their properties were studied under identical conditions. The study of the structural and morphological properties showed that the replacement of AMPS with ItA in the FFT leads to a significant increase in the homogeneity of the structure of fibers obtained by the dimethylformamide method.

The amount of dye sorbed by fibers in the dry state is determined mainly by the content of acid groups in the FFT and is practically independent of the nature of the AM. Based on the totality of the obtained results, it was concluded that the optimal content of AMPS in the structure of the FFT intended for their processing into fibers of textile purposes can be in the range from 1.0 to 1.7 % (mass), and when using ItA – in the range from 0.7 to 1.5 % (mass). At the same time, the replacement of AMPS with ItA contributes to a greater intensity of dyeing of gel fibers with cationic dyes.

The influence of acidic comonomer on the properties of polyacrylonitrile fibers produced by the dimethylformamide method