Structural and morphological features and properties of fibers, formed on the basis of poly[acrylonitrile-CO-methylacrylate-CO-itaconic acid] by the dimethylf ormamide method

The subject of the study was the structural and morphological features and mechanical properties of polyacrylonitrile fibers obtained by the dimethylformamide method. For this purpose, on the basis of an industrial tercopolymer of acrylonitrile, methyl acrylate, and itaconic acid, fibers were formed on a laboratory bench installation in water - dimethylformamide precipitation baths of various composition using spinnerets with round holes. The spinnability of a concentrated solution of a tercopolymer in dimethylformamide was evaluated. Microscopic examination of the resulted model samples was carried out and the influence of the composition and temperature of the precipitation bath on the uniformity of the structure and the shape of the cross section of the fibers was shown. The influence of the concentration and temperature of the precipitation bath on the deformability of the spinning solution jet and the value of the maximum multiplicity of the plasticization drawing of gel fibers in an aqueous medium at a temperature of 95.5 °С was noted. The physical and mechanical properties of model polyacrylonitrile fibers produced under various conditions were studied, and the influence of the composition and temperature of the precipitation bath on their specific breaking load, elongation at break, performance and shrinkage was determined. The principal possibility of the process of obtaining fibers by the dimethylformamide method based on a fiber - forming tercopolymer of acrylonitrile, methyl acrylate, and itaconic acid was shown.