Abstract
Fibres now on the market containing <85%, but not <35%, acrylonitrile, are called "modacrylic" fibres. Modaerylic fibres usually have much greater flame resistance than acrylic fibre, due principally to the content of vinyl chloride or vinylidene chloride in the polymer structure. When acrylonitrile is copolymerized with 20-40% vinyl chloride, the flame resistance is greatly enhanced, but the sticking temperature is below 150 °C. Since the acrylonitrile and vinylidene chloride copolymerization can be carried out at atmospheric pressure, the production of these copolymers is extremely advantageous from the industrial viewpoint, due to the low cost of apparatus and high production efficiency. Furthermore, vinylidene chloride copolymer contains a larger limiting oxygen index (LOI) than vinyl chloride copolymer [1]. Therefore, the acrylonitrile and vinylidene chloride copolymer was used in this study. Coover and Dickey [2] discovered a technique for block-copolymerizing acrylonitrile and vinylidene chloride. By this method, vinylidene chloride is first emulsion-polymerized, and acrylonitrile is then added to the so-called "live polymer" at the same time as more catalyst, and the polymerization is continued. The redox catalysts sodium bisulphite, ammonium persulphate and ferrous sulphate are very good catalysts for the suspension copolymerization of acrylonitrile and vinylidene chloride [3]. During wet-spinning with N,N-dimethylacetamide (DMAC) solvent the cross-section shape and structure for modacrylic fibre can be controlled by spinning variables such as the temperature and concentration in the coagulation bath [4], and the modacrylic fibre spun with DMAC solvent exhibits a higher LO! value and higher water adsorption than commercial modacrylic fibres [5]. The inflammability and mechanical properties of modacrylic fibre depend largely on the chlorine content of the modacrylic copolymer, and the correct type of spinneret for obtaining an excellent property can also be changed with the amount of the chlorine in the polymer. Therefore, in this study it was addressed in detail.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
