INFLUENCE OF METHODS OF PREPARING POLYAMIDE-6 TO PROCESSES OF TREATMENT ON PROPERTIES OF FINISHED PRODUCT
Abstract
When preparing the polyamide-6 granulate for treatment proceses, its properties such as the content of low-molecular compounds (caprolactam and oligomers, LMC) and relative viscosity are normalized. Two alternative methods of preparing the polyamide-6 granulate for proceesing are used: 1) currently, the industry uses a method consisting of stages of aqueous extraction of low-molecular compounds from PA-6 granules, followed by drying of the latter and separation of LMC from extraction solutions by evaporation; 2) an alternative process is being developed, which consists in simultaneously carrying out the drying and demonomerization of polyamide-6 granulate. Through of these methods samples of granulate of polyamide-6 of 2 kinds were prepared: 1) equilibrium matted granulate of industrial production; 2) granules after solid-phase dopolyamination in a superheated steam environment. These samples were conversed by the re-melting method, which consists in melting the polyamide-6 granulate at T = 270 °C. The properties of these samples were determined before and after the conversion using the following methods: the content of low molecular weight compounds is determined by their extraction from granules. The content of caprolactam is determined by its sublimation from granules; the value of the relative viscosity is determined by viscometry. It is shown that during the process of conversion of the polyamide-6 granulate, the polymer acquires practically the same properties, regardless of the preparation method. Thus, it is proved that the process of combined drying-demonomerization is more advantageous in terms of energy and material costs than the process of extraction of low-molecular compounds from the polyamide-6 granulate.
Forcitation:
Barannikov M.V., Bazarov Yu.M. Influence of methods of preparing polyamide-6 to processes of treatment on properties of finished product. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 4-5. P. 72-75
References
Mizerovsky L.N., Bazarov Yu.M., Pavlov M.G. Prospects for perfecting production technology for polycaproamide used in production of textile and industrial fibres. Part I. Fibre Chem. 2003. V. 35. N 5. P. 329-335.
Mizerovsky L.N., Bazarov Yu.M., Pavlov M.G. Prospects for perfecting production technology for polycaproamide used in production of textile and industrial fibres. Part II. Fibre Chem. 2003. V. 35. N 6. P. 329-335.
Lipin A.A., Lipin A.G., Kirillov D.V. Prediction of rational mode-technological parameters of drying process of granulated polycaproamide. Vestn. Saratov. Gos. Tekh. Un-ta. 2011. V. 4. N 4. P. 106-109 (in Russian).
Bazarov Yu.M., Khromova T.L., Sadivskii S.Y., Koifman O.I. Composition and properties of caprolactam oligomers from extraction waters directed to regenerationю Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2016. V. 59. N 3. P. 65-68 (in Russian).
Lipin A.A. Simulation of the combined processes of drying and demonomerization of granulated polycaproamide. Vestn. Tambov. Gos. Tech. Un-ta. 2011. V. 7. N 2. P. 397-402 (in Russian).
Lipin A.A., Lipin A.G., Barannikov M.V. Kinetics of polyamide-6 demonomerization in inert gas flow. Sovr. Nauk. Tekhnnol. Reg. Pril. 2016. N 2. P. 91-98 (in Russian).
Lipin A.A. Mathematical model of the periodic drying-demonomerization process of polyamide-6. Mat. Met. Tekh. Tekhnhol. – MMTT. 2014. V. 68. N 9. P. 20-22 (in Russian).
Bazarov Yu.M., Barannikov M.V., Koifman O.I. Investigation of thermal processes occurring at heating solutions of caprolactam and its cyclic oligomers in amorphous areas of polyamide-6. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2019. V. 59. N 7. P. 47-50 (in Russian).
Lipin A.A., Lipin A.G., Kirillov D.V. Simulation of the process of drying and demonomerization of polyamide in a fluidized layer apparatus. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2012. V. 55. N 2. P. 58-88 (in Russian).
Lipin A.A., Lipin A.G. Mathematical modeling of the combined processes of drying and demonomerization of polyamide-6 in a counterflow apparatus. Usp. Khim. Khim. Tekhnol. 2011. V. 25. N 10 (126). P. 99-103 (in Russian).
Lipin A.A., Lipin A.G., Bazarov Yu.M., Barannikov M.V, Mizerovsky L.N. Calculation-experimental investigation of the combined process of drying and demonomerization of polyamide-6 in a periodic action apparatus. Teor. Osn. Khim. Tekhnol. 2017. V. 51. N 3. P. 315-322 (in Russian).
Bazarov Yu.M., Mizerovsky L.N. The principal improvement of the technology of polyamide-6 production, used in the fibres production. Encycl. Ing.-Khim. 2008. N 9. P. 20-31 (in Russian).
Kudryashov G.I., Nosov M.P., Volokhina A.V. Polyamide fibres. M.: Khimiya. 1976. 264 p. (in Russian).
Nikolaev A.F. Kryzhanovsly A.V., Burlov V.V. Technology of polymer materials. SPb.: Professiya. 2008. 544 p. (in Russian).
Platonov E.K., Stupa V.I., Stupa M.V. Modern ways of hardware design of processes of polymerization, extraction and drying of polycaproamide. Techniques for chemical fibers: Coll. of the International Scientific and Practical Conference. Chernigov. OJSC “Khimtekstilmash”. 2001. P. 170-190 (in Russian).
Sutyagin V.M., Lyapkov A.A. Physical-chemistry methods of polymers investigation. Tomsk: Izv. Tomsk. Polytekh. Un-ta. 2008. 130 p. (in Russian).
Barannikov M.V, Bazarov Yu.M. RF Patent N 2640657. 2018 (in Russian).
Isaeva V.I., Bazarov Yu.M., Mizerovsky L.N., Zakharov E.Yu., Kolobkov A.S. Low-temperature hydrolytic polymerization of caprolactam. Synthesis and processing of experimental batches of polymer into filament yarns. Fibre Chemistry. 2011. V. 3. N 1. P. 80-85.
Fishman K.E, Khruzin N.A. Production of capron silk. M.: Khimiya. 1976. 312 p. (in Russian).
Bazarov Yu.M., Mizerovsky L.N. Solid-phase synthesis of polyamide-6. Khim. Vol. 2006. N 4. P. 40-48 (in Russian).
