The influence of the compatibilizers of an ethylene-vinyl acetate copolymer and sodium oleate on the processes of melting and crystallization and the supermolecular structure of polypropylene/copolyamide blends of composition 20/80, 40/60, and 50/50 wt.% has been investigated. It has been shown that a specific fiberization is clearly realized in the compatibilized blends even for compositions corresponding to the region of phase change. Two to three peaks of crystallization of polypropylene in the blends containing an ethylenevinyl acetate copolymer or sodium oleate have been revealed, which is attributed to the increase in the degree of dispersion of polypropylene as a result of the improvement in the specific fiberization and to the growth in the fraction of polypropylene in the interphase transition layer.It is well known [1] that polymer blends are being used in a modern, simple, and efficient method of modifying them and obtaining products with completely new properties. Thus, for example, processing of polymer blends opens up a completely new avenue for production of ultrafine synthetic fibers (microfibers). We are dealing with the so-called phenomenon of specific fiberization [2], where one (fiberizing) component forms numerous microfibers strictly oriented in the direction of extrusion in the mass of another (matrix) component in the case of flow of a molten blend. The morphology of a polymer blend is determined not only by the microrheological processes (deformation of droplets to liquid jets, disintegration of the latter into droplets, and migration on the radius of the extruder-die orifice) at the stage of processing but also to a large extent by the capacity of the blended polymers for crystallization and by the conditions under which it occurs. Realization of specific fiberization substantially depends on the degree of compatibility of the components of the blend and the possibility of forming a transition layer transferring the deforming force from the matrix polymer to the fiberizing polymer. Commercially produced polymers are thermodynamically incompatible, as a rule. Therefore, in processing their blends, one adds special substances improving their compatibility; they are called compatibilizers [3]. Physicochemical processes in compatibilized polymer blends were investigated in [4,5] in detail, but no consideration was given to phase transitions.This work seeks to study the processes of melting and crystallization in ternary compatibilized polymer blends.Objects and Methods of Investigation. Blends of polypropylene (PP) and copolyamide (CPA) with a ratio of the components of 20/80, 40/60, and 50/50 were used as the objects of investigation. Copolyamide represented a caprolactam-AH (adipic acid and hexamethylene diamine) salt copolymer of composition 50/50. The characteristics of the starting polymers have been given in [4,5]. As the compatibilizers we used an ethylene-vinyl acetate copolymer (EVAC) and sodium oleate. We added EVAC in an amount of 5, 10, 20, and 25% of the PP mass. The amount of ...

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Solid nanosize Aerosil additives almost do not alter the properties of melts of PP/CPA blends. Melts of threecomponent blends are strengthened in a longitudinal velocity gradient field, manifested by a sharp increase in the maximum possible spinneret drawing. Nanosize Aerosil additives do not prevent realization of specific fibre formation in flow of melts of PP/CPA blends. As a result of stabilization of the liquid jets of PP in a CPA matrix, thinner (up to 0.30-0.15 μm) microfibres are formed with low dispersion of the distribution by diameters. This increases the specific surface area by 3-4 times. Nanofilled PP microfibres and new filter materials that combine high output and efficiency (99.999% with respect to 0.3 μm particles) were made for the first time. Aerosil additives act as crystallization centers during spinning of PP microfibres, which prevents the liquid jets from breaking down into drops. Incorporation of highly disperse Aerosils can be a method of regulating crosslinking of the polymer in the disperse phase in the matrix polymer.In the last decade, the nanostructural state of materials has been of great interest to scientists, and the research in this direction has become an important world trend. When the nanostructural state is attained, the basic functional characteristics of the materials change sharply and unique properties appear [1]. Data on the nanostate in polymers are usually limited to patent information. Polymeric nanofibres obtained primarily by electrospinning acquire unique properties: color change, ultrasound generation, reaction to specific signals, change in the pH of the medium, temperature, concentration of solutions, etc. However, solving the problems related to technical difficulties and the complexity of production of nanomaterials and the high cost of the final product remain pressing.Manufacturing nanofibres from melts of polymer blends implies reducing the diameter of the microfibres to nanosizes. One way of doing this is to add compatibilizers [2, 3], whose mechanism of action consists of decreasing the interfacial tension. By affecting interfacial events, structure formation processes can be regulated toward reducing the diameter of the microfibres. Research is also developing intensively in the polymeric nanocomposite sector, which is producing materials with unique properties [5].We investigated production of polypropylene microfibres containing a filler in the nanostate by processing melts of polymer blends. There is no published information on this topic and this research is being done for the first time.Polypropylene/copolyamide (PP/CPA) blends in the ratio of 30/70 wt. % were investigated. Industrial samples of PP and CPA were used: brand 2103016 polypropylene manufactured by Lisichansk chemical plant, brand PA-6/66-3 copolyamide manufactured by Ural Plastik IA (alcohol-soluble copolymer of 50% caprolactam and 50% hexamethylene adipate) were investigated.