INFLUENCE OF THE DEGREE OF COMPATIBILITY OF POLYMERS ON THE RHEOLOGICAL PROPERTIES OF A MIXTURE MELT AND THE PROCESSES OF STRUCTURE FORMATIONM. V. Tsebrenko, V. G. Rezanova, and I. A. Tsebrenko UDC 541.64:532.135 A study has been made of the rheological properties of the melts and the processes of structure formation of polypropylene/copolyamide mixtures containing additions of individual compatibilizers and their mixtures: ethylene copolymer with vinyl acetate, sodium oleate, and siloxane liquids. The compatibilizing effect manifests itself as a decrease in the interfacial tension, which improves the fiberization of polypropylene in the copolyamide matrix. It is shown that the introduction of these additives makes it possible to realize the phenomenon of specific fiberization in the region of a phase change in the polypropylene/ copolyamide mixtures of composition 40/60, 50/50, and 60/40. The introduction of binary mixtures of compatibilizers is more efficient than the introduction of individual substances. The melts of such mixtures are characterized by a higher elasticity and a pronounced capacity for being longitudinally deformed. Kiev National University of Technologies and Design, Kiev, Ukraine; email:vlasenko@ekma.Kiev.ua. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 76, No. 3, pp. 68-75, May-June, 2003. Original article submitted December 2, 2002.