FIELD: chemical industry; methods and devices of molding of the thermoplastic polymeric materials.
SUBSTANCE: the invention is pertaining to the method and the device of molding of the thermoplastic polymeric material and its composition. The engineering solution of the invention concerns to polymers melt molding, mainly to the polymers melt molding by extrusion, and especially to the extrusion of polyolefins, in particular, polyethylene and may be used at manufacture of a polymeric profile, an insulating coating for an electric cable, a polymeric fiber, a polymeric pipe and a polymer film produced by a pipe ballooning. The technical result of the invention is an increase of the speed of the defect-free extrusion. In the process of the polymeric compounds melts molding onto the surface of the molding device being in contact with the melt of the polymeric compound superimpose a flexible coating. The method of the thermoplastic polymeric material molding provides for extrusion of the melt of the thermoplastic polymeric material with the additives of elastomers through the device for extrusion, deposition in the process of the extrusion of a flexible coating at least onto the sections of the being in contact with the melt surface adjoining to the outlet of the device and having the length of no less than 10 % of the clearance space for the polymeric material molding. Predominantly the flexible coating is superimposed by depositing the additives from the polymeric material melt on the indicated surface. In the capacity of the material for a flexible coating select the thermoplastic elastomers, which are more resilient as compared with a polymeric material melt, or the elastomers gaining resilience in the result of the vulcanization. In the latter case conduct a dynamic vulcanization of the layer of the elastomer in the process of the extrusion. The device for extrusion of a thermoplastic polymeric material with a flexible coating superimposed in the process of the thermoplastic polymeric material extrusion at least on the part of that surface of the device, which is intended to contact with the melt of the thermoplastic polymeric material, contains a catalyst for the corresponding reaction of vulcanization of the elastomers. The composition used for the thermoplastic polymeric material molding and for simultaneous deposition of the flexible coating on the device surface, which is intended to contact the melt containing polyolefins and the additives of elastomers is characterized by the fact, that in the capacity of the elastomers use the block copolymers of the rigid polymers (A) with the glass transition temperature exceeding the room temperature, but being below the temperature of the indicated polyolefins molding and the soft polymers (B) with the glass transition temperature below the room temperature. At that select the block copolymers with the structure of the linear block copolymer A(BA)n , where n>0, or (BA)m , where m>1, or the graft copolymer, when at least two side segments of a rigid polymer are grafted to the soft polymer at the following components ratio: the thermoplastic elastomers - 0.001-10 mass %; the thermoplastic polymeric material - the rest. The particular cases of realization of the offered engineering solution characterize the material for the coatings and the extrusion, the requirements for realization of the method and the engineering components of the device for the thermoplastic material molding.
EFFECT: the invention ensures an increased speed of the defect-free extrusion.
18 cl, 12 dwg, 2 tbl, 7 ex
