FIELD: chemistry.
SUBSTANCE: claimed invention relates to thermoplastic elastomer composition and method of its obtaining. Described thermoplastic elastomer composition is based on mixture of styrene block-copolymer with diene copolymers for insulation of flexible cables, for manufacturing sealants for windows and doors, gaskets, roofing materials, automobile components, for manufacturing consumer goods, which includes elastic rubber phase, thermoplastic polyolefin phase, plasticiser, filling agent and stabilising agent; as rubber phase taken is block-copolymer of styrene with diene copolymers, which has tree-block structure, namely two rigid crystalline polysterene blocks, connected to each other by means of flexible blocks of copolymers of diene monomers, with application of copolymers with content of polystyrene units not less than 25 wt %, namely as described block-copolymers selected are styrene/butylenes-styrene block-copolymers, or styrene-ethylene/propylene-styrene block-copolymer, or styrene-(ethylene-ethylene/propylene)-styrene block-copolymer, or their combinations with molecular weight from 300000 to 600000 g/mol; as thermoplastic polyolefin phase taken is combination of crystalline polymer, selected from the group: polyolefins, namely low-pressure or high-pressure polyethylene (LPPE or HPPE), polypropylene (PP), homopolymer, statistic or random copolymers, with addition of ethylene-vinylacetate copolymer of (EVAC) with content of vinylacetate groups not less than 10%; as plasticiser selected is mineral paraffin oil,; filling agent is selected from calcium carbonate, talc, kaolin, carbon soot, as well as their combinations; as stabilising agents selected are amine or phenol antioxidants, with said components being taken in the following ratio: elastic phase of styrene block-copolymer from 15 to 80 wt %, thermoplastic polyolefin phase from 0.1 to 60 wt %, mineral paraffin oil from 0.1 to 90 wt %, filling agent from 0.1 to 80 wt %, thermal stabiliser from 0.1 to 5 wt %. Method of preparing said thermoplastic elastomer composition is also described, which includes mixing components at higher temperature in Brabender mixer, characterised by the fact that first plasticiser is divided into two portions, first of which constitutes from 20 to 50% of total amount of plasticiser, after that, mixture of polymers and stabilising agent are loaded into chamber of twin-screw mixer with co-rotation of screws of Brabender type and mixing is started at temperature from 180 to 200°C and rate of rotor rotation from 90 to 110 rev/min for 5-7 minutes, after melting and homogenisation of mixture first portion of plasticiser is added and mixing is carried out for another 5-7 minutes under the same conditions, after which, filling agent is introduced, and with introduction of second portion of plasticiser after its distribution in melt, with total time of mixing constituting from 20 to 25 minutes.
EFFECT: increase of deformation and strength properties of composition.
2 cl, 1 tbl
