FIELD: packaging.
SUBSTANCE: group of inventions relates to expandable polymer compositions used for manufacture of packaging. The expandable polymer composition for manufacture of packaging comprises: a) from 70 to 90 wt.% vinyl aromatic polymer and/or vinyl aromatic copolymer per (a)+(b), b) from 10 to 30 wt.% ethylene and vinyl acetate (EVA) copolymer containing from 10 wt.% to 30 wt.% vinyl acetate per (a) + (b), c) from 3 to 10 wt. parts of the expanding agent per 100 wt. parts of the sum of the amounts of component (a) and component (b), wherein such copolymer (b) is distributed in the polymer (a) in form of particles with an average volumetric diameter from 1 nm to 2000 nm, provided that the composition does not contain styrene-butadiene or styrene-isoprene block copolymers, hydrogenated or non-hydrogenated, thermoplastic polyurethane, grafted polystyrene-butadiene polymer or core-skin styrene polymer. The weight-average molecular weight of the vinyl aromatic polymer component (a) is between 130 and 250 kDa, wherein said copolymer (b) is in a state of chemical or physical adhesion with the vinyl aromatic polymer and/or copolymer. Also described are methods for mass producing expandable polymer compositions for manufacture of packaging, expanded balls, and packaging containing the balls or the expandable compositions.
EFFECT: technical result is a provided composition used for manufacture of a package exhibiting reduced abrasive ability relative to the surfaces of the packaged objects, improved impact resistance, reduced modulus of elasticity, low permeability of the foaming gas, wherein the foamed particles comprised in the package have good adhesion with each other and do not separate during use.
13 cl, 4 tbl, 6 ex, 1 dwg
