SHEET OF COMPOSITE MATERIAL AND METHOD FOR PRODUCTION THEREOF Russian patent published in 2020 - IPC B29B7/00 B29C48/07 B29C48/305 

FIELD: chemistry.

SUBSTANCE: invention relates to composite material sheet production method. Technical result is achieved by a method of producing a sheet of composite material, which includes providing a thermoplastic material, in particular a polymer from a series of polyolefins, in the form of granules or powder. Provision of fibres of negligible origin, in particular glass fibres, in the form of groups or bundles of fibres having specified length, width and thickness. Mixing of thermoplastic material and fibres of negligible origin and separation of bundles of fibres during mixing. Feeding the obtained mixture into an extruder which extrudes the mixture through an extrusion head of an extruder and a sheet containing a three-dimensional fibrous structure whose fibres are interwoven and immersed in the thermoplastic material. At that, ratio of orientation distribution of fibres depending on direction of extrusion is set from ratio 1.2:1 to ratio 5.7:1 between fibre fraction oriented in direction of extrusion, and fraction of fibres oriented perpendicular to direction of extrusion. At that, bundles of fibres are obtained at the stage of formation from separate fibres, which adhere to each other, at that these separate fibres have length from 2 mm to 20 mm, and bundles have the shape of rods or cylinders with thickness from 0.5 mm to 2 mm. Adjustment of orientation of fibres relative to direction of extrusion is performed by changing, alternatively or in combination, temperatures of mixture of thermoplastic material and fibres of negligible origin and length of plate of extruder head from 30 cm to 100 cm.

EFFECT: technical result is prevention of fibrous filler separation from composite material and its dispersion in environment.

12 cl, 3 dwg