POLYMERIC SHEETS, METHODS FOR MAKING AND USING SAME, AND ARTICLES COMPRISING POLYMERIC SHEETS Russian patent published in 2018 - IPC C08J9/00 C08J9/08 B29C44/00 B29C44/24 C08J9/36 B29D7/01 B32B27/06 C08J5/18 

FIELD: chemistry.

SUBSTANCE: invention relates to polymeric sheets comprising a foamed inner layer or a foamed protective layer(s). Polymeric sheet comprises a foamed layer comprising a polymeric material, the polymeric material having Tg greater than or equal to 100°C, and wherein the foamed layer is a foamed layer with closed-type cells, which is foamed with a chemical foaming agent comprising at least one of monosodium citrate, citric acid, 5-phenyl-3,6-dihydro-2H-1,3,4-oxadiazin-2-one, 5-phenyl-1H-tetrazole and combinations comprising at least one of the above; the sheet is characterised by a reduction in weight by 10-60% in comparison with a monolithic sheet of the same shape and size, obtained from the same polymeric material; and wherein the sheet having a thickness of 1.0 mm satisfies at least one of the following heat release requirements: 1) is characterised by a two-minute total heat release rate less than or equal to 65 kilowatt-minutes per square metre and a peak heat release rate of less than 65 kilowatts per square metre in accordance with Part IV, OSU Heat Release of FAR/JAR 25.853, Amendment 25-116; 2) is characterised by a maximum averaged rate of heat emission (MARHE) of less than or equal to 90 kW/m² with 50 kW/m² irradiance level test condition according to ISO 5660-1; wherein the sheet of thickness 1.0 mm is characterised by a smoke density of less than or equal to 200 after four minutes of burning according to ASTM E662-06; and the sheet is thermoformable.

EFFECT: disclosed are lightweight polymeric sheets that can be thermoformed and that do not require additional lamination of other sheets/films to produce a sheet with a functional purpose of, for example, reducing overall weight, improved fire safety, and/or have an aesthetic surface.

40 cl, 11 dwg, 17 tbl