THERMAL INSULATION PANEL Russian patent published in 2023 - IPC E04C2/24 E04B1/76 

FIELD: construction materials.

SUBSTANCE: heat-insulating panel contains outer and inner surface layers formed by co-extrusion from different compositions, the space between which is filled with a heat-insulating material. The outer surface layer contains a thermoplastic polymer having a melt flow strength of 4-12 g/10 min and a melting point of not more than 200°C, fibrous type wood particles with sizes from 1 to 2.5 mm pre-treated in an alkaline medium, isocyanate, process additive, and dye in the following ratio, wt.%: the specified thermoplastic polymer 30-35, wood particles ranging in size from 1 to 2.5 mm 54-56, isocyanate 7-10, process additive 2-3, dye 1-2. The inner surface layer contains a thermoplastic polymer having a melt flow strength of 4-12 g/10 min and a melting point of not more than 200°C, wood particles of fibrous type with sizes from 2.5 to 10 mm, in the following ratio, wt. %: the specified thermoplastic polymer 20-26, wood particles ranging in size from 2.5 to 10 mm 70-76, process additive 2-3, dye 1-2. The space between the surface layers is filled with polyol with a filler in the form of wood particles ranging in size from 10 to 15 mm, followed by the introduction of isocyanate into the mixture with the following ratio of components, wt.%: polyol 10-12.5, wood particles with sizes from 10 to 15 mm 75-80, isocyanate 10-12.5.

EFFECT: increased modulus of rupture, modulus of elasticity, ultimate compressive strength by an average of 1.3 times while maintaining a low coefficient of expansion in thickness during moisture absorption; expensive modifiers required to achieve the specifications are only used during formation of the outer surface layer reducing its cost, simpler composition of the inner surface layer, high strength parameters, high-quality interfacial layer between the matrix and the filler, significant improvement in strength and performance of the product.

2 cl, 1 dwg, 1 ex, 2 tbl