TY JOUR TI THERMAL INSULATION COMPOSITE MATERIAL BASED ON SODIUM SILICATE AND POLYURETHANE FOAM MATRIX KW silicate component KW sodium metasilicate KW pore structure KW rigid polyurethane foam KW flammability KW density KW compressive strength KW water absorption KW thermal conductivity JO Technique and technology of silicates AU Lipka, P.A. AU Borisenkov, N.S. AU Mironova, K.A. AU Chesnokova, D.S. AU Bruyako, M.G. PY 2026 IS 33 PB Individual Entrepreneur Svetlana Vasilievna Samchenko