Preparation and characterization of rigid polyurethane foams with carbamide and borate groups

Abstract

The results of research on the application of hydroxyethyl urea derivatives modified with boron as polyol components to produce foamed polyurethane materials are presented. The obtained rigid polyurethane foams are characterized by good heat-insulating parameters and decreased flammability. The decrease in flammability of the foams follows from the presence of boron and increased nitrogen content, resulting from the use of polyol with urea groups. The incorporation of boron into the foam structure also results in a substantial increase in the compression strength, compared to classic foams and to non-boron-modified ones. The self-extinguishing foams of high mechanical strength can find application as heat-insulating construction elements for the building industry.

Thermal Conductivity and Flammability of Ulexite Filled Rigid Polyurethane Materials

“…Also, higher thermal stability and fire resistance was obtained. Zarzyka [12] investigated the application of boron-modified hydroxyethyl urea derivatives as polyol components to produce (825) foamed polyurethane materials. This results showed better heat insulation properties and decreased flammability.…”

Thermogravimetric and qualitative analysis of thermal decomposition characteristics of polyurethane foams based on polyols with carbamide or oxamide and borate groups

“…In turn, the borate groups were incorporated to initiate a synergistic action of nitrogen and boron resulting in a greater reduction of foam flammability. The impact of the conducted modifications, in the context of flammability reduction, has been discussed previously . In this paper, issues concerning thermal stability of the foams and the products of their decomposition are mainly discussed.…”

“…The composition of the foams is given in Table . The detailed characteristics of the foams are described elsewhere . However, it should be mentioned that the described polyols were foamed with the use of polymeric MDI as an isocyanate component, water as a chemical blowing agent and TEA as a catalyst.…”

“…The polyols were obtained in a reaction of: N , N ′‐bis(2‐hydroxyethyl)urea with 6‐, 12‐ and 18‐molar excess of ethylene carbonate – PU1, PU2, PU3, respectively; the product of the reaction of N , N ′‐bis(2‐hydroxyethyl)urea with 2‐molar excess of boric acid in the presence of solvent and next with 6‐, 12‐ and 18‐molar excess of ethylene carbonate – PUB1A, PUB2A, PUB3A, respectively; the product of the reaction of N , N ′‐bis(2‐hydroxyethyl)urea with 2‐molar excess of boric acid without the presence of solvent and next with 6‐, 12‐ and 18‐molar excess of ethylene carbonate – PUB1B, PUB2B, PUB3B, respectively; N , N ′‐bis(2‐hydroxyethyl)oxamide with 6‐ and 12‐molar excess of ethylene carbonate – PO1, PO2, respectively; the product of the reaction of N , N ′‐bis(2‐hydroxyethyl)oxamide with 2‐molar excess of boric acid in the presence of solvent and next with 6‐, 12‐ and 18‐molar excess of ethylene carbonate – POB1, POB2, POB3, respectively.…”

“…Polyurethane foams were obtained according to the procedure described in detail elsewhere . Polyurethane foams were prepared using a one‐step method.…”