Polyurethane foams with purine ring and boron

The method of synthesis of oligoetherols with purine ring and boron was presented based on reaction of hydroxyethyl derivative of uric acid with boric acid and alkylene carbonates. Their physical properties and structure were established. The obtained oligoetherols were suitable reactants to obtain polyurethane foams. The foams were further obtained and characterized by measuring their apparent density, water uptake, linear dimension changes, and heat conductance. It has been found that polyurethane foams have enhanced thermal resistance, diminished flammability, and better mechanical properties than polyurethane foams obtained from oligoetherols synthesized from uric acid and alkylene carbonates. The flaming rate of polyurethane foams with purine ring and boron was lower in comparison with foams with purine ring only (6.2–6.5 mm/s) and in case of the best compositions, i.e. those with high thermal resistance and appropriate compression strength it was as low as 0.86–1.25 mm/s.