Thermal stability of flexible polyurethane foams obtained from reactive phosphorus-containing polyols dispersed in polyethylene glycol

• Published in: Iranian polymer journal 2024-12, Vol.33 (12), p.1701-1711
• Main Authors: Kanemoto, Stanley Olivier, Onana, Pierre Christelle Mvondo, Cheumani, Arnaud Maxime Yona, Ndikontar, Maurice Kor, Lakshmi, Madurai Suguna
• Format: Article
• Language: English
• Subjects: Ceramics; Chemistry; Chemistry and Materials Science; Composites; Compressive properties; Compressive strength; Diisocyanates; Flame retardants; Flexibility; Glass; Natural Materials; Original Research; Phosphorus; Plastic foam; Polyethylene glycol; Polymer Sciences; Polyols; Polyurethane foam; Precursors; Specific gravity; Thermal degradation; Thermal stability; Toluene
• ISSN: 1026-1265; 1735-5265
• DOI: 10.1007/s13726-024-01351-4

Flame-retardant and flexibility-enhanced phosphorus-polyurethane foams (P-PUF)s were prepared from phosphorus–hydroxyl precursors and polyethylene glycol (PEG) as polyols. In the first step, three different precursors, such as tris-(5-hydroxypentyl) phosphate (P-Pen-OHs), tris-(4-hydroxybutyl) phosphate (P-But-OHs), and tris-(3-hydroxypropyl) phosphate (P-Pro-OHs) were synthesized and used as flame retardants. In the second step, the precursors were made to react with toluene-2,4-diisocyanate to modify the flexibility and flame retardancy properties of the P-PUF product. The P-PUFs were obtained by a one-shot process system and then analyzed for their thermal stability, flame retardancy, and compressive strength properties. Among all P-PUF samples, P-But-PUF showed the best compressive properties with a Young’s modulus value of 0.167 MPa. The compressive properties of P-PUF are found to be proportional to their relative density. These results show that the chemical structure of the phosphorus–hydroxyl precursor had a slight effect on the compressive properties as well as the porosity of the final materials. All the foams had T g values in the range of 58–70 ℃ and their thermal degradation in a nitrogen atmosphere started around 100 ℃. From the limiting oxygen index test, P-PUF samples are considered marginally stable materials with a slow-burning behavior that confirms the efficiency of reactive phosphorus-based flame retardants. Graphic abstract