An Investigation on Synergism of an Intumescent Flame Retardant Based on Silica and Alumina

Abstract

Silicon-based materials appear potentially to be attractive flame-retardants because of the protective coatings formed in fire, which decreases the rate of heat release. But few reports were presented about inorganic materials, such as SiO₂, Al₂O₃, used as additive flame-retardants. In this paper the degradation process of the intumescent system, polypropylene (PP)/Ammonium Polyphosphate (APP)-Pentaerythritol (PER), with and without SiO₂, Al₂O₃ or blend of SiO₂ and Al₂O₃ was investigated by means of cone calorimetry, TGA, LOIs measured at ambient and elevated temperature (represented by a _t and TI, respectively). For PP/APP-PER system with the blend of SiO₂ and Al₂O₃ a maximal synergy was observed at the highest LOI of 35.5%, 17 units higher than the virgin PP. Its excellent flame-retardance was also evidenced by the highest residue char measured from TGA and parameters (MRL, PK-HRR, etc.) from Cone calorimetry.

Get full access to this article

View all access options for this article.

References

1. Camino, G. and Iuda, M.P. (1998). Mechanistic Study on Intumescence, In: Fire Retardancy of Polymers, The Use of Intumescence, pp. 48-63.

2. Camino, G., Costa, L. and Trossarelli, L. (1984). Polymer Degradation and Stability, 53(6): 243 .

3. Camino, G., Costa, L. and Trossarelli, L. (1984). Polymer Degradation and Stability, 54(7): 25-31 .

4. Camino, G., Costa, L. and Trossarelli, L. (1984). Polymer Preparation, 25(1): 90 .

5. Camino, G., Martinasso, G. and Costa, L. (1990). Polymer Degradation and Stability, 27: 285-296 .

6. Bourbigot, S. and Le Bras, M. (1996). Zeolites: New Synergistic Agents for Intumescent Fire Retardant Thermoplastic Formulations-Criteria for the Choice of the Zeolite , Fire and Materials, 20: 145-154 .

7. Bourbigot, S. and Le Bras, M. (1996). 4A Zeolite Synergistic Agent in New Flame Retardant Intumescent Formulations of Polyethylenes Polymers - Study of the Constituent Monomers , Polymer Degradation and Stability, 54: 275-287 .

8. Wang, J., Wei, P. and Hao, J. (2002). The Effect of Aluminosilicates on the Intumescent Ammonium Polyphosphate-Pentaerythritol Flame Retardant Systems: An X-ray Photoelectron Spectroscopy Study , ACS Symposium Series, 797: 150-162 .

9. Hao, J. (1998). Novel Flame Retardant Technology in Polypropylene Production , Plastics in China, 5: 76-81 .

10.

10. Xia, J., Xiao, C. and Wang, J. (2001). The Application of Artificial Neural Network (ANN) Technique to Formulation Design of Flame Retardant Polymers. I. Intumescent Flame Retardant PA-66 Composites , Journal of Fire Sciences, 19: 1-17 .

11.

11. Wu, S. (1999). New Approaches to Flame Retardancy of Copolymers (ABS/SBS): Grafting via Electron-Beam Technique, Doctoral Thesis, Beijing Institute of Technology, Beijing, China.

12.

12. Babrasukas, V. (1982). Development of Cone Calorimeter - A Bench Scale Rate of Heat Release Based on Oxygen Consumption, NBS-IR 82-2611 , US Nat. Bur. Stand, Gaithersburg .

13.

13. Wang, J. and Li, B. (1999). An XPS Investigation of Thermal Degradation and Charring in Combustion of PVC/Cu2O/MoO3 - the Synergy Between Cu2O and MoO3 in PVC , Polymer Degradation & Stability, 63: 279-285 .

14.

14. ASTM Standard D2863-91, (1992). Annual Book of ASTM Standards, American Society for Testing and Materials, Philadelphia, PA .

15.

15. Wang, J. and Wu, S. (2001). On the Flammability of the Electron-Beam-Induced Grafting of ABS and SBS Copolymers Studied by LOI/CONE/XPS , Journal of Fire Sciences, 19(MARCH/APRIL): 157-172 .

16.

16. Camino, G., Costa, L. and Martinasso, G. (1989). Intumescent Fire-Retardant Systems , Polymer Degradation and Stability, 23: 359-376 .

17.

17. Wei, P. and Wang, J. (2002). The Influence of Zeolites on the Thermal Degradation of IFR and IFR-PP , Polymer Materials Science and Engineering, 18(5): 124-127 (in Chinese).

18.

18. Wang, J., Du, J., Zhu, J. and Wilkie, C.A. (2002). An XPS Study of the Thermal Degradation and Flame Retardant Mechanism of Polystyrene-Clay Nanocomposites , Polym. Degrad. Stab., 77: 249-252 .

19.

19. Du, J., Zhu, J., Wilkie, C.A. and Wang, J. (2002). An XPS Study of the Thermal Degradation and Flame Retardant Mechanism of PMMA-clay Nanocomposites , Polym. Degrad. Stab., 77(3): 377-384 .