Research Progress in Halogen⁃free Flame Retardant Technology for Polypropylene

doi:10.19491/j.issn.1001-9278.2021.01.020

Abstract

Abstract:

This paper reviewed the recent research progress in the halogen-free flame-retardant technology for polypropylene （PP） and also analyzed the flame-retardant mechanism. The halogen-free flame retardants used for PP mainly included magnesium-aluminum flame retardants， phosphorus flame retardants， and intumescent flame retardants. In the research of halogen-free flame-retardant technology for PP， the development of charring agent and the research of compounding scheme were most popular. In this case， the charring agent for PP was introduced in detail.

Key words: flame retardant, polypropylene, charring agent, research progress

CLC Number:

TQ 325.1⁺4

TANG Wei, QIAN Lijun, QIU Yong, CHEN Yajun, XU Bo, ZHAO Zhen. Research Progress in Halogen⁃free Flame Retardant Technology for Polypropylene[J]. China Plastics, 2021, 35(1): 136-149.

Figures/Tables 21

Fig.1. Mechanism of intumescent flame retardant effect

Fig.2. Typical polyalcohol charring agents

Fig.3. Chemical structure of PEPA molecule

Fig.4. Chemical structure of BCPPO molecule

Fig.5. Chemical structure of SBCPO molecule

Fig.6. Chemical structure of DOPNP molecule

Fig.7. Chemical structure of SPSA molecule

Fig.8. Chemical structure of 1,3,5?trazine

Fig.9. Chemical structures of two small molecular triazine charring agents

Fig.10. Typical preparation steps for linear triazine charring agents

Fig.11. Chemical structures of three linear triazine charring agents

Fig.12. Chemical structure of PETAT molecule

Fig.13. Chemical structure of PTCA molecule

Fig.14. Chemical structure of ETPC molecule

Fig.15. Chemical structure of PEPAPC molecule

Fig.16. Chemical structures of two macromolecular triazine charring agents

Fig.17. Chemical structures of two macromolecular triazine charring agents with benzene ring structure

Fig.18. Chemical structure of HPCFA molecule

Fig.19. Chemical structure of THEIC molecule

Fig.20. Chemical structure of PEPAP molecule

Fig.21. Chemical structure of PDBPP molecule

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