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Licensed Unlicensed Requires Authentication Published by De Gruyter November 16, 2021

Synergistic Flame-Retardant Effect of Aluminum Diethyl Phosphinate in PP/IFR System and the Flame-Retardant Mechanism

  • J.-L. Li , C.-T. Gao , X. Sun , S.-G. Peng , Y.-W. Wang and S.-H. Qin


Synergistic flame-retardant effect of aluminum diethyl phosphinate (AlPi) in intumescent flame retardant polypropylene (PP/IFR) system and the flame-retardant mechanism were investigated. The flame retardancy of PP/IFR/AlPi (the mass ratio of IFR to AlPi is 2 : 1) was the best, which was proved by the results of the limiting oxygen index (LOI) test, UL-94 test, and cone calorimeter test ( CCT) test. Here, the LOI value of the sample was as high as 34% and passed the V–0 rating in UL–94 test. The peak heat release rate (PHRR) decreased by 92.57%, the total heat release (THR) reduced by 90.52%. Thermogravimetric (TGA) data showed that the introduction of AlPi improved thermal stability and changed the thermal degradation behavior of PP/IFR composites. Interestingly, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDXS) and laser Raman spectroscopy (LRS) proved that PP/IFR/AlPi had formed more residual carbon, but the flame retardancy was worse than PP/IFR/AlPi. This is because when the mass ratio of IFR to AlPi is 2 : 1, the synergy between IFR and AlPi was significant, gas-phase flame retardant and condensed-phase flame retardant reached a balance and obtained the best flame retardant effect.

Shuhao Qin, College of Materials Science and Metallurgy Engineering, Guizhou University, Guiyang, PRC


This research was funded by National Natural Science Foundation of China, grant number was 52063007; Guizhou Province High-level Innovative Talent Project, grant number was Qianke He Platform Talent [2020]6024; Guizhou Province Science and Technology Support Plan Project, grant number was Qianke He Support [2019] 2029; Guizhou Province Science and Technology Support Plan Project, grant number was Qianke He Support (2020) No. 4Y021; Guizhou postgraduate research fund, grant number was Guizhou Education Cooperation YJSCXJH[2019]003.


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Received: 2020-12-16
Accepted: 2021-04-13
Published Online: 2021-11-16

© 2021 Walter de Gruyter GmbH, Berlin/Boston, Germany

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