Flame‐retardant and mechanical properties of phenolic foams toughened with polyethylene glycol phosphates

Abstract

Three kinds of polyethylene glycol phosphates (PEGPs) toughening agents were synthesized by esterification of phosphorus pentoxide (P2O5) with polyethylene glycol and characterized by Fourier transform infrared spectra and 31P nuclear magnetic resonance. A series of lightweight phenolic foams toughened with different loadings of PEGPs were prepared. Optical microscopy results show that the addition of PEGPs with small molecular weight PEG improves the structural homogeneity of phenolic foams obviously. The flame retardancy of toughened phenolic foams was evaluated by using UL 94, limiting oxygen index, and cone calorimeter. The results indicate that the incorporation of PEGPs not only increases the toughness of phenolic foams but also improves their flame retardancy. Moreover, the thermal stability of PEGPs and the toughened foams was investigated by thermogravimetric analysis. Copyright © 2013 John Wiley & Sons, Ltd.

Preparation and mechanism of polyurethane prepolymer and boric acid co‐modified phenolic foam composite: Mechanical properties, thermal stability, and flame retardant properties

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Preparation and properties of a novel flame retardant polyurethane quasi‐prepolymer for toughening phenolic foam

“…Therefore, PF has been widely used in a broad range of applications, especially in construction. [1][2][3][4][5][6][7][8] However, PF is considerably brittle because they consist of lots of benzene rings, which limits its applications. [9][10][11][12] Thus, some research is required to improve the tougheness of PF for their comprehensive applications.…”

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One-step spontaneous synthesis of fluorescent carbon nanoparticles with thermosensitivity from polyethylene glycol

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