Synthesis of DOPO‐g‐GPTS modified wood fiber and its effects on the properties of composite phenolic foams

Abstract

A novel 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) grafted γ-glycidoxy propyl trimethoxy silane (GPTS) was synthesized and introduced on the surface of wood fiber (WF). DOPO-g-GPTS modified wood fiber (DGMWF) was then used to prepare DGMWF composite phenolic foam (DGMWFCPF). The structures of DOPO-g-GPTS were verified by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance ( 1 H-NMR). The structure of DGMWF was confirmed by FT-IR. The crystallinity of DGMWF was slightly increased, however, the diffraction peak positions were basically unchanged. In addition, the thermal stability was dramatically improved, and T i and T max increased by 26.6 and 33.2 C respectively. The carbon residue (800 C) was reduced by 3.65%. By comparison with pure phenolic foam, the mechanical properties, flame retardancy of DGMWFCPF were increased. No significant changes were observed for the microstructure. By comprehensive analysis, the interfacial compatibility was significantly improved between DGMWF and phenolic resin. The suitable dosage of DGMWF was 4-6%.

Preparation and Characterization of DOPO-ITA Modified Ethyl Cellulose and Its Application in Phenolic Foams

“…Therefore the heat resistance of CPFs was reduced. Otherwise, phosphorus (in DIMEC) was introduced into the CPF, which could migrate to the external char layer, form a thick and compact thermal barrier, and could delay the process of degradation [53]. So the carbon residues (800 °C) of CPFs were improved.…”

A comprehensive review on phenol‐formaldehyde resin‐based composites and foams

“…[86] F I G U R E 8 Mechanical properties of modified wood fiber reinforced phenolic foam. [103] were used to examine the impact of GO nanosheets on the heat transmission mechanism. The investigations on the kinetics of nanocomposite aerogels at high temperatures were used to analyze processes connected with their structure using GO nanosheets.…”

“…As a reinforcement, 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) grafted ‐glycidoxy propyl trimethoxy silane (GPTS) modified wood fiber (DGMWF) was used to improve the fire retardant behavior of phenolic foam. [ 103 ] The morphology, mechanical properties, thermal stability, and fire‐retardant properties of the prepared foam were analyzed (Figure 8). The addition of 4% and 6% of DGMWF to phenolic foam enhanced the bending strength compared to neat foam.…”

Synthesis and Characterization of DOPO-g-CNSL and Its Effect on the Properties of Phenolic Foams

“…4. For DOPO, the signal around 6.56 to 8.86 ppm was corresponded to the phenyl protons [28][29][30][31]. For CNSL, the chemical shifts of H a , H b , H c , H d and H e were observed at 0.97 ppm, 1.38 ppm, 2.10 ppm, 1.64 ppm and 2.60 ppm respectively, and the signal around 5.44 ppm (H f ) was corresponded to double bonds protons [10].…”

“…It might be explained that Ti of DOPO-g-CNSL (267.5°C,in Fig. 5) was more than that of DCMPFs, otherwise, phosphorus (in DOPO-g-CNSL) was introduced into the DCMPFs, which could migrate to the external char layer, form a thick and compact thermal barrier when the DCMPFs were flamed or heated, which covered on the surface of DCMPFs prevented oxygen and heat getting into the foams, further enhanced the thermal stability of DCMPFs [34][35][36][37][38]. Although, the introduction of phosphorus was conducive to carbon formation.…”