Restricted accessResearch articleFirst published online 2023-9
Synthesis and characterization of a novel P/N containing flame retardant and its effect on flame-retardancy,thermal and mechanical properties of epoxy/clay nanocomposites
A P/N containing flame retardant DOPO-QN was synthesized by a reaction between 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and 8-hydroxyquinoline (QN). Its chemical structure was characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) like 1H, 13C, 31P NMR, and high-resolution mass spectrometry (HRMS) techniques. The synthesized DOPO-QN was employed as an additive type flame retardant in combination with clay nanomer 1.34TCN (NC) in diglycidyl ether of bisphenol A/4,4ʹ-diaminodiphenlsulfone (DGEBA/DDS) to synthesize epoxy thermosets. The fire behavior of synthesized epoxy thermosets was studied by UL-94, limiting oxygen index (LOI), and cone calorimeter tests. The EP/DOPO-QN (1.5%P)/NC sample passed the UL-94 test with a V-0 rating and LOI value of 26.5%. A decrease in peak heat released, carbon monoxide, and carbon dioxide emissions was observed in the cone calorimeter test. Thermogravimetric analysis (TGA) of epoxy thermosets showed an increase in thermal stability at a higher temperature range on the formation of nanocomposites. Also, a remarkable improvement in storage modulus was observed for the EP/DOPO-QN (1.5%P)/NC sample containing 2.0% NC in dynamic mechanical analysis (DMA).
ShiehJYWangCS. Synthesis of novel flame retardant epoxy hardeners and properties of cured products. Polymer2001; 42: 7617–7625. DOI: 10.1016/s0032-3861(01)00257-9
2.
WangQShiW. Kinetics study of thermal decomposition of epoxy resins containing flame retardant components. Polym Degrad Stab2006; 91: 1747–1754. DOI: 10.1016/j.polymdegradstab.2005.11.018
3.
WuKSongLHuY, et al.Synthesis and characterization of a functional polyhedral oligomeric silsesquioxane and its flame retardancy in epoxy resin. Prog Org Coat2009; 65: 490–497. DOI: 10.1016/j.porgcoat.2009.04.008
4.
NakamuraYYamaguchiMOkuboM, et al.Effects of particle size on mechanical and impact properties of epoxy resin filled with spherical silica. J Appl Polym Sci1992; 45: 1281–1289. DOI: 10.1002/app.1992.070450716
5.
DengPShiYLiuY, et al.Solidifying process and flame retardancy of epoxy resin cured with boron-containing phenolic resin. Appl Surf Sci2018; 427: 894–904. DOI: 10.1016/j.apsusc.2017.07.278
6.
JangraPDahiyaJB. Effects of nanoclay and flame retardant additives on glass transition temperature, thermal stability and flammability of epoxy composites. Mater Res Innov2018; 22: 387–395. DOI: 10.1080/14328917.2017.1325059
7.
LinCHLinHTChangSL, et al.Benzoxazines with tolyl, p-hydroxyphenyl or p-carboxyphenyl linkage and the structure–property relationship of resulting thermosets. Polymer2009; 50: 2264–2272. DOI: 10.1016/j.polymer.2009.02.042
8.
SpontonMMercadoLARondaJC, et al.Preparation, thermal properties and flame retardancy of phosphorus-and silicon-containing epoxy resins. Polym Degrad Stab2008; 93: 2025–2031. DOI: 10.1016/j.polymdegradstab.2008.02.014
9.
EkpeODChooGBarceloD, et al.Introduction of emerging halogenated flame retardants in the environment. Compr Anal Chem2020; 88: 1–39. DOI: 10.1016/bs.coac.2019.11.002
10.
ShawSDBlumAWeberR, et al.Halogenated flame retardants: do the fire safety benefits justify the risks?Rev Environ Health2010; 25: 261–305.
11.
ZhangYYuBWangB, et al.Highly effective P-P synergy of a novel DOPO-based flame retardant for epoxy resin. Ind Eng Chem Res2017; 56: 1245–1255. DOI: 10.1021/acs.iecr.6b04292
12.
GreenJ. A review of phosphorus-containing flame retardants. J Fire Sci1992; 10: 470–487. DOI: 10.1177/073490419201000602
13.
RenHSunJWuB, et al.Synthesis and properties of a phosphorus-containing flame retardant epoxy resin based on bis-phenoxy (3-hydroxy) phenyl phosphine oxide. Polym Degrad Stab2007; 92: 956–961. DOI: 10.1016/j.polymdegradstab.2007.03.006
14.
UnluSMDoganSDDoganM. Comparative study of boron compounds and aluminum trihydroxide as flame retardant additives in epoxy resin. Polym Adv Technol2014; 25: 769–776. DOI: 10.1002/pat.3274
15.
MartinCLligadasGRondaJC, et al.Synthesis of novel boron-containing epoxy–novolac resins and properties of cured products. J Polym Sci A Polym Chem2006; 44: 6332–6344. DOI: 10.1002/pola.21726
16.
ZangLWagnerSCiesielskiM, et al.Novel star‐shaped and hyperbranched phosphorus‐containing flame retardants in epoxy resins. Polym Adv Technol2011; 22: 1182–1191. DOI: 10.1002/pat.1990
17.
QiuYQianLXiW. Flame-retardant effect of a novel phosphaphenanthrene/triazine-trione bi-group compound on an epoxy thermoset and its pyrolysis behaviour. RSC Adv2016; 6: 56018–56027. DOI: 10.1039/c6ra10752d
18.
LeuTSWangCS. Synergistic effect of a phosphorus–nitrogen flame retardant on engineering plastics. J Appl Polym Sci2004; 92: 410–417. DOI: 10.1002/app.13689
19.
SudhakaraPKannanPObireddyK, et al.Organophosphorus and DGEBA resins containing clay nanocomposites: flame retardant, thermal, and mechanical properties. J Mater Sci2011; 46: 2778–2788. DOI: 10.1007/s10853-010-5152-6
LiuZQiuYQianL, et al.Strengthen flame retardancy of epoxy thermoset by montmorillonite particles adhering phosphorus‐containing fragments. J Appl Polym Sci2020; 137: 47500. DOI: 10.1002/app.47500
22.
RajaeiMKimNKBickertonS, et al.A comparative study on effects of natural and synthesised nano-clays on the fire and mechanical properties of epoxy composites. Composites Part B: Engineering2019; 165: 65–74. DOI: 10.1016/j.compositesb.2018.11.089
23.
ZhangSJiangYSunY, et al.Preparation of flame retardant and conductive epoxy resin composites by incorporating functionalized multi‐walled carbon nanotubes and graphite sheets. Polym Adv Technol2021; 32: 2093–2101. DOI: 10.1002/pat.5239
24.
LiuQZhaoYGaoS, et al.Recent advances in the flame retardancy role of graphene and its derivatives in epoxy resin materials. Composites Part A: Applied Science and Manufacturing2021; 149: 106539. DOI: 10.1016/j.compositesa.2021.106539
25.
KiliarisPPapaspyridesCD. Polymer/layered silicate (clay) nanocomposites: an overview of flame retardancy. Prog Polym Sci2010; 35: 902–958. DOI: 10.1016/j.progpolymsci.2010.03.001
26.
LuCGaoXPYaoDH, et al.Improving flame retardancy of linear low-density polyethylene/nylon 6 blends via controlling localization of clay and intumescent flame-retardant. Polym Degrad Stab2018; 153: 75–87. DOI: 10.1016/j.polymdegradstab.2018.04.022
27.
KongQWuTZhangH, et al.Improving flame retardancy of IFR/PP composites through the synergistic effect of organic montmorillonite intercalation cobalt hydroxides modified by acidified chitosan. Appl Clay Sci2017; 146: 230–237. DOI: 10.1016/j.clay.2017.05.048
28.
ZhuTTZhouCHKabweFB, et al.Exfoliation of montmorillonite and related properties of clay/polymer nanocomposites. Appl Clay Sci2019; 169: 48–66. DOI: 10.1016/j.clay.2018.12.006
29.
LiLZhangYLiaoX, et al.Structure and properties of poly (oxypropylene) diamine intercalated montmorillonite/epoxy composites. Journal of Macromolecular Science Part B2019; 58: 877–889. DOI: 10.1080/00222348.2019.1662989
30.
HeXZhangWYangR. The characterization of DOPO/MMT nanocompound and its effect on flame retardancy of epoxy resin. Composites Part A: Applied Science and Manufacturing2017; 98: 124–135. DOI: 10.1016/j.compositesa.2017.03.020
31.
YanWYuJZhangM, et al.Enhanced flame retardancy of epoxy resin containing a phenethyl-bridged DOPO derivative/montmorillonite compound. J Fire Sci2018; 36: 47–62. DOI: 10.1177/0734904117740820
32.
WangPFuXKanY, et al.Two high-efficient DOPO-based phosphonamidate flame retardants for transparent epoxy resin. High Perform Polym2019; 31: 249–260. DOI: 10.1177/0954008318762037
33.
PengWNieSBXuYX, et al.A tetra-DOPO derivative as highly efficient flame retardant for epoxy resins. Polym Degrad Stab2021; 193: 109715. DOI: 10.1016/j.polymdegradstab.2021.109715
34.
Le CorreSSCouthon-GourvèsHBerchelM, et al.Atherton–Todd reaction: mechanism, scope and applications. Beilstein J Org Chem2014; 10: 1166–1196. DOI: 10.3762/bjoc.10.117
35.
WangXHuYSongL, et al.Thermal degradation mechanism of flame retarded epoxy resins with a DOPO-substitued organophosphorus oligomer by TG-FTIR and DP-MS. J Anal Appl Pyrolysis2011; 92: 164–170. DOI: 10.1016/j.jaap.2011.05.006
36.
YamunadeviVPalaniradjaKThiagarajanA, et al.Characterization and dynamic mechanical analysis of woven roven glass fiber/cerium-zirconium oxide epoxy nanocomposite materials. Mater Res Express2019; 6: 095057. DOI: 10.1088/2053-1591/ab2f64
37.
WanJGanBLiC, et al.A novel biobased epoxy resin with high mechanical stiffness and low flammability: synthesis, characterization and properties. J Mater Chem A2015; 3: 21907–21921. DOI: 10.1039/c5ta02939b
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
