Login Register Cart 0
Generic placeholder image

Current Applied Polymer Science

Editor-in-Chief

ISSN (Print): 2452-2716
ISSN (Online): 2452-2724

Back
Journal Home About Journal Editorial Board Journal Insight Current Issue Volumes/Issues
Subscribe
Research Article

Effect of Functionality of Organophosphorus Flame Retardants on Flammability and Thermal Stability of DGEBA-Based Epoxy Resin Nanocomposites

Author(s): Priyanka Bazzad and J.B. Dahiya*

Volume 4, Issue 3, 2021

Published on: 03 December, 2021

Page: [217 - 226] Pages: 10

DOI: 10.2174/2452271604666211104091336

Price: $65

conference banner
Abstract

Background: Epoxy resins have been extensively used in fire hazard environments, such as printed circuit boards, electrical isolation materials, adhesives, construction, and transportation due to their economically viable, simple processing. Therefore, the development of thermally stable and flame-retardant epoxy resin systems is essential.

Objective: The aim of the present study was to study the effect of the functionality of organophosphorus flame retardants on DGEBA-based epoxy resin nanocomposites on thermal stability and flame retardancy.

Methods: DGEBA (diglycidyl ether of bisphenol-A)-based epoxy resin nanocomposites having 2.0 wt% phosphorus were prepared with organophosphorus flame retardants with different functionalities by using an in-situ polymerization method. The flame retardant compounds uni-functional 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and bi-functional 2-(6-oxid-6Hdibenz [c, e] [1, 2] oxaphosphorin 6-yl) 1, 4-benzenediol (DOPO-HQ) were prepared. The thermal behavior of composites was studied by TG and DTA techniques. The flammability behavior was investigated by UL-94 and limiting oxygen index (LOI) tests.

Results: The XRD and TEM results showed the mixed dispersion of nanoclay platelets in an epoxy matrix. The thermal stability of the epoxy composite (EPDOPO-HQ) containing bi-functional DOPOHQ is increased by 16°C in comparison to the epoxy composite (EPDOPO) containing uni-functional DOPO. According to the TG analysis, the addition of nanoclay was observed to be more effective and synergistic with bi-functional DOPO-HQ as the EPDOPO-HQ/NC sample gains more resistance to degradation after around 450°C and also gave rise to a high char yield. Epoxy resin samples containing reactive flame retardants gave UL-94 V-0 rating, but further addition of 2.0 wt% nanoclay lowered the rating from V-0 to V-1.

Conclusions: TG analysis of the epoxy composite samples showed that the addition of nanoclay were observed to be synergistic with bi-functional flame retardant (DOPO-HQ) as the EPDOPO-HQ/NC sample gained more resistance to degradation after around 450°C due to the formation of mixed intercalated and exfoliated structure. The EPDOPO-HQ sample gave a high char yield with increased onset degradation temperature, high thermal stability as well as high flame retardancy.

Keywords: Epoxy nanocomposites, thermal stability, DOPO, nanoclay, flame retardants, limiting oxygen index.

« Previous Next »
Graphical Abstract

[1]
Troitzsch J. Plastics Flammable Handbook. 3rd ed. Munich: Hanser Publishers 2004.
[http://dx.doi.org/10.3139/9783446436695]
[2]
May CA, Tanaka Y. Epoxy Resins Chemistry and Technology. 2nd ed. New York: Marcel Dekker Inc 1988.
[3]
Levchik S, Weil ED. Thermal decomposition, combustion and flame-retardancy of epoxy resins- a review of the recent literature. Polym Int 2004; 53(12): 1901-29.
[http://dx.doi.org/10.1002/pi.1473]
[4]
Weil ED, Levchik S. A review of current flame retardant systems for epoxy resins. J Fire Sci 2004; 22(1): 25-40.
[http://dx.doi.org/10.1177/0734904104038107]
[5]
Levchik S, Piotrowski A, Weil E, Yao Q. New developments in flame retardancy of epoxy resins. Polym Degrad Stabil 2005; 88(1): 57-62.
[http://dx.doi.org/10.1016/j.polymdegradstab.2004.02.019]
[6]
Wang CS, Lin CH. Synthesis and properties of phosphorus-containing epoxy resins by novel method. J Polym Sci A Polym Chem 1999; 37: 3903-9.
[http://dx.doi.org/10.1002/(SICI)1099-0518(19991101)37:21<3903::AID-POLA4>3.0.CO;2-X]
[7]
Zhu Z, Wang L, Lin X, Dong L. Synthesis of a novel phosphorus-nitrogen flame retardant and its application in epoxy resin. Polym Degrad Stabil 2019; 169: 108981.
[http://dx.doi.org/10.1016/j.polymdegradstab.2019.108981]
[8]
Jangra P, Dahiya JB. Effects of nanoclay and flame retardant additives on glass transition temperature, thermal stability and flammability of epoxy composites. Mater Res Innov 2018; 22(7): 387-95.
[http://dx.doi.org/10.1080/14328917.2017.1325059]
[9]
Hussain M, Varley RJ, Mathys Z, Cheng YB, Simon GP. Effect of organo-phosphorus and nano-clay materials on the thermal and fire performance of epoxy resins. J Appl Polym Sci 2004; 91: 1233-53.
[http://dx.doi.org/10.1002/app.13267]
[10]
Xiao W, He P, Hu G, He B. Study on the flame-retardance and thermal Stability of the acid anhydride-cured epoxy resin flame-retarded by triphenyl phosphate and hydrated alumina. J Fire Sci 2001; 19: 369-77.
[http://dx.doi.org/10.1106/R4HN-GT2G-EWAR-733C]
[11]
Derouet D, Morvan F, Brosse JC. Chemical modification of epoxy resins by dialkyl(or aryl) phosphates: Evaluation of fire behavior and thermal stability. J Appl Polym Sci 1996; 62: 1855-68.
[http://dx.doi.org/10.1002/(SICI)1097-4628(19961212)62:11<1855::AID-APP10>3.0.CO;2-Y]
[12]
Liu Y-I, Pearce EM, Weil ED. Flame retardancy of dicyandiamide-crosslinked epoxy resins containing phenolphthalein structures and/or a phosphorus- containing additive. J Fire Sci 1999; 17: 240-58.
[http://dx.doi.org/10.1177/073490419901700306]
[13]
Perez R, Sandler JKW, Altstadt V, et al. Effect of DOP-based compounds on fire retardancy, thermal stability, and mechanical properties of DGEBA cured with 4,4′-DDS. J Mater Sci 2006; 41: 341-53.
[http://dx.doi.org/10.1007/s10853-005-2720-2]
[14]
Schartel B, Balaanovich AI, Braun U, et al. Pyrolysis of epoxy resins and fire behavior of epoxy resin composites flame-retarded with 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide additives. J Appl Polym Sci 2007; 104: 2260-9.
[http://dx.doi.org/10.1002/app.25660]
[15]
Schafer A, Seibold S, Lohstroh W, Walter O, Doring M. Synthesis and properties of flame-retardant epoxy resins based on DOPO and one of its analog DPPO. J Appl Polym Sci 2007; 105(2): 685-96.
[http://dx.doi.org/10.1002/app.26073]
[16]
Lin CH, Wang CS. Novel phosphorus-containing epoxy resins Part I. Synthesis and properties. Polymer (Guildf) 2001; 42: 1869-78.
[http://dx.doi.org/10.1016/S0032-3861(00)00447-X]
[17]
Wang CS, Lin CH. Synthesis and properties of phosphorus containing advanced epoxy resins. J Appl Polym Sci 2000; 75: 429-36.
[http://dx.doi.org/10.1002/(SICI)1097-4628(20000118)75:3<429::AID-APP13>3.0.CO;2-U]
[18]
Liu YL. Phosphorous-containing epoxy resins from a novel synthesis route. J Appl Polym Sci 2002; 83: 1697-701.
[http://dx.doi.org/10.1002/app.10092]
[19]
Zammarano M. Flame Retardant Nanocompositess New Jersy John Wiley & Sons. 2007; p. 235.
[http://dx.doi.org/10.1002/9780470109038.ch9]
[20]
Becker O, Cheng YB, Varley RJ, Simon GP. Layered silicate nanocomposites based on various high-functionality epoxy resin: The influence of cure temperature on morphology, mechanical properties and free volume. Macromolecules 2003; 36: 1616-25.
[http://dx.doi.org/10.1021/ma0213448]
[21]
Camino G, Tartaglione G, Frache A, Manferti C, Costa G. Thermal and combustion behaviour of layered silicate-epoxy nanocompostes. Polym Degrad Stabil 2005; 90: 354-62.
[http://dx.doi.org/10.1016/j.polymdegradstab.2005.02.022]
[22]
Shieh JY, Wang CS. Effect of the organophosphate structure on the physical and flame-retardant properties of an epoxy resin. J Polym Sci A Polym Chem 2002; 40: 369-78.
[http://dx.doi.org/10.1002/pola.10121]
[23]
Wang X, Zhang Q. Synthesis, characterization, and cure properties of phosphorus-containing epoxy resins for flame retardance. Eur Polym J 2004; 40(2): 385-95.
[http://dx.doi.org/10.1016/j.eurpolymj.2003.09.023]
[24]
Wang CS, Lee MC. Synthesis and properties of epoxy resins containing 2-(6-oxid-6H-dibenz(c,e)(1,2) oxaphospharin-6-yl) 1,4-benzenediol (II). Polymer (Guildf) 2000; 41(10): 3631-8.
[http://dx.doi.org/10.1016/S0032-3861(99)00541-8]
[25]
Tidjani A, Wilkie CA. Photo-oxidation of polymeric-inorganic nanocomposites: Chemical, thermal stability and fire retardancy investigations. Polym Degrad Stabil 2001; 74: 33-7.
[http://dx.doi.org/10.1016/S0141-3910(01)00061-1]
[26]
Wang Q, Song C, Lin W. Study of the exfoliation process of epoxy–clay nanocomposites by different curing agents. J Appl Polym Sci 2003; 90(2): 511-7.
[http://dx.doi.org/10.1002/app.12689]
[27]
Gu J, Dang J, Wu Y, Xie C, Han Y. Flame-Retardant, thermal, mechanical and dielectric properties of structural non-halogenated epoxy resin composites. Polym Plast Technol Eng 2012; 51: 1198-203.
[http://dx.doi.org/10.1080/03602559.2012.694951]
[28]
Kornmann X, Lindberg H, Berglund LA. Synthesis of epoxy-clay nanocomposites: Influence of the nature of the clay on structure. Polymer (Guildf) 2001; 42(4): 1303-10.
[http://dx.doi.org/10.1016/S0032-3861(00)00346-3]
[29]
Grassie N, Guy MI, Tennent NH. Degradation of epoxy polymers: Part-4 thermal degradation of bisphenol-A diglycidyl ether cured with ethylene diamine. Polym Degrad Stabil 1986; 14(2): 125-37.
[http://dx.doi.org/10.1016/0141-3910(86)90011-X]
[30]
Qi B, Zhang QX, Bannister M, Mai Y-W. Investigation of the mechanical properties of DGEBA-based epoxy resin with nanoclay additives. Compos Struct 2006; 75(1): 514-9.
[http://dx.doi.org/10.1016/j.compstruct.2006.04.032]

Rights & Permissions Print Cite
Article Metrics
8
1
© 2024 Bentham Science Publishers | Privacy Policy