Two novel phosphorus–nitrogen-containing halogen-free flame retardants of high performance for epoxy resin

With the increasing emphasis on environmental protection, the development of flame retardants for epoxy resin (EP) has tended to be non-toxic, efficient, multifunctional and systematic. Currently reported flame retardants have been capable of providing flame retardancy, heat resistance and thermal stability to EP. However, many aspects still need to be further improved. This paper reviews the development of EPs in halogen-free flame retardants, focusing on phosphorus flame retardants, carbon-based materials, silicon flame retardants, inorganic nanofillers, and metal-containing compounds. These flame retardants can be used on their own or in combination to achieve the desired results. The effects of these flame retardants on the thermal stability and flame retardancy of EPs were discussed. Despite the great progress on flame retardants for EP in recent years, further improvement of EP is needed to obtain numerous eco-friendly high-performance materials.

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Highly efficient halogen-free flame retardants of thermally-oxidized polyacrylonitrile copolymers containing bio-derived caffeic acid derivatives

Polymer Chemistry ◽

10.1039/d0py00854k ◽

2020 ◽

Vol 11 (41) ◽

pp. 6658-6669

Author(s):

Jongho Kim ◽

Nam-Ho You ◽

Bon-Cheol Ku

Keyword(s):

Caffeic Acid ◽

High Performance ◽

Flame Retardants ◽

Caffeic Acid Derivatives ◽

Highly Efficient ◽

Halogen Free

Polyacrylonitrile (PAN) copolymer with catechol comonomer is utilized as a precursor for the production of high-performance flame retarding fibers and is also widely used for clothing fibers.

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Flame-retardant halogen-free polymers using phosphorylated hexaglycidyl epoxy resin

High Performance Polymers ◽

10.1177/0954008316688759 ◽

2017 ◽

Vol 30 (2) ◽

pp. 202-210 ◽

Cited By ~ 2

Author(s):

Rasool Kheyrabadi ◽

Hossein Rahmani ◽

S Heydar Mahmoudi Najafi

Keyword(s):

Flame Retardant ◽

Epoxy Resin ◽

Phosphine Oxide ◽

Flame Retardancy ◽

High Performance ◽

Liquid Chromatography Mass Spectrometry ◽

Scanning Calorimetry ◽

Epoxy Monomer ◽

Ul 94 ◽

Halogen Free

Flame-retardant halogen-free epoxy resin, containing phosphorus and nitrogen atoms in the main chain, was synthesized through the curing of tris(3-(bis(oxiran-2-ylmethyl)amino)phenyl)phosphine oxide (HGE, hexaglycidyl epoxy monomer), starting from tris(3-aminophenyl) phosphine oxide (TAPO) and epichlorohydrin. The molecular structure of HGE with molecular weight 660 was confirmed using Fourier transform infrared, nuclear magnetic resonance, and liquid chromatography–mass spectrometry techniques. Epoxy equivalent weight determined by titration method was 120. The thermal curing behavior of the HGE/TAPO was investigated by differential scanning calorimetry. An intense exotherm due to curing reaction was observed in the temperature range from 123°C to 215°C. The HGE cured with TAPO, 4,4′-diaminodiphenylsulfone (DDS), and 1,5-diaminonaphthalene (DAN) and the thermal behaviors were studied by thermogravimetric analysis. The flame retardancy properties of the HGE/TAPO, DDS, and DAN were evaluated by vertical burning test (UL-94 V). The high performance cured epoxy resins showed high thermal stability and UL-94 V-0 flame retardancy rating.

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Synthesis of Novel Halogen-Free Phenol Based Polymers and their utilization as Flame Retardant in Polypropylene system

MRS Proceedings ◽

10.1557/opl.2013.175 ◽

2013 ◽

Vol 1492 ◽

pp. 161-166 ◽

Cited By ~ 2

Author(s):

Ruchi Bakshi ◽

Sethumadhavan Ravichandran ◽

Weeradech Kiratitanavit ◽

Jayant Kumar ◽

Ramaswamy Nagarajan

Keyword(s):

High Performance ◽

Flame Retardants ◽

Radical Scavenging ◽

Thermal Characterization ◽

Free Phenol ◽

New Class ◽

Char Formation ◽

New Varieties ◽

Halogen Free ◽

Halogenated Flame Retardants

ABSTRACTIncreasing awareness of toxicity of halogenated flame retardants (FRs) has resulted in stringent regulations that require the elimination of their use in plastics. Consequently, there is considerable interest for the development of new varieties of high performance FRs. Here, we report the synthesis of new class of polyphenol based FR additives. Preliminary investigations indicate that these FR materials can possibly work through a combination of radical scavenging and char-formation. The thermal stability and char yield of polyphenol samples were investigated by thermogravimetric analysis (TGA). Thermal characterization indicated that these polymers produce significant amount of carbonaceous char upon combustion.

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Synthesis, characterization and curing properties of a novel cyclolinear phosphazene-based epoxy resin for halogen-free flame retardancy and high performance

RSC Advances ◽

10.1039/c2ra20739g ◽

2012 ◽

Vol 2 (13) ◽

pp. 5789 ◽

Cited By ~ 54

Author(s):

Jia Liu ◽

Jiuying Tang ◽

Xiaodong Wang ◽

Dezhen Wu

Keyword(s):

Epoxy Resin ◽

Flame Retardancy ◽

High Performance ◽

Halogen Free

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Impact of halogen-free flame retardant with varied phosphorus chemical surrounding on the properties of diglycidyl ether of bisphenol-A type epoxy resin: synthesis, fire behaviour, flame-retardant mechanism and mechanical properties

RSC Advances ◽

10.1039/c6ra13168a ◽

2016 ◽

Vol 6 (64) ◽

pp. 59226-59236 ◽

Cited By ~ 46

Author(s):

Xiaomin Zhao ◽

Heeralal Vignesh Babu ◽

Javier Llorca ◽

De-Yi Wang

Keyword(s):

Mechanical Properties ◽

Bisphenol A ◽

Flame Retardant ◽

Epoxy Resin ◽

Flame Retardants ◽

Diglycidyl Ether ◽

Fire Behaviour ◽

Halogen Free

This work aimed to investigate the effect of two types ofphosphorus-containing flame retardants (P-FRs) with different chemical surroundings on flame-retardant efficiency for diglycidyl ester of bisphenol-A type epoxy (EP).

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Conductive Filament Formation in Printed Circuit Boards – Effects of Reflow Conditions and Flame Retardants

ISTFA 2009: Conference Proceedings from the 35th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2009p0301 ◽

2009 ◽

Author(s):

Bhanu Sood ◽

Michael Pecht

Keyword(s):

Flame Retardants ◽

Printed Circuit Boards ◽

Electrochemical Process ◽

Lead Free ◽

Circuit Boards ◽

Filament Formation ◽

Conductive Filament ◽

Printed Circuit ◽

Free Solder ◽

Halogen Free

Abstract Failures in printed circuit boards account for a significant percentage of field returns in electronic products and systems. Conductive filament formation is an electrochemical process that requires the transport of a metal through or across a nonmetallic medium under the influence of an applied electric field. With the advent of lead-free initiatives, boards are being exposed to higher temperatures during lead-free solder processing. This can weaken the glass-fiber bonding, thus enhancing conductive filament formation. The effect of the inclusion of halogen-free flame retardants on conductive filament formation in printed circuit boards is also not completely understood. Previous studies, along with analysis and examinations conducted on printed circuit boards with failure sites that were due to conductive filament formation, have shown that the conductive path is typically formed along the delaminated fiber glass and epoxy resin interfaces. This paper is a result of a year-long study on the effects of reflow temperatures, halogen-free flame retardants, glass reinforcement weave style, and conductor spacing on times to failure due to conductive filament formation.

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