Facile preparation of uniform polydopamine particles and its application as an environmentally friendly flame retardant for biodegradable polylactic acid

The demand for environmentally benign flame retardants for biodegradable polymers has become particularly necessary due to their inherently “green” nature. This work reports intrinsically non-toxic polydopamine (PDA) particles as an efficient and environmentally friendly flame retardant for polylactic acid (PLA). 5 wt% PDA loading resulted in a 22% reduction in the peak heat release rate, 34.7% increase in the fire performance index, and lower CO2 production compared to neat PLA. A limiting oxygen index (LOI) value of 27.5% and a V-2 rating was achieved in the UL-94 vertical burning test. Highly aggregated amorphous particulate char was formed with the increasing content of PDA, and a significant reduction in evolved pyrolysis gaseous products was achieved for the PLA/PDA composites as compared with control PLA. This work provides important insight into the potential commercial application of PDA alone as an efficiently green, environmentally benign flame retardant for bioplastic PLA.

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Synergistic Flame Retardant Effect of Barium Phytate and Intumescent Flame Retardant for Epoxy Resin

Polymers ◽

10.3390/polym13172900 ◽

2021 ◽

Vol 13 (17) ◽

pp. 2900

Author(s):

Linyuan Wang ◽

Yue Wei ◽

Hongbo Deng ◽

Ruiqi Lyu ◽

Jiajie Zhu ◽

...

Keyword(s):

Flame Retardant ◽

Epoxy Resin ◽

Flame Retardancy ◽

Barium Carbonate ◽

Environmentally Friendly ◽

Intumescent Flame Retardant ◽

Limiting Oxygen Index ◽

Application Range ◽

Peak Heat Release Rate ◽

Synergistic Flame Retardant

Recently, widespread concern has been aroused on environmentally friendly materials. In this article, barium phytate (Pa-Ba) was prepared by the reaction of phytic acid with barium carbonate in deionized water, which was used to blend with intumescent flame retardant (IFR) as a flame retardant and was added to epoxy resin (EP). Afterward, the chemical structure and thermal stability of Pa-Ba were characterized by Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA), respectively. On this basis, the flammability and flame retardancy of EP composites were researched. It is shown that EP/14IFR/2Ba composite has the highest limiting oxygen index (LOI) value of 30.7%. Moreover, the peak heat release rate (PHRR) of EP/14IFR/2Ba decreases by 69.13% compared with pure EP. SEM and Raman spectra reveal the carbonization quality of EP/14IFR/2Ba is better than that of other composites. The results prove that Pa-Ba can cooperate with IFR to improve the flame retardancy of EP, reducing the addition amount of IFR in EP, thus expanding the application range of EP. In conclusion, adding Pa-Ba to IFR is a more environmentally friendly and efficient method compared with others.

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The Preparation and Characterization of Polylactic Acid Composites with Chitin-Based Intumescent Flame Retardants

Polymers ◽

10.3390/polym13203513 ◽

2021 ◽

Vol 13 (20) ◽

pp. 3513

Author(s):

Xiaodong Jin ◽

Suping Cui ◽

Shibing Sun ◽

Jun Sun ◽

Sheng Zhang

Keyword(s):

Polylactic Acid ◽

Flame Retardants ◽

Mechanism Analysis ◽

Limiting Oxygen Index ◽

Melt Compounding ◽

Gas Source ◽

Charring Agent ◽

Peak Heat Release Rate ◽

Intumescent Flame Retardants

In this work, a novel intumescent flame retardant (IFR) system was fabricated by the introduction of chitin as a green charring agent, ammonium polyphosphate (APP) as the acid source, and melamine (MEL) as the gas source. The obtained chitin-based IFR was then incorporated into a polylactic acid (PLA) matrix using melt compounding. The fire resistance of PLA/chitin composites was investigated via the limiting oxygen index (LOI), UL-94 vertical burning, and cone calorimeter (CONE) tests. The results demonstrated that the combination of 10%APP, 5%chitin and 5%MEL could result in a 26.0% LOI, a V-0 rating after UL and a 51.2% reduction in the peak heat release rate during the CONE test. Based on the mechanism analysis from both the morphology and the chemical structure of the char, it was suggested that chitin was a promising candidate as a charring agent for chitin reacted with APP and MEL with the formation of an intumescent layer on the surface.

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The Flammability of Polyacrylonitrile and Its Copolymers I. The Flammability Assessment Using Pressed Powdered Polymer Samples

Journal of Fire Sciences ◽

10.1177/073490419301100505 ◽

1993 ◽

Vol 11 (5) ◽

pp. 442-456 ◽

Cited By ~ 14

Author(s):

Jun Zhang ◽

Michael E. Hall ◽

A. Richard Horrocks

Keyword(s):

Flame Retardant ◽

Flame Retardancy ◽

Flame Retardants ◽

Oxygen Index ◽

Char Residue ◽

Acrylic Polymer ◽

Limiting Oxygen Index ◽

Convenient Means ◽

Burning Rates ◽

Polymer Flammability

This paper is the first in a series of four which investigates the burning behaviour and the influence of flame retardant species on the flam mability of fibre-forming polymer and copolymers of acrylonitrile. A pressed powdered polymer sheet technique is described that enables a range of polymer compositions in the presence and absence of flame retardants to be assessed for limiting oxygen index, burning rate and char residue deter minations. The method offers a rapid, reproducible and convenient means of screening possible flame retardant systems, and LOI values compare favourably with those of films and fabrics comprising the same polymeric type. Burning rates, however, are sensitive to changes in physical sample character such as form (film vs. powder sheet) and density. Thus the technique forms an excellent basis for the generation of burning data which will enable comprehensive studies of acrylic polymer flammability and flame retardancy to be undertaken.

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A Facile Preparation of Environmentally-Benign and Flame-Retardant Coating on Wood by Comprising Polysilicate and Boric Acid

10.21203/rs.3.rs-528431/v1 ◽

2021 ◽

Author(s):

Kaihao Wang ◽

Shuheng Wang ◽

Dan Meng ◽

Dong Chen ◽

Chenzhong Mu ◽

...

Keyword(s):

Boric Acid ◽

Flame Retardant ◽

Wood Sample ◽

Low Cost ◽

Treated Wood ◽

Environmentally Benign ◽

Wood Combustion ◽

Flame Resistance ◽

Limiting Oxygen Index ◽

Index Value

Abstract For the sake of direct using on the built wooden buildings, a green flame resistance coating comprising sodium polysilicate (SPS) and boric acid was prepared. With weight gain of only 10 wt.%, the treated wood sample (SPS/B-wood) performed improved limiting oxygen index value of 40.3% and passed the V-0 rating in UL-94 test. Additionally, the total heat release, total smoke production and peak carbon monoxide production of SPS/B-wood sample were decreased by 24.5%, 36.0% and 59.4% respectively, compared with that of control wood sample. The residue of SPS/B-wood sample was increased to 54.0% from 18.4% of control wood sample at 800oC in the thermogravimetry analysis. The flame retardant mechanism was suggested that SPS and boric acid formed Si-O-B and Si-O-Si contained structures, isolating the heat and smoke transfer during wood combustion. Notably, NaOH, introduced by the SPS/B coating, catalyzed the lignin to form compact and high-quality char. To conclude, this low-cost and easily-operated coating has a promising future utilizing in the villages with dense wood buildings.

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Flammability and mechanical properties of poly(styrene–butadiene–styrene) copolymer–containing intumescent flame retardants

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705715614061 ◽

2015 ◽

Vol 30 (6) ◽

pp. 816-826 ◽

Cited By ~ 7

Author(s):

Yiren Huang ◽

Jianwei Yang ◽

Zhengzhou Wang

Keyword(s):

Mechanical Properties ◽

Flame Retardant ◽

Flame Retardants ◽

Oxygen Index ◽

Limiting Oxygen Index ◽

Styrene Butadiene Styrene ◽

Flame Retardant Properties ◽

Intumescent Flame Retardants ◽

Styrene Butadiene ◽

Butadiene Styrene

Flame-retardant properties of ammonium polyphosphate (APP) and its two microcapsules, APP with a shell of melamine–formaldehyde (MF) resin (MFAPP) and APP with a shell of epoxy resin (EPAPP), were studied in styrene–butadiene–styrene (SBS). The results indicate that APP after the microencapsulation leads to an increase in limiting oxygen index in SBS compared with APP. When dipentaerythritol is incorporated into the SBS composites containing the APP microcapsules, a further improvement in flame retardancy of the composites is observed. The microencapsulation does not result in much improvement of mechanical properties. Moreover, the effect of a compatibilizer (SBS grafted with maleic anhydride) on flame-retardant and mechanical properties of SBS/APP composites was investigated.

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Synthesis and Application of a Novel Intumescent Flame Retardant Containing Ferrocenyl

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1033-1034.931 ◽

2014 ◽

Vol 1033-1034 ◽

pp. 931-936

Author(s):

Cong Yan Chen ◽

Rui Lan Fan ◽

Guan Qun Yun

Keyword(s):

Thermal Stability ◽

Flame Retardant ◽

Flame Retardants ◽

Intumescent Flame Retardant ◽

Limiting Oxygen Index ◽

Good Thermal Stability ◽

H Nmr ◽

Positive Effect ◽

Thermal Stability Of ◽

Phosphate Groups

A novel intumescent flame retardant (IFR) containing ferrocene and caged bicyclic phosphate groups, 1-oxo-4-[4'-(ferrocene carboxylic acid phenyl ester)] amide-2, 6, 7-trioxa-1-phosphabicyclo- [2.2.2] octane (PFAM), was successfully synthesized. The synthesized PFAM were added to flammable polyurethane (PU) as flame retardants and smoke suppressants. The structure of PFAM was characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H NMR) and elemental analysis. Thermal stability of PFAM was tested by themogravimetric analysis (TGA). The results revealed that PFAM had good thermal stability and high char weight, the char weight up to 54% at 600 °C. Flammability properties of PU/PFAM composites were investigated by limiting oxygen index (LOI) test and UL-94 test, respectively. The results of LOI tests showed that the addition of PFAM enhanced flame retardancy of PU. When the content of PFAM reaches to 3%, the LOI value is 22.2. The morphologies of the char for PU and PU/3% PFAM composite can be obtained after LOI testing were examined by SEM. The results demonstrated that PFAM could promote to form the compact and dense intumescent char layer. Experiments showed that, the PFAM application of polyurethane showed positive effect.

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Development of Bioepoxy Resin Microencapsulated Ammonium-Polyphosphate for Flame Retardancy of Polylactic Acid

Molecules ◽

10.3390/molecules24224123 ◽

2019 ◽

Vol 24 (22) ◽

pp. 4123 ◽

Cited By ~ 1

Author(s):

Kata Decsov ◽

Katalin Bocz ◽

Beáta Szolnoki ◽

Serge Bourbigot ◽

Gaëlle Fontaine ◽

...

Keyword(s):

Ftir Spectroscopy ◽

Flame Retardant ◽

Polylactic Acid ◽

Ammonium Polyphosphate ◽

Cone Calorimetry ◽

Scanning Calorimetry ◽

Electron Microscopic ◽

Sem Images ◽

Limiting Oxygen Index ◽

Microencapsulated Ammonium Polyphosphate

Ammonium-polyphosphate (APP) was modified by microencapsulation with a bio-based sorbitol polyglycidyl ether (SPE)-type epoxy resin and used as a flame retardant additive in polylactic acid (PLA) matrix. The bioresin-encapsulated APP (MCAPP) particles were characterized using Fourier transform infrared (FTIR) spectroscopy and Raman mapping, particle size distribution was determined by processing of scanning electron microscopic (SEM) images. Interaction between the APP core and the bioresin shell was revealed by combined thermogravimetric analysis (TGA)‑FTIR spectroscopy. The APP to SPE mass ratio of 10 to 2 was found to be optimal in terms of thermal, flammability, and mechanical properties of 15 wt% additive containing biocomposites. The bioresin shell effectively promotes the charring of the APP-loaded PLA composites, as found using TGA and cone calorimetry, and eliminates the flammable dripping of the specimens during the UL-94 vertical burning tests. Thus, the V-0 rating, the increased limiting oxygen index, and the 20% reduced peak of the heat release rate was reached compared to the effects of neat APP. Furthermore, better interfacial interaction of the MCAPP with PLA was indicated by differential scanning calorimetry and SEM observation. The stiff interphase resulted in increased modulus of these composites. Besides, microencapsulation provided improved water resistance to the flame retardant biopolymer system.

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Self-Extinguishing Resin Transfer Molding Composites Using Non-Fire-Retardant Epoxy Resin

Materials ◽

10.3390/ma11122554 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2554 ◽

Cited By ~ 3

Author(s):

Zhi Geng ◽

Shuaishuai Yang ◽

Lianwang Zhang ◽

Zhenzhen Huang ◽

Qichao Pan ◽

...

Keyword(s):

Flame Retardant ◽

Flame Retardants ◽

Resin Transfer Molding ◽

Fire Retardant ◽

Functional Materials ◽

Building Blocks ◽

Fire Retardancy ◽

Limiting Oxygen Index ◽

Transfer Molding ◽

Halogen Free

Introducing fire-retardant additives or building blocks into resins is a widely adopted method used for improving the fire retardancy of epoxy composites. However, the increase in viscosity and the presence of insoluble additives accompanied by resin modification remain challenges for resin transfer molding (RTM) processing. We developed a robust approach for fabricating self-extinguishing RTM composites using unmodified and flammable resins. To avoid the effects on resin fluidity and processing, we loaded the flame retardant into tackifiers instead of resins. We found that the halogen-free flame retardant, a microencapsulated red phosphorus (MRP) additive, was enriched on fabric surfaces, which endowed the composites with excellent fire retardancy. The composites showed a 79.2% increase in the limiting oxygen index, a 29.2% reduction in heat release during combustion, and could self-extinguish within two seconds after ignition. Almost no effect on the mechanical properties was observed. This approach is simple, inexpensive, and basically applicable to all resins for fabricating RTM composites. This approach adapts insoluble flame retardants to RTM processing. We envision that this approach could be extended to load other functions (radar absorbing, conductivity, etc.) into RTM composites, broadening the application of RTM processing in the field of advanced functional materials.

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Preparation and Properties of Halogen-Free Flame Retardant Polyurethane Foams

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.418-420.540 ◽

2011 ◽

Vol 418-420 ◽

pp. 540-543 ◽

Cited By ~ 2

Author(s):

Ding Meng Chen ◽

Yi Ping Zhao ◽

Jia Jian Yan ◽

Li Chen ◽

Zhi Zhi Dong ◽

...

Keyword(s):

Flame Retardant ◽

Flame Retardants ◽

Oxygen Index ◽

Mechanical Analysis ◽

Polyurethane Foams ◽

Dimethyl Methylphosphonate ◽

Limiting Oxygen Index ◽

Layer Composite ◽

Halogen Free ◽

Thermal Stable

Polyurethane foams (PUFs) filled with several halogen-free flame retardants and composite halogen-free flame retardants were prepared. The flame retardant, thermal stable and mechanical properties of the PUFs were investigated. The results of limiting oxygen index (LOI) and thermogravimetric analysis (TGA) revealed that PUFs filled with dimethyl methylphosphonate (DMMP) had better flame retardancy compared with other flame retardants and DMMP degraded at a low temperature to form several phosphorated acids which accelerated the formation of char layer. Composite flame retardant of DMMP and melamine (MA) had a synergistic effect between phosphorus and nitrogen. The combination of DMMP and MA slightly altered the density of the PUFs. Results from the mechanical analysis revealed that with the increase in concentration of MA in the composite flame retardant of DMMP and MA, the tensile strength of PUFs reduced firstly and then increased up to a constant.

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Synthesis of a Cyclophosphazene Derivative Containing Multiple Cyano Groups for Electron-Beam Irradiated Flame-Retardant Materials

Polymers ◽

10.3390/polym13203460 ◽

2021 ◽

Vol 13 (20) ◽

pp. 3460

Author(s):

Bingbing Leng ◽

Jiayu Yang ◽

Chunhui Zhu ◽

Zhipeng Wang ◽

Chengying Shi ◽

...

Keyword(s):

Electron Beam ◽

Flame Retardant ◽

Irradiation Dose ◽

Flame Retardants ◽

Maximum Tensile Stress ◽

High Energy ◽

Crosslinking Degree ◽

Limiting Oxygen Index ◽

Strict Requirement ◽

Cyano Groups

A cyclophosphazene derivative containing multiple cyano groups, denoted as hexa(4-cyanophenoxy)cyclotriphosphazene (CN-CP), was synthesized by a one-step nucleophilic substitution reaction for a phosphorus–nitrogen flame retardant. To meet the strict requirement of safe and environment-protective insulation materials, a series of composites based on low-density polyethylene-poly(ethylene-co-vinyl acetate) containing CN-CP/Mg(OH)2/Al(OH)3 organic-inorganic synergistic flame retardants was fabricated. High-energy electron beam irradiation was subsequently applied to obtain a halogen-free flame-retardant crosslinked system. The relationship between crosslinking degree and irradiation dose was studied, and crosslinking degrees ranging within 63–85% were obtained under 100–190 kGy. Furthermore, the effects of CN-CP filler and irradiation dose on the properties of the composites were carefully investigated. The maximum tensile stress and limiting oxygen index values of most composites irradiated by EB were more than 15 MPa and 28%. Results revealed that the obtained materials had excellent thermal and mechanical, flame-retardant, and insulation properties, thereby suggesting their promising prospects for wire and cable applications.

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