scholarly journals FLAME RETARDATION PERFORMANCES OF HALOGEN-FREE FLAME RETARDANT WHEN APPLIED TO UNSATURATED POLYESTER

2012 ◽  
Vol 15 (3) ◽  
pp. 73-79
Author(s):  
Quy Thi Dong Hoang ◽  
Cuong Ngoc Hoang ◽  
Anh Huynh Tram Pham ◽  
Vien Tri Thiem ◽  
Huong Ngoc Nhu Nguyen ◽  
...  

In order to improve fire performance of polymeric materials, phosphorus flame retardants (FRs) were studied in an attempt to obtain UL-94 ratings for materials based on unsaturated polyester. The fire behaviors and thermal stability properties were evaluated using UL-94 vertical test and thermogravimetric analysis (TGA). The UL-94 test results show that V-1 rating is achieved. TGA and UL-94 results concluded that phosphorus FRs employed in this study works on both vapor phase and condensed phase, but the vapour phase is dominant mode of action. These suggested that the addition of FRs probably does affect on the char layer formed during combustion behavior and increase the flame retardant properties in the case of condensed phase mode of action. The efficiency of flame retardant of phosphorus also highly depends upon the phosphorus moieties generated during the decomposition which further converted to radical capturing species, and consequently quenching the flame in the case of gas phase mode of action. These FRs can be promising candidates that replace the halogen-based.

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3496
Author(s):  
Junming Geng ◽  
Jianyu Qin ◽  
Jiyu He

An intercalated organic montmorillonite DOPO-MMT was prepared through the melting method using 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) as a modifier. Epoxy resin (EP) composites were prepared with DOPO-MMT, DOPO, MMT, and the physical mixtures of DOPO+MMT as flame retardants. The microstructure of the flame retardants and EP samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The flame retardant properties, thermal stability, and residual char structure of the EPs were studied by the limited oxygen index (LOI) test, the UL-94 vertical burning test, thermogravimetric analysis (TGA), the differential scanning calorimeter (DSC) test, the cone calorimeter (CONE) test as well as other characterization methods. The results showed that the intercalated organic montmorillonite DOPO-MMT can be successfully prepared by the melting method and that the MMT is evenly dispersed in the EP/DOPO-MMT composite in the form of nanosheets. The EP/DOPO-MMT nanocomposites showed the optimal flame retardancy (LOI, UL-94, PHRR, etc.) among the EPs with DOPO, MMT, and the physical mixture of DOPO+MMT. The flame-retardant grade of the material reached V-0.


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
F. I. Beltrán-Ramírez ◽  
L. F. Ramos-deValle ◽  
E. Ramírez-Vargas ◽  
S. Sánchez-Valdes ◽  
A. B. Espinoza-Martínez ◽  
...  

The effect of nanometric magnesium and aluminum hydroxides on the flame retardancy of high density polyethylene was studied. Additionally, the effect of maleic anhydride grafted polyethylene (PEgMA) and methyl acrylate grafted polyethylene (EMA) compatibilizers, on the tensile properties, was also studied. Morphological characterization of nanocomposites was carried out by means of scanning transmission electron microscopy (STEM). Flame retardant properties of nanocomposites were evaluated by the UL-94 horizontal and vertical tests as well as by cone calorimeter tests. Thermal degradation behavior was analyzed with a thermogravimetric analyzer (TGA). Tensile tests were carried out according to ASTM D 638-03 in an Instron 4301 tensile testing machine. From STEM images, a good dispersion of flame retardants (MH and ATH) in the polymer matrix was observed, which was reflected in the flame retardant properties. Results showed that the combination of nanometric MH and ATH produced excellent flame retardant properties, achieving a classification of V0 in the UL-94-V test and producing the lowest peak of heat release rate (PHRR) and the lowest total heat released (THR) in the cone calorimeter test. Finally, the addition of compatibilizer, especially PEgMA, resulted in much better tensile properties as compared to the noncompatibilized composition, maintaining the flame retardant properties.


Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1181
Author(s):  
Noha Ramadan ◽  
Mohamed Taha ◽  
Angela Daniela La Rosa ◽  
Ahmed Elsabbagh

Epoxy and unsaturated polyester resins are the most used thermosetting polymers. They are commonly used in electronics, construction, marine, automotive and aircraft industries. Moreover, reinforcing both epoxy and unsaturated polyester resins with carbon or glass fibre in a fabric form has enabled them to be used in high-performance applications. However, their organic nature as any other polymeric materials made them highly flammable materials. Enhancing the flame retardancy performance of thermosetting polymers and their composites can be improved by the addition of flame-retardant materials, but this comes at the expense of their mechanical properties. In this regard, a comprehensive review on the recent research articles that studied the flame retardancy of epoxy resin, unsaturated polyester resin and their composites were covered. Flame retardancy performance of different flame retardant/polymer systems was evaluated in terms of Flame Retardancy index (FRI) that was calculated based on the data extracted from the cone calorimeter test. Furthermore, flame retardant selection charts that relate between the flame retardancy level with mechanical properties in the aspects of tensile and flexural strength were presented. This review paper is also dedicated to providing the reader with a brief overview on the combustion mechanism of polymeric materials, their flammability behaviour and the commonly used flammability testing techniques and the mechanism of action of flame retardants.


2015 ◽  
Vol 44 (2) ◽  
pp. 101-108 ◽  
Author(s):  
H. Abd El-Wahab

Purpose – This paper aims to report on the synthesis and characterisation of new flame retardants and anticorrosive additives based on Schiff’s base compounds, which were added physically to organic coating. Design/methodology/approach – Flame retardants are incorporated into polymeric materials either as additives or as reactive materials. Additive-type flame retardants are widely used by incorporating into polymeric materials by physical means. In this research, Schiff’s base (azomethine) compounds are added physically to alkyd paint as flame-retardant additives. Elemental analysis, infrared spectroscopy and proton nuclear magnetic resonance spectroscopy were used to characterise the structure of the prepared Schiff’s base compounds. Thermal gravimetric analysis was used to evaluate their thermal stability. Experimental coatings were manufactured on a laboratory scale, and then applied by brush on wood and steel panels. Findings – Results of an oxygen index value indicated that alkyd paints containing Schiff’s base compounds as additives exhibit very good flame-retardant effects. Also the physical, mechanical and corrosion resistance properties were studied to evaluate the drawbacks of the additives. The additives did not affect the flexibility of the paint formula. The gloss and the impact strength were decreased by the additives, but the hardness, adhesion and corrosion resistance were significantly improved by these additives. Research limitations/implications – Alkyd resins are the most extensively used synthetic polymers in the coating industry. Nitrogen compounds are a small but rapidly growing group of flame retardants which are in the focus of public interest concerning environment-friendly flame retardants. So, the focus of this study is on Schiff’s base compounds as flame retardants and anticorrosive additives for alkyd resins to assess their applicability. Practical implications – Schiff’s base compounds can be used as new additives in paint formulations to improve the flame-retardant and corrosion properties. Originality/value – In recent years, there has been considerable interest in the nitrogen-based family of materials because they not only have a wide range of thermal and chemical stabilities, but can also provide improved thermal and flame-retardant properties to polymers. The present paper reports on the synthesis and characterisation of Schiff’s base compounds and their performance in alkyd resin coatings.


2009 ◽  
Vol 87-88 ◽  
pp. 427-432 ◽  
Author(s):  
Peng Ding ◽  
Sheng Fu Tang ◽  
Hui Yang ◽  
Li Yi Shi

The structure, thermal behavior and flame retardant properties of polypropylene (PP) nanocomposites treated with complex flame retardants composed of layered double hydroxides (LDH) and ammonium polyphosphate (APP)/pentaerythritol (PER) intumescent flame retardant systems have been investigated by XRD, TEM, LOI, UL-94, and TGA analysis. The results showed that introduction of LDH nanofillers into the samples can obtain good flame retardant synergistic effects with APP/PER additives at appropriate LDH loadings. Such synergism between LDH and APP/PER in PP matrix can be explained by a proposed condensed phase flame retardant mechanism. And based on this study, different types of modified PP products were developed in a ten-thousand-ton scale to be used for the automobile industries, such as car bumpers and dashboards.


Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 540
Author(s):  
Yukyung Kim ◽  
Sanghyuck Lee ◽  
Hyeonseok Yoon

Currently, polymers are competing with metals and ceramics to realize various material characteristics, including mechanical and electrical properties. However, most polymers consist of organic matter, making them vulnerable to flames and high-temperature conditions. In addition, the combustion of polymers consisting of different types of organic matter results in various gaseous hazards. Therefore, to minimize the fire damage, there has been a significant demand for developing polymers that are fire resistant or flame retardant. From this viewpoint, it is crucial to design and synthesize thermally stable polymers that are less likely to decompose into combustible gaseous species under high-temperature conditions. Flame retardants can also be introduced to further reinforce the fire performance of polymers. In this review, the combustion process of organic matter, types of flame retardants, and common flammability testing methods are reviewed. Furthermore, the latest research trends in the use of versatile nanofillers to enhance the fire performance of polymeric materials are discussed with an emphasis on their underlying action, advantages, and disadvantages.


2019 ◽  
Vol 37 (2) ◽  
pp. 137-154 ◽  
Author(s):  
Xi Cheng ◽  
Jianming Wu ◽  
Yulin Li ◽  
Chenguang Yao ◽  
Guisheng Yang

Aluminum hypophosphite combined with melamine cyanurate and poly(phenylene oxide) was applied to flame-retard TPE-S system (blends of SEBS and polyolefin). The flame-retardant properties of the TPE-S/AHP/MCA/PPO were investigated by LOI and vertical burning test (UL-94). The results indicated that TPE-S containing 16 wt% AHP, 20 wt% MCA, and 10 wt% PPO reached a V-0 rating in the UL-94 test, and its LOI value was 28.2%. It performed well in the cone calorimeter (reduction in peak heat release rate from 2001 to 494 kW m−2). Thermogravimetric-Fourier transform infrared spectroscopy tests showed that AHP and MCA acted in gaseous phase, while AHP and PPO helped to form char residue. The SEM graphs demonstrated that continuous and compact films cover bubbles of the char layer in TPE-S/AHP/MCA/PPO. The proposed flame-retardant mechanisms of such systems were summarized.


2011 ◽  
Vol 197-198 ◽  
pp. 1346-1349 ◽  
Author(s):  
Fa Chao Wu

Bis(2,6,7-trioxa-l-phosphabicyclo[2.2.2]octane-4-methanol) melaminium salt (Melabis) and microcapsules of Melabis with melamine resin shell as flame retardants (FR), respectively, were synthesized. Their structures were characterized by NMR, IR, SEM, TG and element analysis. 20% weight of microcapsules was doped into epoxy resins (EP) to get 28.5 % of LOI and UL 94 V-0. The heat and smoke release of EP containing microcapsules was valued by cone calorimeter.


2011 ◽  
Vol 236-238 ◽  
pp. 1152-1155
Author(s):  
Lei Gao ◽  
Bo Wen Cheng ◽  
Jun Song ◽  
Zeng Geng Guo ◽  
Fei Lu ◽  
...  

This paper has studied the structure and flame-retardant properties of flame-retardant cellulose fiber with DDPSN as flame retardant. The flame retardants was uniformly dispersed in the cellulose /[Amim]Cl Solution to obtain the good spinnable dope, then the dope was wet-spun. Effects of the flame-retardant contention the fiber structure and properties were investigated. The surface of the flame-retardant cellulose fiber was observed using field emission scanning electron microscope (FESEM). Besides, through the Simultaneous thermal analysis, it has been shown that, with the increase of fame retardant, the degree of fame resistance was obviously improved. The flame retardant acted greatly in condensed phase during the fiber degradation and remained mainly in residues after degradation, the experiments show that the flame-retardant properties of flame-retardant cellulose fiber with 20wt% DDPSN was obvious.


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