Mechanical and Flame Retardant Properties of Phenolic Foam Modified with Polyethyleneglycol as Toughening Agent

2013 ◽  
Vol 803 ◽  
pp. 21-25 ◽  
Author(s):  
Ming Gao ◽  
Yong Li Yang ◽  
Zhi Qiang Xu

Polyethyleneglycol (PEG) was used as a as a toughening agent and mixed with the phenolic resin to prepare the foam. The effects of polyethyleneglycol on mechanical and flame retardant properties of phenolic foam were studied by compressive strength, tensile strength, heat stability, scanning electron microscopy (SEM), UL-94 and limited oxygen index (LOI). The apparent density and SEM results showed that the addition of PEG can decrease the apparent density of phenolic foam. The compressive, impact test results showed that the incorporation of PEG into PF dramatically improved the compressive strength, impact strength, indicating the excellent toughening effect of PEG. The LOI of PEG modified phenolic foams remained a high value and the UL-94 results showed all samples can pass V-0 rating, indicating the modified foams still had good flame retardance. The thermal properties of the foams were investigated by thermogravimetric analysis.

2015 ◽  
Vol 18 (4) ◽  
pp. 16-22
Author(s):  
Linh Thi Thuy Pham ◽  
Hien Thi Thu Nguyen ◽  
Quy Thi Dong Hoang

In order to improve the fire performance of composite materials, halogen-free flame retardant (diamonium hydrogen phosphate- DAP) was studied in an attempt to obtain UL-94 ratings for composite PVC-wood flour (PVC-WF). The fire behaviors and thermal stability properties were evaluated using UL- 94 vertical test, LOI test and thermogravimetric analysis (TGA). The UL- 94 test results show that V-0 rating is achieved at 1.5 wt% of DAP loading. The incorporation of halogene-free flame retardant (FR) increases the flame retardant properties as well as the amounts of charred residues protecting the mixture from further degradation. This assertion can be accepted when observing that the char residual of PVC-WF/DAP mixture at 600 oC is much higher than that of neat PVC-WF. The char layer may limit the amount of fuel available and insulate the underlying composite material from the flame and, thus, inhibit further degradation. This FR is a promising candidate that could replace the halogenbased flame retardant.


Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3656
Author(s):  
Hangfeng Yang ◽  
Hangbo Yue ◽  
Xi Zhao ◽  
Minzimo Song ◽  
Jianwei Guo ◽  
...  

A novel halogen-free flame retardant containing sulfonamide, 1,3,5,7-tetrakis (phenyl-4-sulfonamide) adamantane (FRSN) was synthesized and used for improving the flame retardancy of largely used polycarbonate (PC). The flame-retardant properties of the composites with incorporation of varied amounts of FRSN were analyzed by techniques including limited oxygen index, UL 94 vertical burning, and cone calorimeter tests. The new FR system with sulfur and nitrogen elements showed effective improvements in PC’s flame retardancy: the LOI value of the modified PC increased significantly, smoke emission suppressed, and UL 94 V-0 achieved. Typically, the composite with only 0.08 wt% of FRSN added (an ultralow content) can increase the limiting oxygen index (LOI) value to 33.7% and classified as UL 94 V-0 rating. Furthermore, the mechanical properties and SEM morphology indicated that the FRSN has very good compatibility with PC matrix, which, in turn, is beneficial to the property enhancement. Finally, the analysis of sample residues after burning tests showed that a high portion of char was formed, contributing to the PC burning protection. This synthesized flame retardant provides a new way of improving PC’s flame retardancy and its mechanical property.


2013 ◽  
Vol 668 ◽  
pp. 53-56
Author(s):  
Gou Sheng Liu ◽  
Yue Long Liu

Ammonium polyphosphate (APP) produced by non-P2O5 process and traditional P2O5 process were used in the intumescent flame retardant (IFR) polypropylene (PP) composite (IFR-PP). The composite was tested by limited oxygen index (LOI) and UL-94. TGA and SEM were used to study the decomposition processes. Results showed that when the ratio of APP-II/ pentaerythritol/melamine is 3/1/1, the LOI value is 33.1, and all composite could reach UL-94 V0 rating. The results showed that APP by non-P2O5 process had similar IFR properties as APP of traditional P2O5 process


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.


Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1816 ◽  
Author(s):  
Marcin Borowicz ◽  
Joanna Paciorek-Sadowska ◽  
Jacek Lubczak ◽  
Bogusław Czupryński

This article raised the issue of studies on the use of new bio-polyol based on white mustard seed oil and 2,2’-thiodiethanol (3-thiapentane-1,5-diol) for the synthesis of rigid polyurethane/polyisocyanurate (RPU/PIR) foams. For this purpose, new formulations of polyurethane materials were prepared. Formulations contained bio-polyol content from 0 to 0.4 chemical equivalents of hydroxyl groups. An industrial flame retardant, tri(2-chloro-1-methylethyl) phosphate (Antiblaze TCMP), was added to half of the formulations. Basic foaming process parameters and functional properties, such as apparent density, compressive strength, brittleness, absorbability and water absorption, aging resistance, thermal conductivity coefficient λ, structure of materials, and flammability were examined. The susceptibility of the foams to biodegradation in soil was also examined. The increase in the bio-polyol content caused a slight increase in processing times. Also, it was noted that the use of bio-polyol had a positive effect on the functional properties of obtained RPU/PIR foams. Foams modified by bio-polyol based on mustard seed oil showed lower apparent density, brittleness, compressive strength, and absorbability and water absorption, as well as thermal conductivity, compared to the reference (unmodified) foams. Furthermore, the obtained materials were more resistant to aging and more susceptible to biodegradation.


2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Shibin Nie ◽  
Chi Zhang ◽  
Chao Peng ◽  
De-yi Wang ◽  
Daowei Ding ◽  
...  

A char forming agent (CFA) and silica-gel microencapsulated ammonium polyphosphate (Si-MCAPP) were selected to form novel intumescent flame retardant system to prepare flame retardant polypropylene (PP) composites, and then the influences of nanoporous nickel phosphates (NiP) on the thermal and flame retardant properties of flame retardant PP composites were studied by the real time FTIR (RTFTIR) spectra, limited oxygen index (LOI) test, and the scanning electron microscopy. RTFTIR shows the addition of NiP can improve the thermal stability of flame retardant PP composites. LOI test shows LOI value is increased with the increase of the content of NiP, and the optimized concentration of NiP is 1.0%. Furthermore, smoke toxicity of the novel flame retardant PP composites was studied by mice experiment. The upper limit of the no death smoke concentration of the composite is 12.37 mg/L.


2013 ◽  
Vol 749 ◽  
pp. 65-70
Author(s):  
Xiao Yan Li ◽  
Yan Chun Li ◽  
Chen Jie Shi ◽  
Si Si Cai ◽  
Xia Wang ◽  
...  

A kind of intumescent flame retardant (IFR) were used for flame retarding of oil-extended hydrogenated styrene-butylenes-styrene (O-SEBS). The samples were systemically characterized by limited oxygen index (LOI), vertical burning test (UL-94), and scanning electron microscopy (SEM); Thermogravimetric (TG) analysis. The results showed that the IFR retardant can promote residual chars with multi-micro holes on the surface of SEBS to inhibit flame; with 45% IFR content, the LOI is 28.3 and flame retardant level is UL-94 classification of V-0, with no dripping. The morphological structures observed by SEM demonstrated that higher IFR content promote to form larger and compact films cover on bubbles of the intumescent char layer. The TG data revealed that the IFR could change the degradation behavior of the O-SEBS, enhance the thermal stability and increase the char residue, The tensile strength of all the O-SEBS/IFR blends had the tensile strength of more than 4MPa and the elongation of more than 850%.


2017 ◽  
Vol 44 (1) ◽  
pp. 1-8
Author(s):  
K. Lehmann ◽  
A. Nawracala

The following article discusses the use of novel compounds from the Tegosil series which are intended to significantly increase the thermal conductivity of HCR- and even LSR-based silicone elastomers or to provide a simple way of improving their flame retardant properties by adding these compounds. Heat transfer characteristics from hot disc testing are presented and the reduced burn time in the UL 94 test demonstrates the improved flame resistance of the resulting elastomer formulations.


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