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Cherednichenko K, Smirnov E, Rubtsova M, Repin D, Semenov A. New Fire-Retardant Open-Cell Composite Polyurethane Foams Based on Triphenyl Phosphate and Natural Nanoscale Additives. Polymers (Basel) 2024; 16:1741. [PMID: 38932089 PMCID: PMC11207528 DOI: 10.3390/polym16121741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 05/29/2024] [Accepted: 06/14/2024] [Indexed: 06/28/2024] Open
Abstract
Despite the mechanical and physical properties of polyurethane foams (PUF), their application is still hindered by high inflammability. The elaboration of effective, low-cost, and environmentally friendly fire retardants remains a pressing issue that must be addressed. This work aims to show the feasibility of the successful application of natural nanomaterials, such as halloysite nanotubes and nanocellulose, as promising additives to the commercial halogen-free, fire-retardant triphenyl phosphate (TPP) to enhance the flame retardance of open-cell polyurethane foams. The nanocomposite foams were synthesized by in situ polymerization. Investigation of the mechanical properties of the nanocomposite PUF revealed that the nanoscale additives led to a notable decrease in the foam's compressibility. The obtained results of the flammability tests clearly indicate that there is a prominent synergetic effect between the fire-retardant and the natural nanoscale additives. The nanocomposite foams containing a mixture of TPP (10 and 20 parts per hundred polyol by weight) and either 10 wt.% of nanocellulose or 20 wt.% of halloysite demonstrated the lowest burning rate without dripping and were rated as HB materials according to UL 94 classification.
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Affiliation(s)
| | | | | | | | - Anton Semenov
- Department of Physical and Colloid Chemistry, National University of Oil and Gas «Gubkin University», 65 Leninsky Prospekt, Moscow 119991, Russia; (K.C.); (E.S.); (M.R.); (D.R.)
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2
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Cheng HL, Chu N, Jin FL, Park SJ. Role of Copper Nanoparticles in the Thermal and Mechanical Properties of Expanded Graphite-Reinforced Epoxy Hybrids. ACS OMEGA 2024; 9:17533-17540. [PMID: 38645326 PMCID: PMC11025089 DOI: 10.1021/acsomega.4c00394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 03/08/2024] [Accepted: 03/19/2024] [Indexed: 04/23/2024]
Abstract
Epoxy resin is extensively applied in the electronics and electrical fields because of its outstanding comprehensive performance. However, the low thermal conductivity (TC) limits its application in thermal interface materials. In the present work, epoxy-based hybrid composites with high TC were prepared by using expanded graphite (EG) and copper (Cu) nanoparticles as thermally conductive hybrid fillers via hot blending and compression-curing processes. Additionally, the influence of the Cu content on the thermal properties, mechanical properties, and morphology of each epoxy/EG/Cu composite was investigated. According to the results, the epoxy/EG/Cu composite showed a maximum TC of 9.74 W/(m·K) at a fixed EG content of 60 wt % owing to the addition of 10 wt % Cu. After the addition of 10 wt % Cu, the flexural strength, flexural modulus, and impact strengths of epoxy/EG/Cu composites were improved from 27.9 MPa, 9.72 GPa, and 0.81 kJ/m2 to 37.5 MPa, 10.88 GPa, and 0.91 kJ/m2, respectively. Hence, this study offers a feasible strategy for the design of epoxy hybrid composites with excellent TC that can be applied to thermal interface materials.
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Affiliation(s)
- Hai-Long Cheng
- Department
of Polymer Materials, Jilin Institute of
Chemical Technology, Jilin 132022, People’s
Republic of China
| | - Na Chu
- Department
of Polymer Materials, Jilin Institute of
Chemical Technology, Jilin 132022, People’s
Republic of China
| | - Fan-Long Jin
- Department
of Polymer Materials, Jilin Institute of
Chemical Technology, Jilin 132022, People’s
Republic of China
| | - Soo-Jin Park
- Department
of Chemistry, Inha University, Michuhol-gu, Incheon 22212, South Korea
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Kabir II, Carlos Baena J, Wang W, Wang C, Oliver S, Nazir MT, Khalid A, Fu Y, Yuen ACY, Yeoh GH. Optimisation of Additives to Maximise Performance of Expandable Graphite-Based Intumescent-Flame-Retardant Polyurethane Composites. Molecules 2023; 28:5100. [PMID: 37446760 DOI: 10.3390/molecules28135100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/20/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
The effect of varying the weight percentage composition (wt.%) of low-cost expandable graphite (EG), ammonium polyphosphate (APP), fibreglass (FG), and vermiculite (VMT) in polyurethane (PU) polymer was studied using a traditional intumescent flame retardant (IFR) system. The synergistic effect between EG, APP, FG, and VMT on the flame retardant properties of the PU composites was investigated using SEM, TGA, tensile strength tests, and cone calorimetry. The IFR that contained PU composites with 40 wt.% EG displayed superior flame retardant performance compared with the composites containing only 20 w.t.% or 10 w.t.% EG. The peak heat release rate, total smoke release, and carbon dioxide production from the 40 wt.% EG sample along with APP, FG, and VMT in the PU composite were 88%, 93%, and 92% less than the PU control sample, respectively. As a result, the synergistic effect was greatly influenced by the compactness of the united protective layer. The PU composite suppressed smoke emission and inhibited air penetrating the composite, thus reducing reactions with the gas volatiles of the material. SEM images and TGA results provided positive evidence for the combustion tests. Further, the mechanical properties of PU composites were also investigated. As expected, compared with control PU, the addition of flame-retardant additives decreased the tensile strength, but this was ameliorated with the addition of FG. These new PU composite materials provide a promising strategy for producing polymer composites with flame retardation and smoke suppression for construction materials.
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Affiliation(s)
- Imrana I Kabir
- School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Juan Carlos Baena
- School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Wei Wang
- School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Cheng Wang
- School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Susan Oliver
- School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Muhammad Tariq Nazir
- Electrical and Biomedical Engineering, School of Engineering, RMIT University, Melbourne, VIC 3001, Australia
| | - Arslan Khalid
- School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Yifeng Fu
- School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Anthony Chun Yin Yuen
- School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia
- Department of Building Environment and Energy Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Guan Heng Yeoh
- School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, NSW 2052, Australia
- Australian Nuclear Science and Technology Organisation (ANSTO), Locked Bag 2001, Kirrawee DC, NSW 2232, Australia
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Cherednichenko K, Kopitsyn D, Smirnov E, Nikolaev N, Fakhrullin R. Fireproof Nanocomposite Polyurethane Foams: A Review. Polymers (Basel) 2023; 15:polym15102314. [PMID: 37242889 DOI: 10.3390/polym15102314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/08/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023] Open
Abstract
First introduced in 1954, polyurethane foams rapidly became popular because of light weight, high chemical stability, and outstanding sound and thermal insulation properties. Currently, polyurethane foam is widely applied in industrial and household products. Despite tremendous progress in the development of various formulations of versatile foams, their use is hindered due to high flammability. Fire retardant additives can be introduced into polyurethane foams to enhance their fireproof properties. Nanoscale materials employed as fire-retardant components of polyurethane foams have the potential to overcome this problem. Here, we review the recent (last 5 years) progress that has been made in polyurethane foam modification using nanomaterials to enhance its flame retardance. Different groups of nanomaterials and approaches for incorporating them into foam structures are covered. Special attention is given to the synergetic effects of nanomaterials with other flame-retardant additives.
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Affiliation(s)
- Kirill Cherednichenko
- Department of Physical and Colloid Chemistry, Faculty of Chemical and Environmental Engineering, National University of Oil and Gas "Gubkin University", Moscow 119991, Russia
| | - Dmitry Kopitsyn
- Department of Physical and Colloid Chemistry, Faculty of Chemical and Environmental Engineering, National University of Oil and Gas "Gubkin University", Moscow 119991, Russia
| | - Egor Smirnov
- Department of Physical and Colloid Chemistry, Faculty of Chemical and Environmental Engineering, National University of Oil and Gas "Gubkin University", Moscow 119991, Russia
| | - Nikita Nikolaev
- Department of Physical and Colloid Chemistry, Faculty of Chemical and Environmental Engineering, National University of Oil and Gas "Gubkin University", Moscow 119991, Russia
| | - Rawil Fakhrullin
- Department of Physical and Colloid Chemistry, Faculty of Chemical and Environmental Engineering, National University of Oil and Gas "Gubkin University", Moscow 119991, Russia
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kreml Uramı 18, Kazan 420008, Russia
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Wang H, Liu Q, Li H, Zhang H, Yan S. Flame-Retardant and Smoke-Suppressant Flexible Polyurethane Foams Based on Phosphorus-Containing Polyester Diols and Expandable Graphite. Polymers (Basel) 2023; 15:polym15051284. [PMID: 36904525 PMCID: PMC10006967 DOI: 10.3390/polym15051284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/27/2023] [Accepted: 02/01/2023] [Indexed: 03/06/2023] Open
Abstract
A liquid-phosphorus-containing polyester diol, PPE, was prepared via condensation polymerization using commercial reactive flame retardant 9,10-dihydro-10-[2,3-di(hydroxycarbonyl)propyl]-10-phospha-phenanthrene-10-oxide, adipic acid, ethylene glycol, and 1,4-butanediol. PPE and/or expandable graphite (EG) were then incorporated into phosphorus-containing flame-retardant polyester-based flexible polyurethane foams (P-FPUFs). The structure and properties of the resultant P-FPUFs were characterized using scanning electron microscopy tensile measurements, limiting oxygen index (LOI), vertical burning tests, cone calorimeter tests, thermogravimetric analysis coupled with Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. Unlike the FPUF prepared using regular polyester polyol (R-FPUF), PPE increased the flexibility and elongation at break of the resultant forms. More importantly, the peak heat release rate (PHRR) and total heat release (THR) of P-FPUF were reduced by 18.6% and 16.3%, respectively, via gas-phase-dominated flame-retardant mechanisms, compared with those of R-FPUF. The addition of EG further reduced the peak smoke production release (PSR) and total smoke production (TSP) of the resultant FPUFs while increasing the LOI and char formation. Interestingly, it was observed that EG noticeably improved the residual quantity of phosphorus in the char residue. When the EG loading was 15 phr, the resulting FPUF (P-FPUF/15EG) attained a high LOI value (29.2%) and exhibited good anti-dripping performance. Meanwhile, the PHRR, THR, and TSP of P-FPUF/15EG were significantly decreased by 82.7%, 40.3%, and 83.4%, respectively, compared with those of P-FPUF. This superior flame-retardant performance can be attributed to the combination of the bi-phase flame-retardant behavior of PPE and condensed-phase flame-retardant characteristics of EG.
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Affiliation(s)
| | - Qiang Liu
- Correspondence: (Q.L.); (H.L.); (S.Y.)
| | - Hui Li
- Correspondence: (Q.L.); (H.L.); (S.Y.)
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On-Line Thermally Induced Evolved Gas Analysis: An Update-Part 2: EGA-FTIR. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27248926. [PMID: 36558054 PMCID: PMC9788466 DOI: 10.3390/molecules27248926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 12/11/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022]
Abstract
The on-line thermally induced evolved gas analysis (OLTI-EGA) is widely applied in many different fields. Aimed to update the applications, our group has systematically collected and published examples of EGA characterizations. Following the recently published review on EGA-MS applications, this second part reviews the latest applications of Evolved Gas Analysis performed by on-line coupling heating devices to infrared spectrometers (EGA-FTIR). The selected 2019, 2020, 2021 and early 2022 references are collected and briefly described in this review; these are useful to help researchers to easily find applications that are sometimes difficult to locate.
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Lee SH, Lee SG, Lee JS, Ma BC. Understanding the Flame Retardant Mechanism of Intumescent Flame Retardant on Improving the Fire Safety of Rigid Polyurethane Foam. Polymers (Basel) 2022; 14:polym14224904. [PMID: 36433031 PMCID: PMC9696838 DOI: 10.3390/polym14224904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/07/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022] Open
Abstract
Combinations of multiple inorganic fillers have emerged as viable synergistic agents for boosting the flame retardancy of intumescent flame retardant (IFR) polymer materials. However, few studies on the effect of multiple inorganic fillers on the flame retardant behavior of rigid polyurethane (RPU) foam have been carried out. In this paper, a flame retardant combination of aluminum hydroxide (ATH) and traditional flame retardants ammonium polyphosphate (APP), pentaerythritol (PER), melamine cyanurate (MC), calcium carbonate (CC), and expandable graphite (EG) was incorporated into RPU foam to investigate the synergistic effects of the combination of multiple IFR materials on the thermal stability and fire resistance of RPU foam. Scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) revealed that 8 parts per hundred polyols by weight (php) filler concentrations were compatible with RPU foam and yielded an increased amount of char residue compared to the rest of the RPU samples. The flame retardancy of multiple fillers on intumescent flame retardant RPU foam was also investigated using cone calorimeter (CCTs) and limiting oxygen index (LOI) tests, which showed that RPU/IFR1 (APP/PER/MC/EG/CC/ATH) had the best flame retardant performance, with a low peak heat release rate (PHRR) of 82.12 kW/m2, total heat release rate (THR) of 15.15 MJ/m2, and high LOI value of 36%. Furthermore, char residue analysis revealed that the use of multiple fillers contributed to the generation of more intact and homogeneous char after combustion, which led to reduced decomposition of the RPU foam and hindered heat transfer between the gas and condensed phases.
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8
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Yang R, Gu G, Li M, Li J. Preparation of flame‐retardant rigid polyurethane foam with bio‐based phosphorus‐containing polyols and expandable graphite. J Appl Polym Sci 2022. [DOI: 10.1002/app.53167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Rong Yang
- Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering Changzhou University Changzhou China
| | - Guozhang Gu
- Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering Changzhou University Changzhou China
| | - Mengdi Li
- Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering Changzhou University Changzhou China
| | - Jinchun Li
- Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering Changzhou University Changzhou China
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9
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Gao Q, Zhao H, Zhou XL, Liu FY, Jiao YH, Xie JX, Qu HQ, Xu JZ, Ma HY. Flame retardant, combustion and thermal degradation properties of polypropylene composites treated with the mixture of pentaerythritol, nickel hydroxystannate and expandable graphite. Polym Degrad Stab 2022. [DOI: 10.1016/j.polymdegradstab.2022.110084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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10
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Qiu Y, Xi B, Qian L, Liu A, Gao L. Carbonization‐dominated synergistic behaviors of ammonium hypophosphite/
EG
composite in improving flame retardancy of flexible polyurethane foam. POLYM ADVAN TECHNOL 2022. [DOI: 10.1002/pat.5775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yong Qiu
- College of Chemistry and Materials Engineering Beijing Technology and Business University Beijing China
- China Light Industry Engineering Technology Research Center of Advanced Flame Retardants Beijing Technology and Business University Beijing China
- Petroleum and Chemical Industry Engineering Laboratory of Non‐halogen Flame Retardants for Polymers Beijing Technology and Business University Beijing China
| | - Baoan Xi
- College of Chemistry and Materials Engineering Beijing Technology and Business University Beijing China
- China Light Industry Engineering Technology Research Center of Advanced Flame Retardants Beijing Technology and Business University Beijing China
- Petroleum and Chemical Industry Engineering Laboratory of Non‐halogen Flame Retardants for Polymers Beijing Technology and Business University Beijing China
| | - Lijun Qian
- College of Chemistry and Materials Engineering Beijing Technology and Business University Beijing China
- China Light Industry Engineering Technology Research Center of Advanced Flame Retardants Beijing Technology and Business University Beijing China
- Petroleum and Chemical Industry Engineering Laboratory of Non‐halogen Flame Retardants for Polymers Beijing Technology and Business University Beijing China
| | - Anqi Liu
- College of Chemistry and Materials Engineering Beijing Technology and Business University Beijing China
- China Light Industry Engineering Technology Research Center of Advanced Flame Retardants Beijing Technology and Business University Beijing China
- Petroleum and Chemical Industry Engineering Laboratory of Non‐halogen Flame Retardants for Polymers Beijing Technology and Business University Beijing China
| | - Lun‐Bagen Gao
- College of Chemistry and Materials Engineering Beijing Technology and Business University Beijing China
- China Light Industry Engineering Technology Research Center of Advanced Flame Retardants Beijing Technology and Business University Beijing China
- Petroleum and Chemical Industry Engineering Laboratory of Non‐halogen Flame Retardants for Polymers Beijing Technology and Business University Beijing China
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Chan YY, Schartel B. It Takes Two to Tango: Synergistic Expandable Graphite–Phosphorus Flame Retardant Combinations in Polyurethane Foams. Polymers (Basel) 2022; 14:polym14132562. [PMID: 35808608 PMCID: PMC9269610 DOI: 10.3390/polym14132562] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/20/2022] [Accepted: 06/21/2022] [Indexed: 12/20/2022] Open
Abstract
Due to the high flammability and smoke toxicity of polyurethane foams (PUFs) during burning, distinct efficient combinations of flame retardants are demanded to improve the fire safety of PUFs in practical applications. This feature article focuses on one of the most impressive halogen-free combinations in PUFs: expandable graphite (EG) and phosphorus-based flame retardants (P-FRs). The synergistic effect of EG and P-FRs mainly superimposes the two modes of action, charring and maintaining a thermally insulating residue morphology, to bring effective flame retardancy to PUFs. Specific interactions between EG and P-FRs, including the agglutination of the fire residue consisting of expanded-graphite worms, yields an outstanding synergistic effect, making this approach the latest champion to fulfill the demanding requirements for flame-retarded PUFs. Current and future topics such as the increasing use of renewable feedstock are also discussed in this article.
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Pang X, Zhang W, Meng Y, Ma M, Xu J. Effect of expansion temperature on the properties of expanded graphite and modified linear low density polyethylene. INT POLYM PROC 2022. [DOI: 10.1515/ipp-2022-0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
To study the influence of expansion temperature on the properties of expanded graphite (EBG), EBG300, EBG600, and EBG900 were prepared by heating expandable graphite (EG) at 300, 600, and 900 °C, respectively. Furthermore, the influence of these EBGs on the combustion performance and physical-mechanical properties of linear low density polyethylene (LLDPE) were investigated. The expansion volumes of EBG300, EBG600, and EBG900 increase with the rise of temperature, and a four-stage ordered structure of “graphite worm” gradually forms. The thermal stability increases gradually for EBG300, EBG600, and EBG900. On the contrary, the thermal conductivity decreases in sequence. However, the incorporation of EBG900 promotes the formation of a continuous network structure and makes the modified LLDPE to present the best heat transmission. The addition of 30 wt% of these EBGs significantly improves LLDPE’s flame retardancy and high-temperature thermal stability. The total heat release, the peak value of heat release rate, and the fire growth index of 70LLDPE/30EBG300 reduce by 69, 91, and 87% respectively, while the effective fire performance index improves seven times. The addition of these additives reduces the tensile strength and elongation at break, the larger the EBG size, the more obvious the effect.
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Affiliation(s)
- Xiuyan Pang
- College of Chemistry and Environmental Science , Hebei University , Wusi East Road No. 180 , Baoding , 071002 , P. R. China
- Flame Retardant Material and Processing Technology Engineering Technology Research Center of Hebei Province; Key Laboratory of Analytical Science and Technology of Hebei Province , Hebei University , Baoding , P. R. China
| | - Wenyu Zhang
- College of Chemistry and Environmental Science , Hebei University , Wusi East Road No. 180 , Baoding , 071002 , P. R. China
| | - Yafang Meng
- College of Chemistry and Environmental Science , Hebei University , Wusi East Road No. 180 , Baoding , 071002 , P. R. China
| | - Meifang Ma
- College of Chemistry and Environmental Science , Hebei University , Wusi East Road No. 180 , Baoding , 071002 , P. R. China
| | - Jianzhong Xu
- College of Chemistry and Environmental Science , Hebei University , Wusi East Road No. 180 , Baoding , 071002 , P. R. China
- Flame Retardant Material and Processing Technology Engineering Technology Research Center of Hebei Province; Key Laboratory of Analytical Science and Technology of Hebei Province , Hebei University , Baoding , P. R. China
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