scholarly journals Effect of Magnesium Hydroxide and Aluminum Hydroxide on the Thermal Stability, Latent Heat and Flammability Properties of Paraffin/HDPE Phase Change Blends

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 180 ◽  
Author(s):  
Ru Zhou ◽  
Zhuang Ming ◽  
Jiapeng He ◽  
Yanming Ding ◽  
Juncheng Jiang
Keyword(s):  
Thermal Stability ◽  
Phase Change ◽  
Heat Release ◽  
Flame Retardant ◽  
Latent Heat ◽  
Aluminum Hydroxide ◽  
Heat Release Rate ◽  
Magnesium Hydroxide ◽  
Release Rate ◽  
Gravimetric Analysis

In this study, paraffin was selected as the phase change material (PCM) and high-density polyethylene (HDPE) as the supporting material to prepare a flame-retardant PCM system. The system consisted of paraffin, HDPE, expanded graphite (EG), magnesium hydroxide (MH) and aluminum hydroxide (ATH). The thermal stability and flame retardancy were studied by thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM) and cone calorimeter test (CONE). The SEM proved that the addition of MH and ATH can produce an oxide film on the surface of the composite material and form a “physical barrier” with the char layer, generated by the expansion of EG, preventing the transfer of heat and oxygen. The TGA test showed that, compared with other flame-retardant systems, the materials with added MH and ATH have a higher thermal stability and carbonization ability, and the amount of char residue has increased from 17.6% to 32.9%, which reduces the fire risk of the material. The flame retardant effect is obvious. In addition, the addition of MH and ATH has no significant effect on the phase transition temperature and latent heat value of PCMs. The CONE data further confirmed that MH and ATH can work with EG to prevent heat release, reduce the total heat release rate (THR) value and effectively suppress the generation of smoke, CO and CO2. The peak heat release rate (PHRR) value also decreased, from 1570.2 kW/m2 to 655.9 kW/m2.

Synthesis of Novel Alkyl Phosphinate Double Salt and its Application in PA6

2014 ◽  
Vol 997 ◽  
pp. 89-92
Author(s):  
Jia Chen ◽  
Yuan Fang Zhang ◽  
Da Jiang Du ◽  
Ji Yan Liu
Keyword(s):  
Thermal Stability ◽  
Heat Release ◽  
Flame Retardant ◽  
Heat Release Rate ◽  
Release Rate ◽  
Filler Loading ◽  
Double Salt ◽  
Strong Inhibition ◽  
Excellent Thermal Stability ◽  
Inhibition Effect

In this paper, zinc magnesium methyl cyclohexylphosphinate double salt (ZnMg (MHP)) was synthesized and used as flame retardant for PA6. The structure and the flammability of ZnMg (MHP) had been studied. The results presented that the LOI of PA6 with 20wt% filler loading improved from 21.2% to 31.4%, and the vertical burning test passed UL94 V-0 rating. TG analyses showed that ZnMg (MHP) had excellent thermal stability. DSC displayed that ZnMg (MHP) melted at 235°C. The tests of flammability revealed that ZnMg (MHP) had a strong inhibition effect on heat release rate (HRR) of the composites.

scholarly journals Preparation of γ-Divinyl-3-Aminopropyltriethoxysilane Modified Lignin and Its Application in Flame Retardant Poly(lactic acid)

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1505 ◽  
Author(s):  
Yan Song ◽  
Xu Zong ◽  
Nan Wang ◽  
Ning Yan ◽  
Xueying Shan ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Lactic Acid ◽  
Heat Release ◽  
Flame Retardant ◽  
Heat Release Rate ◽  
Flame Retardancy ◽  
Release Rate ◽  
Poly Lactic Acid ◽  
Modified Lignin ◽  
Thermal Stability Of

Lignin can be a candidate as a charring agent applied in halogen-free flame retardant polymers, and incorporation of silicon and nitrogen elements in lignin can benefit to enhancing its thermal stability and charring ability. In the present work, wheat straw alkali lignin (Lig) was modified to incorporate silicon and nitrogen elements by γ-divinyl-3-aminopropyltriethoxysilane, and the modified lignin (CLig) was combined with ammonium polyphosphate (APP) as intumescent flame retardant to be applied in poly(Lactic acid) (PLA). The flame retardancy, combustion behavior and thermal stability of PLA composites were studied by the limited oxygen index (LOI), vertical burning testing (UL-94), cone calorimetry testing (CCT) and thermogravimetric analysis (TGA), respectively. The results showed a significant synergistic effect between CLig and APP in flame retarded PLA (PLA/APP/CLig) occured, and the PLA/APP/CLig had better flame retardancy. CCT data analysis revealed that CLig and APP largely reduced the peak heat release rate (PHRR) and total heat release rate (THR) of PLA, indicating their effectiveness in decreasing the combustion of PLA. TGA results exhibited that APP and CLig improved the thermal stability of PLA at high temperature. The analysis of morphology and structure of residual char indicated that a continuous, compact and intumescent char layer on the material surface formed during firing, and had higher graphitization degree. Mechanical properties data showed that PLA/APP/CLig had higher tensile strength as well as elongation at break.

Intumescent flame retardant coating for polyamide 6,6 (PA 6,6) fabrics containing carbon nanotubes: Synergistic effect of filler on thermal stability and flame retardancy

2018 ◽  
Vol 89 (10) ◽  
pp. 2031-2040 ◽  
Author(s):  
Fanglong Zhu ◽  
QQ Feng ◽  
YF Xu ◽  
JF Hu
Keyword(s):  
Carbon Nanotubes ◽  
Thermal Stability ◽  
Heat Release ◽  
Flame Retardant ◽  
Heat Release Rate ◽  
Flame Retardancy ◽  
Release Rate ◽  
Intumescent Flame Retardant ◽  
Flame Resistance ◽  
Limiting Oxygen Index

Flame retardant mixtures of multi-walled carbon nanotubes (MWCNTs) and intumescent flame retardant (IFR) coatings were applied to polyamide 6,6 (PA 6,6) fabrics to explore whether MWCNTs acted as a good synergist on the thermal stability and flame resistance of the IFR system. The influence of MWCNTs on the flame retardant properties and thermal degradation of the PA 6,6 fabrics were investigated by limiting oxygen index (LOI), vertical burning test (VBT), thermogravimetric analyzer (TGA), scanning electron microscopy (SEM) and cone calorimeter test (CCT). The peak heat release rate and total heat release of the IFR-PA 6,6 fabric with three kinds of wt% MWCNTs were lower than those of the only traditional IFR-PA 6,6 fabric (reduced by 74.2–76.4% and 74.3–76.5%, respectively). As compared to the traditional IFR coating, it was found that no enhancements for thermal stability and flame retardancy in terms of the ability to retard ignition were achieved for the MWCNT/IFR coating. These results demonstrated that the introduction of MWCNTs into an IFR coating can improve the flame retardancy of PA 6,6 fabric in terms of the heat release rate from CCT analysis, but it failed other burning measurements, such as LOI and VBT.

Synthesis of a phosphorus–nitrogen-containing flame retardant and its application in epoxy resin

2018 ◽  
Vol 31 (2) ◽  
pp. 186-196 ◽  
Author(s):  
Shuang Yang ◽  
Yefa Hu ◽  
Qiaoxin Zhang
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Epoxy Resin ◽  
Heat Release Rate ◽  
Flame Retardancy ◽  
Release Rate ◽  
Epoxy Resins ◽  
Proton Nuclear Magnetic Resonance ◽  
Scanning Calorimetry ◽  
Cone Calorimeter Test

In this article, a phosphorus–nitrogen-containing flame retardant (DOPO-T) was successfully synthesized by nucleophilic substitution reaction between 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and cyanuric chloride. The chemical structure of DOPO-T was characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance (NMR) and phosphorous-31 NMR, and elemental analysis. DOPO-T was then blended with diglycidyl ether of bisphenol-A to prepare flame-retardant epoxy resins. Thermal properties, flame retardancy, and combustion behavior of the cured epoxy resins were evaluated by differential scanning calorimetry, thermogravimetric analysis, limited oxygen index (LOI) measurement, UL94 vertical burning test, and cone calorimeter test. The results indicated that the glass transition temperature ( Tg) and temperature at 5% weight loss of epoxy resin (EP)/DOPO-T thermosets were gradually decreased with the increasing content of DOPO-T. DOPO-T catalyzed the decomposition of EP matrix in advance. The flame-retardant performance of EP thermosets was significantly enhanced with the addition of DOPO-T. EP/DOPO-T-0.9 sample had an LOI value of 36.2% and achieved UL94 V-1 rating. In addition, the average of heat release rate, peak of heat release rate, average of effective heat of combustion, and total heat release (THR) of EP/DOPO-T-0.9 sample were decreased by 32%, 48%, 23%, and 31%, respectively, compared with the neat EP sample. Impressively, EP/DOPO-T thermosets acquired excellent flame retardancy under low loading of flame retardant.

scholarly journals Flame-Retardant and Thermal Degradation Mechanism of Caged Phosphate Charring Agent with Melamine Pyrophosphate for Polypropylene

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Xuejun Lai ◽  
Jiedong Qiu ◽  
Hongqiang Li ◽  
Xingrong Zeng ◽  
Shuang Tang ◽  
...  
Keyword(s):  
Thermal Degradation ◽  
Heat Release ◽  
Flame Retardant ◽  
Heat Release Rate ◽  
Release Rate ◽  
Degradation Mechanism ◽  
Limiting Oxygen Index ◽  
Thermal Degradation Mechanism ◽  
Charring Agent ◽  
Ul 94

An efficient caged phosphate charring agent named PEPA was synthesized and combined with melamine pyrophosphate (MPP) to flame-retard polypropylene (PP). The effects of MPP/PEPA on the flame retardancy and thermal degradation of PP were investigated by limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimetric test (CCT), and thermogravimetric analysis (TGA). It was found that PEPA showed an outstanding synergistic effect with MPP in flame retardant PP. When the content of PEPA was 13.3 wt% and MPP was 6.7 wt%, the LOI value of the flame retardant PP was 33.0% and the UL-94 test was classed as a V-0 rating. Meanwhile, the peak heat release rate (PHRR), average heat release rate (AV-HRR), and average mass loss rate (AV-MLR) of the mixture were significantly reduced. The flame-retardant and thermal degradation mechanism of MPP/PEPA was investigated by TGA, Fourier transform infrared spectroscopy (FTIR), TG-FTIR, and scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDXS). It revealed that MPP/PEPA could generate the triazine oligomer and phosphorus-containing compound radicals which changed the thermal degradation behavior of PP. Meanwhile, a compact and thermostable intumescent char was formed and covered on the matrix surface to prevent PP from degrading and burning.

scholarly journals Enhanced Thermal Insulation and Flame-Retardant Properties of Polyvinyl Alcohol-Based Aerogels Composited with Ammonium Polyphosphate and Chitosan

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
MinYi Luo ◽  
Jiayou Xu ◽  
Shu Lv ◽  
XueFeng Yuan ◽  
Xiaolan Liang
Keyword(s):  
Polyvinyl Alcohol ◽  
Heat Release ◽  
Flame Retardant ◽  
Thermal Insulation ◽  
Heat Release Rate ◽  
Flame Retardancy ◽  
Release Rate ◽  
Ammonium Polyphosphate ◽  
Composite Aerogel ◽  
Composite Aerogels

Polyvinyl alcohol- (PVA-) based aerogels have attracted widespread attention owing to their low cost, eco-friendliness, and low density. However, the applications of PVA-based aerogels are limited by their flammability. In this study, a flame retardant, ammonium polyphosphate (APP), and a biopolymer, chitosan (CS), were added to polyvinyl alcohol (PVA), and the polymer was further crosslinked using boric acid (H3BO3). In the PVA aerogels, the negatively charged APP and positively charged CS formed a polyelectrolyte complex (PEC) through ionic interaction. Cone calorimetry and vertical burning tests (UL-94) indicated that the PVA composite aerogels have excellent flame retardancy; they could decrease the heat release rate, total heat release rate, and carbon dioxide (CO2) generation. Both PVA/H3BO3 and APP-CS in the composite aerogel could be burned to carbon, and the foamed char layer could act together to impart the PVA composite aerogels with good flame retardancy. Further, the decrease in the temperature at the backside of the aerogels with increasing APP-CS content, as determined by the flame-spraying experiment, indicated that the PVA-based aerogels with APP-CS can also serve as thermal insulation materials. This work provides an effective and promising method for the preparation of PVA-based aerogels with good flame retardancy and thermal insulation property for construction materials.

The influence of various/different ratios synthetic fiber mixture on the mechanical, thermal, morphological and flammability properties of poly (lactic acid)/polycarbonate blend

2020 ◽  
pp. 002199832096353
Author(s):  
Seda Hazer ◽  
Ayse Aytac
Keyword(s):  
Lactic Acid ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Control Sample ◽  
Synthetic Fiber ◽  
Poly Lactic Acid ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Limiting Oxygen Index

Poly (Lactic Acid) (PLA)/Polycarbonate (PC) blend has gained much attention as a bio-based polymeric material in various industrial fields. This study aims to improve the properties of PLA/PC blend reinforced with glass fiber (GF) and carbon fiber (CF) mixture to be produced for industrial use. For this purpose, 50PLA/50PC blend was prepared and used as a control sample. Then, 30% by weight CF and 30% GF were added to the matrix separately. To examine the effect of the use of CF and GF together, the composites were prepared as a mixture form of fibers by adding 5-10-15% CF and 5-10-15% GF, respectively, to the control blend in pairs. All composites compounded with the laboratory-scale twin-screw mini extruder and molded by injection molding. The effects of using synthetic fiber mixture were evaluated in terms of the mechanical, thermal and flammability properties. Differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), tensile test, scanning electron microscopy (SEM), limiting oxygen index (LOI), heat release rate (HRR) test were carried for the characterization of composites. The highest tensile strength values ​​and maximum % crystallinity values were obtained for the 15CF/15GF fiber mixture containing PLA/PC composite as 113.7 MPa and 21.4, respectively. CO yield (COY), HRR, and total heat release rate were reduced significantly by using synthetic fibers and fiber mixture.

scholarly journals A Study of the Thermal Degradation and Combustion Characteristics of Some Materials Commonly Used in the Construction Sector

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1833 ◽  
Author(s):  
Javier Arturo Piedrahita Solorzano ◽  
Khalid Abu Mohammad Moinuddin ◽  
Svetlana Tretsiakova-McNally ◽  
Paul Joseph
Keyword(s):  
Thermal Degradation ◽  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Inner Core ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Combustion Heat ◽  
Internal Core ◽  
Combustion Flow

In the present work, some materials that are commonly used in the construction industry were studied with regard to their thermal degradation characteristics and combustion attributes. These included façade materials for pre-fabricated houses, such as the layers of cross-laminated timber (CLT) and the inner core of aluminium composite panels (ACPs). The relevant investigations were carried out by employing thermo-gravimetric analysis (TGA) and pyrolysis combustion flow calorimetry (PCFC). The Arrhenius parameters and the associated calorimetric quantities, i.e., heat release rates, temperature to the peak heat release rate, heats of combustion, heat release capacities, and char yields, were also evaluated. These parameters showed that CLT is more fire retarded than the polymeric internal core of ACP façade materials. Furthermore, some valuable correlations among the various test quantities were found. For instance, a good correlation exists between the general profiles of the thermograms obtained through TGA runs and the heat release rate (HRR) traces from PCFC measurements. Depending on the nature of the materials, the char yields measured by PCFC can be 4–20 times higher than the ones obtained through TGA.

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