Effect of carbon fiber amount and length on flame retardant and mechanical properties of intumescent polypropylene composites

2017 ◽  
Vol 52 (4) ◽  
pp. 519-530 ◽  
Author(s):  
Lemiye Atabek Savas ◽  
Aysenur Mutlu ◽  
Ali Sinan Dike ◽  
Umit Tayfun ◽  
Mehmet Dogan

The effects of carbon fiber amount and length were studied on the flame retardant, thermal, and mechanical properties of the intumescent polypropylene composites. The flame retardant properties of the intumescent polypropylene-based composites were investigated using limiting oxygen index, vertical burning test (UL-94), and mass loss calorimeter. The mechanical properties of the composites were studied using tensile test and dynamic mechanical analysis. According to the flammability tests results, the antagonistic interaction was observed between carbon fiber and ammonium polyphosphate. The limiting oxygen index value reduced steadily as the added amount of carbon fiber increased. Mechanical test results revealed that the addition of carbon fiber increased the tensile strength and the elastic modulus as the added amount increased. No effect of carbon fiber length was observed on the flammability, fire performance, and tensile properties of composites, whereas the elastic modulus increased as the carbon fiber initial length increased.

2011 ◽  
Vol 175-176 ◽  
pp. 465-468 ◽  
Author(s):  
Lei Shi ◽  
Hua Wu Liu ◽  
Ping Xu ◽  
Dang Feng Zhao

Plain weave fabrics of polyacrylonitrile pre-oxidation yarns (PANOF) were prepared by small rapier loom. The flame retardation properties, mechanical properties and wear behaviors of PANOF plain weave fabrics were tested. The limiting oxygen index (LOI) of these PANOF plain weave fabric samples was 31%, which meets the criterion of flame-retardant fabrics. These fabrics neither melt nor shrunk when left in flame for a short period of time and the fabric structures were well maintained. Compared with flammable polyacrylonitrile fabrics, the polyacrylonitrile pre-oxidation fabrics exhibited excellent flame retardation properties, with satisfactory mechanical properties and comfortable handle.


2015 ◽  
Vol 30 (6) ◽  
pp. 816-826 ◽  
Author(s):  
Yiren Huang ◽  
Jianwei Yang ◽  
Zhengzhou Wang

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.


2013 ◽  
Vol 791-793 ◽  
pp. 72-75
Author(s):  
Zheng Zhou Wang ◽  
Shao Hong Xu ◽  
Yan Ping Deng

Flammability of polyethylene glycol toughened phenolic (PF) foams containing nanomelamine phosphate (NMP), nanomelamine cyanurate (NMCA) or their capsules was studied by limiting oxygen index (LOI). The effect of the nanoparticles and their micro counterparts on flame retardant and mechanical properties of the toughened foams is compared.


2011 ◽  
Vol 418-420 ◽  
pp. 540-543 ◽  
Author(s):  
Ding Meng Chen ◽  
Yi Ping Zhao ◽  
Jia Jian Yan ◽  
Li Chen ◽  
Zhi Zhi Dong ◽  
...  

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.


2013 ◽  
Vol 671-674 ◽  
pp. 1809-1812
Author(s):  
Shao Hong Xu ◽  
Xiao Yu Sui ◽  
Zheng Zhou Wang

Flammability of toughened phenolic (PF) foams containing ammonium polyphosphate (APP), melamine phosphate (MP) or melamine cyanurate(MCA) was studied by limiting oxygen index (LOI). The LOI values show that APP or MP is an effient flame retardant than MCA in the toughened PF foams. The thermal decomposition and mechanical properties of the phenolic foams were also investigated.


2020 ◽  
Vol 15 ◽  
pp. 155892501989894
Author(s):  
Xiaolu Sun ◽  
Jiayin Song ◽  
Jin Zhang ◽  
Jingyan Liu ◽  
Huizhen Ke ◽  
...  

Polyacrylonitrile-based pre-oxidized fibers with improved thermal stability, flame retardant, and mechanical properties were made from the pristine polyacrylonitrile fibers through chemical pretreatment followed by pre-oxidation in air. The morphological structure of the polyacrylonitrile-based pre-oxidized fibers was investigated by Fourier transfer infrared spectra, X-ray diffraction, scanning electron microscopy, and X-ray energy dispersive spectrometer. The changes of characteristic functional groups and chemical compositions confirmed the successful modification of the polyacrylonitrile fibers during pre-treatment. The grooves and cracks on the surface of polyacrylonitrile-based pre-oxidized fibers were remarkably decreased in comparison with that of pristine polyacrylonitrile fibers. The evolution of crystalline structure of the polyacrylonitrile fibers proved the occurrence of cyclization reactions during pre-oxidation. Meanwhile, thermal stability, flame retardant, and mechanical properties of polyacrylonitrile-based pre-oxidized fibers were also investigated by thermogravimetric analyzer, oxygen index meter, micro combustion calorimeter, and single fiber tensile tester, respectively. The results demonstrated that the polyacrylonitrile-based pre-oxidized fibers initially pre-treated by hydroxylamine hydrochloride, followed by monoethanolamine, had a high limiting oxygen index of 40.1 and breaking strength of 2.03 cN/dtex. The peak of heat release rate and total heat release of polyacrylonitrile-based pre-oxidized fibers decreased significantly while its charred residues increased, contributing to the improved flame retardant property.


Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 534
Author(s):  
Jingyu Wang ◽  
Hui Shi ◽  
Pinlie Zhu ◽  
Yuanjie Wei ◽  
Jianwei Hao

A zeolite imidazole framework (ZIF-67) was assembled onto the surface of ammonium polyphosphate (APP) for preparing a series multifunctional flame-retardant APP-ZIFs. The assembly mechanism, chemical structure, chemical compositions, morphology, and specific surface area of APP-ZIFs were characterized. The typical APPZ1 and APPZ4 were selected as intumescent flame retardants with dipentaerythritol (DPER) because of their superior unit catalytic efficiency of cobalt by thermogravimetric analysis. APPZ1 and APPZ4 possessed 6.8 and 92.1 times the specific surface area of untreated APP, which could significantly enhance the interfacial interaction, mechanical properties, and migration resistance when using in ethylene-vinyl acetate (EVA). With 25% loading, 25% APPZ4/DPER achieved a limiting oxygen index value of 29.4% and a UL 94 V-0 rating, whereas 25% APP/DPER achieved a limiting oxygen index value of only 26.2% and a V-2 rating, respectively. The peak of the heat release rate, smoke production rate, and CO production rate respectively decreased by 34.7%, 39.0%, and 40.1%, while the char residue increased by 91.7%. These significant improvements were attributed to the catalytic graphitization by nano cobalt phosphate and the formation of a more protective char barrier comprised of graphite-like carbon.


2012 ◽  
Vol 534 ◽  
pp. 304-308 ◽  
Author(s):  
Ming Lin Song ◽  
Ya Wen Huang ◽  
Ke Cao ◽  
Jun Xiao Yang

A new silicon-phosphorus hybrid (SPH) flame retardant was synthesized by condensation reaction of 1-oxo-4-hydroxymenthyl-2,6,7-trioxa-1-phosphabicy[2,2,2] octane (PEPA) with waste silicon oil which is mainly consisted of the compounds of CxHySizCln. The effect of Si/P hybrid on the flame retardancy of polypropylene composites (PP/Si-P) was studied by limiting oxygen index (LOI) test and thermogravimetric analysis (TGA). The flame retarding performance of PP/SPH/MP/PER at the same loading amount is slightly higher relative to MP/PER. This, in plus to the low cost and the value in environmental protecting, makes SPH possess the application potential in flame retardants.


Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 902
Author(s):  
Yu Guo ◽  
Meihui Zhou ◽  
Guang-Zhong Yin ◽  
Ehsan Kalali ◽  
Na Wang ◽  
...  

We aimed to study the impact of surface modification of basalt fiber (BF) on the mechanical properties of basalt fiber-based epoxy composites. Four different types of pretreatment approaches to BF were used; then a silane coupling agent (KH550) was applied to further modify the pretreated BF, prior to the preparation of epoxy resin (EP)/BF composites. The combination of acetone (pre-treatment) and KH550 (formal surface treatment) for basalt fiber (BT-AT) imparted the EP/BF composite with the best performance in both tensile and impact strengths. Subsequently, such modified BF was introduced into the flame-retardant epoxy composites (EP/AP750) to prepare basalt fiber reinforced flame-retardant epoxy composite (EP/AP750/BF-AT). The fire behaviors of the composites were evaluated by vertical burning test (UL-94), limiting oxygen index (LOI) test and cone calorimetry. In comparison to the flame-retardant properties of EP/AP750, the incorporation of BF-AT slightly reduced LOI value from 26.3% to 25.1%, maintained the good performance in vertical burning test, but increased the peak of the heat release rate. Besides, the thermal properties and mechanical properties of the composites were investigated by thermogravimetric analysis (TGA), universal tensile test, impact test and dynamic mechanical analysis (DMA).


Sign in / Sign up

Export Citation Format

Share Document