scholarly journals Polyvinyl Alcohol Reinforced Flame-Retardant Polyacrylonitrile Composite Fiber Prepared by Boric Acid Cross-Linking and Phosphorylation

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2391 ◽  
Author(s):  
Yuanlin Ren ◽  
Tian Tian ◽  
Lina Jiang ◽  
Xiaohui Liu ◽  
Zhenbang Han

To improve the strength and maintain the inherent properties of flame-retardant polyacrylonitrile (FR-PAN) fiber, a commercialized hydrocarbon polymer, i.e., poly (vinyl alcohol) (PVA), used as an enhancement component, was blended with polyacrylonitrile (PAN) spinning dope to fabricate a PVA/PAN composite fiber through wet-spun technology. Then, cross-linked PVA/PAN composite fiber (C-PVA/PAN) was acquired via boric acid cross-linking. Finally, flame-retardant C-PVA/PAN fiber (FR-PVA/PAN) was prepared by phosphorylation. The structures of the samples were characterized by Fourier transform infrared analysis (FTIR) and X-ray photoelectron spectroscopy (XPS). The thermogravimetric analysis (TGA) results reveal that the thermal stability of the composite fiber is lower than that of the pristine PAN fiber. However, the char residue of the composite fiber is higher than that of the control sample, wherein, FR-PVA/PAN has the highest char residue of 62.5 wt% at 800 °C. The results regarding the combustion properties of FR-PVA/PAN show that the fire hazard of FR-PVA/PAN is restrained greatly, indicating excellent flame-retardant performance. The corresponding flame-retardant mechanism of FR-PAV/PAN is investigated by Pyrolysis gas chromatography and mass spectrometry (Py-GC/MS) and thermogravimetric analysis coupled with Fourier transform infrared analysis (TG-FTIR). The results indicate the gas-phase and condensed-phase flame-retardant mechanisms.

2004 ◽  
Vol 18 (6) ◽  
pp. 1814-1821 ◽  
Author(s):  
Haiping Yang ◽  
Rong Yan ◽  
Terence Chin ◽  
David Tee Liang ◽  
Hanping Chen ◽  
...  

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3588
Author(s):  
Jiayi Chen ◽  
Yansong Liu ◽  
Jiayue Zhang ◽  
Yuanlin Ren ◽  
Xiaohui Liu

Lyocell fabrics are widely applied in textiles, however, its high flammability increases the risk of fire. Therefore, to resolve the issue, a novel biomass-based flame retardant with phosphorus and nitrogen elements was designed and synthesized by the reaction of arginine with phosphoric acid and urea. It was then grafted onto the lyocell fabric by a dip-dry-cure technique to prepare durable flame-retardant lyocell fabric (FR-lyocell). X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR) analysis demonstrated that the flame retardant was successfully introduced into the lyocell sample. Thermogravimetric (TG) and Raman analyses confirmed that the modified lyocell fabric featured excellent thermal stability and significantly increased char residue. Vertical combustion results indicated that FR-lyocell before and after washing formed a complete and dense char layer. Thermogravimetric Fourier-transform infrared (TG-FTIR) analysis suggested that incombustible substances (such as H2O and CO2) were produced and played a significant fire retarding role in the gas phase. The cone calorimeter test corroborated that the peak of heat release rate (PHRR) and total heat release (THR) declined by 89.4% and 56.4%, respectively. These results indicated that the flame retardancy of the lyocell fabric was observably ameliorated.


Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1997 ◽  
Author(s):  
Zhi Wang ◽  
Ruichao Wei ◽  
Xuehui Wang ◽  
Junjiang He ◽  
Jian Wang

To fill the shortages in the knowledge of the pyrolysis and combustion properties of new and aged polyvinyl chloride (PVC) sheaths, several experiments were performed by thermogravimetric analysis (TG), Fourier transform infrared (FTIR), microscale combustion calorimetry (MCC), and cone calorimetry. The results show that the onset temperature of pyrolysis for an aged sheath shifts to higher temperatures. The value of the main derivative thermogravimetric analysis (DTG) peak of an aged sheath is greater than that of a new one. The mass of the final remaining residue for an aged sheath is also greater than that of a new one. The gas that is released by an aged sheath is later but faster than that of a new one. The results also show that, when compared with a new sheath, the heat release rate (HRR) is lower for an aged one. The total heat release (THR) of aged sheath is reduced by 16.9–18.5% compared to a new one. In addition, the cone calorimetry experiments illustrate that the ignition occurrence of an aged sheath is later than that of a new one under different incident heat fluxes. This work indicates that an aged sheath generally pyrolyzes and it combusts more weakly and incompletely.


2017 ◽  
Vol 48 (1) ◽  
pp. 87-118 ◽  
Author(s):  
MD Teli ◽  
Pintu Pandit

As far as the value addition of textile is concerned, flame retardancy of textile materials is considered to be one of the most important properties in textile finishing by both industries as well as academic researchers. Flame-retardant property with thermal stability was imparted to cotton by using green coconut ( Cocos nucifera Linn) shell extract, a natural waste source of coconut. Coconut shell extract was analyzed by high-performance liquid chromatography, Fourier transform infrared spectroscopy, energy-dispersive spectrometry and its phytochemical analysis was also carried out. The coconut shell extract (acidic after extraction) was applied in three different pH (acidic, neutral, and alkaline) conditions to the cotton fabric. Flame-retardant properties of the untreated and the treated cotton fabrics were analyzed by limiting oxygen index and vertical flammability. The study showed that all the treated fabrics had good flame resistance property compared to that of the untreated fabric. The limiting oxygen index value was found to increase by 72.2% after application of the coconut shell extract from alkaline pH. Pyrolysis and char formation behavior of the concerned fabrics were studied using thermogravimetric analysis and differential scanning calorimetric analysis in a nitrogen atmosphere. The physicochemical composition of the untreated and coconut shell extract treated cotton fabrics were analyzed by attenuated total reflection–Fourier transform infrared, scanning electron microscope, and energy-dispersive X-ray spectroscopy. Also, treated cotton fabric showed natural brown color and antibacterial property against both Gram-positive and Gram-negative bacteria. The durability of the flame-retardant functionality to washing with soap solution has also been studied and reported in this paper.


Sign in / Sign up

Export Citation Format

Share Document