Flame retardancy and thermal degradation of halogen-free flame-retardant biobased polyurethane composites based on ammonium polyphosphate and aluminium hypophosphite

2017 ◽  
Vol 62 ◽  
pp. 325-334 ◽  
Author(s):  
Haiyang Ding ◽  
Kun Huang ◽  
Shouhai Li ◽  
Lina Xu ◽  
Jianling Xia ◽  
...  
Keyword(s):  
Thermal Degradation ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Ammonium Polyphosphate ◽  
Biobased Polyurethane ◽  
Polyurethane Composites ◽  
Halogen Free

Application of Calculus Equation in Solving Thermal Decomposition Kinetics Parameters of Flame Retardant Wood

2014 ◽  
Vol 983 ◽  
pp. 190-193
Author(s):  
Cai Yun Sun ◽  
Yong Li Yang ◽  
Ming Gao
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Thermal Degradation ◽  
Phosphoric Acid ◽  
Flame Retardant ◽  
Kinetic Parameters ◽  
Flame Retardancy ◽  
Decomposition Kinetics ◽  
Thermal Decomposition Kinetics ◽  
Kinetics Parameters

Wood has been treated with amino resins and amino resins modified with phosphoric acid to impart flame retardancy. The thermal degradation of samples has been studied by thermogravimetry (TG) in air. From the resulting data, kinetic parameters for different stages of thermal degradation are obtained following the method of Broido. For the decomposition of wood and flame retardant wood, the activation energy is found to decrease from 122 to 72 kJmol-1.

scholarly journals Density Effect on Flame Retardancy, Thermal Degradation, and Combustibility of Rigid Polyurethane Foam Modified by Expandable Graphite or Ammonium Polyphosphate

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 668 ◽  
Author(s):  
Yang ◽  
Liu ◽  
Jiang ◽  
Chen ◽  
Wan
Keyword(s):  
Weight Loss ◽  
Thermal Degradation ◽  
Heat Release ◽  
Polyurethane Foam ◽  
Apparent Density ◽  
Flame Retardancy ◽  
Ammonium Polyphosphate ◽  
Expandable Graphite ◽  
Rigid Polyurethane Foam ◽  
Combustion Behaviors

The current study aims at comparatively investigating the effect of apparent density on flame retardancy, thermal degradation and combustion behaviors of rigid polyurethane foam (RPUF), RPUF/ expandable graphite (EG) and RPUF/ ammonium polyphosphate (APP). A series of RPUF, RPUF/EG and RPUF/APP samples with different apparent densities (30, 60 and 90 kg/m3) were prepared. The flame retardancy, thermal degradation, and combustion behaviors of each sample were investigated. Limiting oxygen index (LOI) results indicated that increasing apparent density was beneficial to the flame retardancy of all foam systems. The effect of apparent density on the enhancement of flame retardancy followed the sequence of RPUF < RPUF/APP < RPUF/EG. Thermogravimetric analysis (TGA) results showed that an increase in the apparent density can cause more weight loss in the first degradation stage and less weight loss in the second degradation stage for all foam systems. The combustion behaviors also showed significant differences. The samples with a higher apparent density showed a longer duration of heat release and higher total heat release (THR). The findings in this study demonstrated that apparent density played an important role in flame retardancy, thermal degradation, and combustion behaviors of RPUF, which must be paid more attention in the studies of flame-retardant RPUF.

Flame retardancy and thermal properties of rigid polyurethane foam conjugated with a phosphorus–nitrogen halogen-free intumescent flame retardant

2020 ◽  
Vol 38 (3) ◽  
pp. 235-252
Author(s):  
Zhaojun Lin ◽  
Qianqiong Zhao ◽  
Ruilan Fan ◽  
Xiaoxue Yuan ◽  
Fuli Tian
Keyword(s):  
Thermal Properties ◽  
Thermogravimetric Analysis ◽  
Flame Retardant ◽  
Polyurethane Foam ◽  
Flame Retardancy ◽  
Oxygen Index ◽  
Carbon Layer ◽  
Limited Oxygen Index ◽  
Halogen Free ◽  
Limited Oxygen

In this work, a halogen-free intumescent combining phosphorus and nitrogen, flame-retardant 2-((2-hydroxyphenyl)(phenylamino)methyl5,5-dimethyl-1,3,2-dioxaphosphinane 2-oxide (HAPO) was successfully synthesized. It had been synthesized by reaction of 5,5-dimethyl-1,3, 2-dioxphosphinane 2-oxide with Schiff base. Its chemical structure was characterized in detail by Fourier transform infrared spectroscopy, 1H NMR, and 31P NMR spectrum. The flame-retardant polyurethanes were prepared with different loadings of HAPO. The thermal properties, flame retardancy and combustion behavior of the pure polyurethane foam thermosets were investigated by a series of measurements involving thermogravimetric analysis, limited oxygen index measurement, UL-94 vertical burning test, and cone calorimeter test. The results of the aforementioned tests indicated that HAPO can significantly improve the flame retardancy as well as smoke inhibition performance of polyurethane foam. Compared with the PU-Neat, the limited oxygen index of flame-retardant polyurethanes (15%) thermoset was increased from 19.5% to 23.8% and its UL-94 reached V-0 rating. In addition, the cone test results showed that the heat release rate, total heat release, rate of smoke release, and total smoke production of flame-retardant polyurethanes (10%) were decreased obvious sly. The apparent morphology of carbon residue was characterized by scanning electron microscopy, and results revealed that the modified polyurethane foam can form dense carbon layer after combustion. Thermogravimetric analysis results also indicated that the char amount of flame-retardant polyurethanes was obviously increased compared with PU-Neat. Based on the above analysis, we can draw the conclusions which in the condensed phase, phosphorus-based acids from the degradation of HAPO, this could promote the formation of continuous and dense phosphorus-rich carbon layer. In the gas phase, the flame-retardant mechanism was ascribed to the quenching effect of phosphorus-based radicals and diluting effect by non-flammable gases.

scholarly journals Layer-by-layer assembly flame-retardant and anti-dripping treatment of polyethylene terephthalate fabrics

2019 ◽  
Vol 14 ◽  
pp. 155892501987030
Author(s):  
Yinchun Fang ◽  
Xinhua Liu ◽  
Cuie Wang
Keyword(s):  
Flame Retardant ◽  
Polyethylene Terephthalate ◽  
Flame Retardancy ◽  
Alkali Treatment ◽  
Ammonium Polyphosphate ◽  
Layer By Layer ◽  
Limiting Oxygen Index ◽  
Layer By Layer Assembly ◽  
Branched Polyethylenimine ◽  
Layer Assembly

Layer-by-layer assembly is a simple and effective method which has been widely studied to improve the flame retardancy of textiles in recent years. In this article, flame-retardant and anti-dripping polyethylene terephthalate fabrics were successfully prepared by layer-by-layer assembly branched polyethylenimine and ammonium polyphosphate on their surface. The results of limiting oxygen index values and vertical burning test revealed that the flame retardancy and anti-dripping performance of polyethylene terephthalate fabrics were improved after the layer-by-layer assembly treatment; especially, the dripping phenomenon was eliminated when the number of branched polyethylenimine/ammonium polyphosphate bilayers was over 10. The influence of alkali treatment of polyethylene terephthalate fabrics before layer-by-layer assembly was also investigated. The results showed that alkali treatment of the polyethylene terephthalate fabrics would promote the combination of polyethylene terephthalate fabrics and the charged flame retardants indicating better flame retardancy. The results of thermogravimetric analysis revealed that layer-by-layer assembly treatment of polyethylene terephthalate fabrics would promote char formation both under the nitrogen atmosphere and under the air atmosphere which may act through condensed phase action. The scanning electron microscopy images of the char residues revealed that the layer-by-layer assembly treatment of polyethylene terephthalate fabrics would promote the formation of a compact and intact char residue, which was beneficial for the improvement of flame retardancy and anti-dripping performance. This research would provide the experimental basis for the effective flame retardancy and anti-dripping performance of polyethylene terephthalate fabric.

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