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In recent years, thermoplastic polyurethane elastomer has shown great application prospects in the fields of polymer film due to its outstanding tensile properties, high elasticity, wear resistance, oil resistance, low temperature resistance, wide range of hardness, and other properties. However, its flammable properties greatly limit its application in the field of polymer film. The self-made GO was used as a carbon source, phenylboronic acid as an acid source, ammonium polyphosphate (APP) as an acid and gas source, and intumescent flame retardant (IFR) was compounded. The IFR was introduced into thermoplastic polyurethane (TPU) to prepare a series of IFR/TPU composite films with different formulations. The results show that PA and GO can make up for the loss of mechanical properties caused by the addition of APP and improve the thermal stability of the composite film, and the IFR flame retardant composed of the two and APP can effectively improve the flame retardancy of the composite film. When the additions of APP, PA, and GO were 10, 3, and 0.75%, respectively, the LOI value of the IFR/TPU composite material reached 29.5, the flame-retardant grade reached V-0, and its peak heat release rate, total heat release, peak smoke production rate, and total smoke release were 86.0, 64.9, 70.5, and 21.7%, greatly lower than pure TPU, respectively. The flame retardancy of the spacer composite membrane constructed from Ti-7 was significantly improved, and the burn-through time of the single-layer film sample was increased by 2.22 times, and the double-layer film sample was increased by 2.63 times. [ABSTRACT FROM AUTHOR]

With the widely application of thermoplastic polyurethane elastomer (TPU), the fire safety of the TPU composites has attracted more and more attention. In this work, a highly efficient and green flame retardant (DA-APP) was synthesized via the ion exchange reaction between biologically relevant molecule dopamine (DA) and ammonium polyphosphate (APP). When the incorporation amount of DA-APP was 5 wt%, it was found that TPU/DA-APP5 passed the V-0 rating and the LOI reached to 25.9%. Meanwhile, the peak heat release rate (PHRR) of TPU composite decreased by 732.5 kW m−2 and total heat release decreased by 19.7 MJ m−2 and total smoke release decreased by 33.6 m2 compared to that of the neat TPU. Moreover, the flame-retarding mechanism of TPU/DA-APP5 was analyzed by TG-FTIR and Raman characterization. The results showed that DA-APP produced amino compounds and phosphoric acid at low temperature, promoted TPU to produce water and carbon dioxide, and diluted oxygen concentration during combustion. In addition, the dense carbon layer formed on the surface of TPU played an important role to isolate the diffusion of heat and oxygen. [ABSTRACT FROM AUTHOR]

Thermoplastic polyurethane was an important polymer and widely used in many fields. However, poor fire performance significantly inhibits its further application. In this study, the flammability, thermal and mechanical properties of thermoplastic polyurethane (TPU)/DOPO derivative (DiDOPO)/sepiolite composites, fabricated by a melt blending process, were examined based on the sepiolite content. TPUSEP3 has achieved UL-94 V0 classes and LOI 34.4%. Micro-scale combustion calorimeter shows that TPU/DiDOPO/sepiolite composites possess an excellent fire performance. Flexural strength of TPUSEP3 has enhanced to 48.3 MPa which indicated the rigidity of composites has significantly improved. In addition, the scanning electronic microscopy images of the external surface of the carbon layer of composites show a very compact structure. Sepiolite and DiDOPO change the decomposition process of composites lead to the decrease of Ea values of TPU/DiDOPO/sepiolite composites. [ABSTRACT FROM AUTHOR]

Thermoplastic polyurethane elastomer (TPU) had a wide application because of the perfect property, while it was still limited by its flammability and flame dripping. In this paper, modified molecular sieve (MMS) by 1-((ethoxycarbonyl)methyl)-3-methylimidazolium hexafluorophosphate ([EOOEMIm][PF6]) was used into TPU as a type of flame agent. The flame-retardant performance of TPU was studied by cone calorimeter (CCT), smoke density test (SDT) and thermogravimetric/infrared spectroscopy (TG-IR), respectively. CCT test indicated that MMS improved flame-retardant performance of TPU effectively by promote the formation of char layer. The peak heat release rate and total heat release declined by 48.4% and 32.5%, respectively, compared to pure TPU when 1.0 mass% MMS was added; SDT test showed that MMS improved the smoke generation performance of TPU without flame; and the TG-IR test proved that MMS improved the thermal stability of TPU even though in nitrogen. So the MMS can apply for flame-retardant TPU well in the future. [ABSTRACT FROM AUTHOR]

In this paper, 1-aminoethyl-3-methylimidazolium hexafluorophosphate ([APMIm]PF6) and 1-butyl-3-methylimidazolium hexafluorophosphate ([EMIM]PF6) were used as flame retardant additives in thermoplastic polyurethane elastomer (TPU). The flame retardant effect of [APMIm]PF6 and [EMIM]PF6 in TPU had been investigated by cone calorimeter (CCT), scanning electron microscope (SEM), energy-dispersive spectroscopy (EDS), microcombustion calorimeter (MCC), fourier transform infrared spectroscopy (FT-IR), smoke density test (SDT), thermogravimetric analysis (TG) and thermogravimetric/fourier transform infared spectroscopy (TG-IR), respectively. The results indicated that TPU/[APMIm]PF6 had better thermal properties compared with pure TPU and TPU/[EMIM]PF6. The peak heat release rate (pHRR) of TPU/A-1.0 was remarkably reduced by 32.97% and 19.15%, in comparison with that of TPU and TPU/E-1.0. Moreover, the total heat release (THR) and smoke production rate (SPR) of TPU/A-1.0 were the lowest among all samples. And, in the early stage of fire, [APMIm]PF6 can promote the formation of protective carbon layer, reduce the HRR and SPR. Therefore, it is necessary to develop environment-friendly green flame retardants. [ABSTRACT FROM AUTHOR]

As is known there is a large amount of smoke released from the combustion process of thermoplastic polyurethane elastomer (TPU). To reduce the fire risk of TPU is one of the research contents in the fire safety fields. In this paper, [Glu]H2PW12O40 was used as smoke suppressant in TPU, and the smoke suppression effect of [Glu]H2PW12O40 was intensively investigated using nuclear magnetic resonance, scanning electron microscope, cone calorimeter test (CCT), smoke density test (SDT), and thermogravimetric analysis/infrared spectrometry, respectively. In the CCT test, the peak value of smoke production rate (SPR) of TPU-3 with 0.5 mass% of [Glu]H2PW12O40 was 0.036 m2 s−1, reduced by 75% compared with the peak SPR value of TPU-0 without [Glu]H2PW12O40 (0.145 m2 s−1). [Glu]H2PW12O40 could decrease the total smoke release (TSR) from 1560 to 694 m2 m−2. And [Glu]H2PW12O40 could decrease the smoke factor from 1838 to 538 W m−2. The SDT results showed that the luminous flux value of TPU-3 with 0.5 mass% of [Glu]H2PW12O40 decreased by 30% compared with pure TPU at the end of the test without flame. The photographs from the CCT test showed that [Glu]H2PW12O40 could promote char residue formation. TG test also revealed that [Glu]H2PW12O40 could improve the thermal stability at high temperature. At the end of thermal decomposition, the mass of TPU-3 with 0.5 mass% of [Glu]H2PW12O40 increased 6.3% compared with the mass of TPU-0 without [Glu]H2PW12O40. Based on the above result, it could be concluded that [Glu]H2PW12O40 can suppress smoke generation by promoting char generation. In addition, [Glu]H2PW12O40 has a good prospect in smoke suppression of TPU. [ABSTRACT FROM AUTHOR]

Molecular sieve was applied to chemical industry diffusely as a typical catalyst. Meanwhile, much molecular sieve was abandoned, which leads to the waste of resources and environmental pollution. It became a research hot spot to recycle abandoned molecular sieve (AMS). In this paper, AMS was used as a flame-retardant and smoke-suppressant agent in TPU. The performance of flame retardant and smoke suppressant of samples was tested by cone calorimeter, smoke density test and thermogravimetric/infrared spectroscopy (TG–IR), respectively. The results showed that AMS could improve the performance of flame retardant and smoke suppressant of TPU effectively. The pHRR and TSR declined by 55.0% and 48.4%, respectively, and the luminous flux increased 5.53% when the addition of molecular sieve was 1.0 mass%. TG–IR results showed that AMS can improve the thermal stability of TPU even under nitrogen atmosphere. It can be concluded that AMS has a good application prospect in flame retardant and smoke suppressant of TPU, and a new idea for the disposal of AMS was provided. [ABSTRACT FROM AUTHOR]

This article mainly studied the synergistic fire safety effect between nano-CuO and ammonium polyphosphate (APP) in thermoplastic polyurethane elastomer (TPU). The TPU composites were prepared by molten blending method. And the fire safety of all TPU composites was investigated by LOI test, cone calorimeter test (CCT), microscale combustion colorimeter (MCC) and smoke density test (SDT), respectively. The LOI test showed that nano-CuO could further improve the flame retardancy of TPU. The CCT results showed that there was a remarkably synergistic fire safety effect between APP and nano-CuO in TPU. Remarkably, the total heat release and total smoke release for the sample with 0.5 mass% content of nano-CuO decreased by at least 13.0 and 51.1% compared with the sample containing only APP, respectively. And the residual carbon mass of the samples containing nano-CuO was more than that of the sample with only APP at the end of the test. The MCC results showed that the HRR values of the samples containing nano-CuO were further lower than that of the sample containing APP. The SDT results showed that the luminous flux values of the samples containing nano-CuO were higher than that of the sample with only APP irrespective of with flame or without flame, which indicated that there was an apparently synergistic effect of smoke suppression between APP and nano-CuO in TPU. Through the analysis of the results of this experiment, it will make a great influence on the study of the nanomaterials in the aspect of fire safety of polymer. [ABSTRACT FROM AUTHOR]