Synergistic effects between boron phosphate and microencapsulated ammonium polyphosphate in flame‐retardant thermoplastic polyurethane composites

Abstract

Microencapsulated ammonium polyphosphate (MAPP) with polyurethane resin has been prepared by in situ polymerization. The combination of MAPP and boron phosphate (BP) on the flammability properties of thermoplastic polyurethane (TPU) was studied by vertical burning (UL‐94) tests, limiting oxygen index tests, cone calorimetry (CONE), and microscale combustion calorimeter (MCC) whereas thermal stability was investigated by thermogravimetric analysis and real‐time Fourier transform infrared. Results showed that a suitable substitution of MAPP by BP could improve flame retardancy of the TPU/MAPP composites and TPU composites with MAPP/BP (15.5/2 wt%) achieving UL‐94 V‐0 rating. The CONE and MCC data showed synergistic effects between BP and MAPP in the composites. Copyright © 2011 John Wiley & Sons, Ltd.

Catalytic pyrolysis and flame retardancy of epoxy resins with solid acid boron phosphate

“…BP is an active catalyst in the dehydration of alcohols [20], and has also been used as an additive in glass and ceramic production [21,22]. In recent years BP has been used as flame retardant additive in different polymer systems such as polyamide [23,24], polypropylene [25], polyurethane [26] and polyimide [27] due to its low cost, low toxicity, low evolution of smoke and its effectiveness. However, to the best of our knowledge, very little is known about the detailed mechanism for improving flame retardancy in polymer matrices, and there are no published studies on catalytic flame retardant effects due to the solid acid character of BP.…”

Synergistic effects between iron-graphene and ammonium polyphosphate in flame-retardant thermoplastic polyurethane

“…In the case of TPU1 with only APP, the initial decomposition temperature is 304.2°C, which is lower than that of neat TPU. This can be attributed to the decomposition of APP at low temperature [37]. As usual, thermal degradation of TPU has two steps: The first stage is responsible for the rupture of the TPU main chains, whereas the second stage is attributed to the further destruction of the C-C and C-O bonds on the main chain [30].…”

Surface modification of α‐zirconium phosphate by zeolitic imidazolate frameworks‐8 and its effect on improving the fire safety of polyurethane elastomer

“…Polyurethane elastomer (PUE) is mainly composed of hard and soft segments, and the soft segments are usually polyols, while the hard segments are generally isocyanates and chain extenders. Because of its excellent elasticity, radiation resistance, abrasion resistance, and low temperature resistance, PUE is widely used in many industries, such as mining, machinery, construction, and auto‐making . But PUE is easy to burn in air and produces toxic gases, such as HCN and CO, which can cause serious harm to human health and the environment.…”