Halogen‐free flame‐retardant flexible polyurethane for textile coating: Preparation and characterisation

Abstract

A type of flexible polyurethane (FPU) based on renewable-sourced polyol was prepared and then modified with halogen-free flame retardants, namely, alumina trihydrate (ATH) and triphenyl phosphate (TPhP), to further increase its flameresistant properties. The optimum loading for additives was determined based on analysing the changes in physicomechanical properties, thermal properties, and flame-retardant behaviours of modified FPU materials. An FPU-coated textile was then prepared; its smoke-generating behaviours and flammability were investigated in comparison with pristine fabric, pristine FPU, and respective modified FPU. The results confirmed good synergistic effect between ATH and TPhP, which helped increasing flame-resistant properties of applied materials, while also maintained reasonable flexibility for fabric-coating applications. However, the usage of modified FPU as coating material also proved to cause more toxic smoke emissions during the short burning duration of coated-fabric, an issue that needed to be investigated more thoroughly in order to guarantee the safety of people during catastrophic events.

Synergistic effect of screen-printed Al(OH)3 nanoparticles and phosphorylated cellulose nanofibrils on the thermophysiological comfort and high-intensive heat protection properties of flame-retardant fabric

“…Besides, reduced tear and tensile strengths at rupture are common when ATH NPs are applied to the fabric since NPs form irregular regions and cracks in the matrix, thus making it more susceptible to destruction. 19…”

“…When compared to other related studies, using ATH NPs for textile treatment, the tensile strengths are often deteriorated by between 3 and 18%, dependent on the ATH concentration applied (10-60 wt%), the type of fibres used (natural vs synthetic) and the structure of the fabric. 10,14,19 An (up to 76%) improved tensile strength of the fabric was shown when Mg-Al-layered double hydroxides had been embedded into the coated polymer matrix, 17 or the Al 2 O 3 was coated (up to 10%) by a multilayer coating. 18 On the other hand, due to the fabric`s two-wefts construction, it showed lower tear strength of the warp threads (about 13.5 N) in comparison with the weft threads (about 26 N); that is, the lower density of the warp threads offered lower resistance against tear propagation.…”

“…18 The synergistic thermal effects of polyurethane, ATH NPs and triphenyl phosphate have also been shown when applied on a cotton/polyester fabric. 19 Good thermal insulation and flame resistance of polysulfonamide fabrics were obtained by electrostatic assembling of ATH NPs as a thin layer film on their surface, 10 or the sol-gel deposition method. 20 Boehmite (AlO(OH)), another form of ATH NPs, was also used to treat polyester and cotton fabrics, which increased their residues, slowed the degradation rates, suppressed the dripping effect and changed the degradation profile.…”

Effect of flame‐retardant melamine and dispersants on the mechanical, thermal, and foaming properties of flexible polyurethane foam

“…[8][9][10] In particular, the flame-retardant particles are also not completely dissolved in the polyol premix, making them prone to agglomeration because of their high surface area and energy. 11 Despite various studies on the effects of adding flame retardants to PU foam, [6][7][8][9][10][11][12][13][14][15][16][17][18] only a few studies have been conducted on the combined effect of flame retardants and dispersants on the dispersion of the flame retardant.…”