Thermal cross‐linking and anti‐meltdrop properties of copolyester containing phosphorus/magnesium salt composites by in situ polymerization

Abstract

Polyester is widely used in household products because of its good mechanical properties and wears resistance, but polyester is easy to ignite and inclined to produce droplet, so its application range is limited. The cross‐linkable magnesium hydroxide nanoparticles were incorporated into flame‐retardant polyester, which enables the phosphorus‐containing copolyester with thermal cross‐linking and anti‐meltdrop properties. The nanoparticles were achieved by in situ polymerization and acted as a nucleating agent for improving the crystalline properties of the copolyester. Furthermore, the nanoparticles also enhanced anti‐meltdrop properties and reduced the heat and gas release during the combustion process of the copolyester. The maximum heat release rate and total smoke release reduced by 39.8% and 74.4% compared with pure polyester. Specifically, the combustion products of the nanoparticles and phosphorus flame retardant could act a barrier role by covering the carbon layer to isolate air and heat, thereby resulting in excellent anti‐meltdrop properties. The simple modification method reported here realizes the collaborative modification of flame retardant and anti‐meltdrop properties of phosphorous flame‐retardant copolyesters by thermal cross‐linking.

Preparation and thermal cross-linking mechanism of co-polyester fiber with flame retardancy and anti-dripping by in situ polymerization

“…The absorption peak at 3440 cm −1 corresponds to the –OH group, and the characteristic peak increases with the increase of the calcination temperature. The characteristic absorption peaks of PO 2 − , P–O, PO 4 3− , and P 2 O 7 4− (approximately 1100 cm −1 ) 7,47 and the bending vibration peaks of O P–O (471 cm −1 and 499 cm −1 ) are also observed. These indicate that the phosphorus-containing copolyesters form phosphate and phosphite structures during the decomposition process; the strength of the acidic structure increases with the increase of the calcination temperature.…”

“…[1][2][3][4] The polyesters are inherently ammable and exhibit severe dripping behaviour during combustion, making them unsuitable for household textile decoration. [5][6][7] Various approaches have been proposed in previous studies, including the addition of ame retardants into polyesters by blending, and incorporating ame-retardant monomers into the PET chains via polymerisation, and nishing the fabrics/textile in a solution containing ame retardants to improve the properties of retardancy. [8][9][10] However, few solutions have been developed for these problems, owing to the large number of additives required, as well as the poor durability and compatibility of the materials.…”

“…It has been reported that the copolymerisation of polyester with polytetrauoroethylene, silicate, or magnesium hydrate can increase the residual carbon content and decrease the melt uidity to improve the resistance of the droplets. 7,17 Pyrolysis and re behavior of phosphorus polyester (PET-P-DOPO) were studied by Pospiech et al 18,19 They modied PBT with a phosphorus polyester (PET-P-DOPO) as a halogen-free ame retardant. The effects of three different mechanisms (ame retardancy, carbonization and protection of expanded carbon) on the ame retardancy of polyethylene terephthalate were investigated.…”

Highly flame‐retardant and low toxic polybutylene succinate composites with functionalized BN@APP exfoliated by ball milling

“…Most of these intumescent formulations are phosphorus and nitrogen-based organic flame-retardants. [15][16][17][18] These include ammonium polyphosphate (APP), 19,20 melamine, 21,22 and melamine phosphate. 23,24 Chen et al 25 compared APP and microencapsulated APP (MCPP) as flame-retardants in PLA/ramie bio-composites.…”

“…It has been reported that the flame‐retardant PBS is mainly based on an intumescent flame‐retardant system. Most of these intumescent formulations are phosphorus and nitrogen‐based organic flame‐retardants 15–18 . These include ammonium polyphosphate (APP), 19,20 melamine, 21,22 and melamine phosphate 23,24 .…”