A novel P/N-based flame retardant synthesized by one-step method toward cotton materials and its flame-retardant mechanism

Abstract

A novel flame retardant containing phosphorus and nitrogen elements, ammonium salt of N,Ndimethylene p-benzenesulfonic phosphonic acid (ADBSPA), was prepared by one-step continuous chemical method. The chemical structure of the ADBSPA was determined by nuclear magnetic resonance spectrum (NMR) and Fourier transform infrared (FTIR), and ADBSPA was processed onto cotton materials by immersion method. The flame retardancy of coated cotton materials was analyzed by limiting oxygen index (LOI) and Vertical burning test. The LOI value of cotton coated with 350 g/L ADBSPA increased from the original 18.2 ± 0.2% to 31.7 ± 0.2%, and the damaged length of this sample reduced to 6.6 ± 0.1 cm, which proved that ADBSPA enhanced the anti-burning ability of cotton materials. Cone calorimetry was used to evaluate the combustion behavior of cotton materials before and after coating. Compared with original sample, ADBSPA changed the combustion path of cotton materials, and the intuitive performance was that the ADBSPA-cotton-4 reserved 25.1 ± 0.5% of char residue at 250 s, and its peak heat release rate (PHRR) greatly reduced to 17 ± 1 kW/m 2 . The surface morphology of uncoated and coated cotton materials was characterized by scanning electron microscopy (SEM). It was observed that the coated sample still maintained a complete fiber skeleton after burning. In addition, thermogravimetric (TG) analysis confirmed that the coated cotton materials had good thermo-oxidative and thermal stability. All results pointed out that the phosphorus and nitrogen elements contained in ADBSPA as well as cotton cellulose constituted the three basic conditions of intumescent flame-retardant system. The polyphosphoric acid compounds formed by phosphorus element at high temperature promoted the dehydration of cotton fibers into char layer. The non-flammable gases produced by the nitrogen element in the combustion process covered the surface of fabrics, thereby playing the role of shielding heat and diluting combustible gases.

Modification of Unfinished Textiles by Cu Deposition Developed by Cold Cathode Ion Source for Antimicrobial Application

“…Figure 3 (a, b) shows the XRD pattern of three types of textiles before and after Cu-NPs deposition. The polyester diffraction peaks (Muthukumar & Thilagavathi, 2012) appeared at 2θ =18.1 º , 23 º , and 26.19 º , whereas that of cotton appeared at 2θ =15.12 º , 16.8 º , 22.92 º , and 34.51 º (Abd- Elhamid et al, 2019;Zhao et al, 2019;Sun et al, 2021). The polyester/cotton sample shows its diffraction peaks at 2θ =16.72 º , 22.89 º , and 25.64 º .…”

“…The band at 1625.11 cm -1 corresponds to O-H bending vibration. The bands at 1427.18 cm -1 and 1317.99 cm -1 are due to C-H wagging and the bands at 1156.17 cm -1 and 1103.53 cm -1 are assigned to C-O-C asymmetric stretching, whereas the band at 1021.89 cm -1 is attributed to C-O stretching (Abd-Elhamid et al, 2019;Zhao et al, 2019;Sun et al, 2021). For the polyester/cotton samples, the O-H stretching vibration appears at 3332.37 cm -1 whereas the C-H stretching vibration is at 2901.09 cm -1 , the characteristic band of the ester group appears at 1711.47 cm -1 , and the band at 1017.90 cm -1 is attributed to C-O stretching.…”

Preparation of multifunctional flame-retardant coating of cotton fabrics for electrical Insulating applications

“…During the pyrolysis of CF, the phosphorus-rich compounds prevent the formation of levoglucosan and flammable volatile compounds and extremely increase the rate of dehydration of cotton cellulose into a char layer. [9][10][11][12][13][14] On the other hand, nitrogen-containing compounds realize flame retardancy in the gas phase. During combustion, the nitrogen-containing compounds degrade and produce non-flammable gases in the combustion zone.…”

Simple and green synthesis of calcium alginate/hydroxyapatite hybrid material without high temperature treatment and its flame retardancy

“…The synergistic effect between natural biomacromolecules and inorganic compounds has been a hot research direction for scientists recently. Compared with the complex and even harmful doping process of organics (Sun et al 2021b), inorganics doping is simpler and more environmentally friendly (Chen et al 2017). In our previous works, the ame retardant properties of CaAlg doped with inorganic substances such as calcium borate (Liu et Hydroxyapatite (Ca 10 (OH) 2 (PO 4 ) 6 , HAP), as an inorganic phosphate, may be effectively improve the ame retardancy of alginate for it possesses a very high decomposition temperature (above 1000 ℃) (Yang et al 2018).…”