Flame Retardancy Of Cotton Fabrics Research Articles

Optimizing Synergistic Silica–Zinc Oxide Coating for Enhanced Flammability Resistance in Cotton Protective Clothing

This study reports process optimization studies of silica and zinc oxide-based flame-retardant (FR) coatings on cotton fabric for protective clothing and enhanced flammability properties. The experiments were designed by central composite design (CCD) using response surface methodology (RSM) to assess the synergistic protective effects of silica and zinc oxide FR coating. These prepared sols were coated on cotton fabrics by a simple dip dry cure process. The resulting FR-finished fabrics were characterized by SEM, mechanical properties, flame retardancy, and air permeability. SEM results confirmed the homogenous spreading of particles on cotton fabrics. From TGA results, it was noticed that the incorporation of silica and ZnO in the prepared nano-sols results in improved thermal stability of the FR-finished fabrics. These sol–gel-treated FR cotton fabrics showed excellent comfort properties, which shows their suitability for fire-retardant protective clothing. RSM analysis proved that the predicted values are in good agreement with the experimental values since R2 values for time to ignite, flame spread time, and air permeability were greater than 0.90. The optimized concentration of silica and ZnO in FR-finished fabrics was found to be 0.302% and 0.353%, respectively, which was further confirmed by confirmatory experiments. The optimization analysis successfully optimized the process for synergistic coating of silica and zinc oxide nanoparticles for enhanced flammability properties of FR cotton fabric for protective clothing.

Bio-based phytic acid/amino acid complex coating for antimicrobial and flame-retardant cotton fabrics

Here, a novel multifunctional coating containing bio-based phytic acid (PA), L-glutamic acid (L-Glu), and trimesoyl chloride (TMC) is constructed by a simple soaking strategy, giving cotton fabrics excellent flame retardancy, washability, and antibacterial properties. The coating layer on the cotton surface was prepared via the electrostatic and hydrogen bonding between PA and L-Glu, accompanied by the interface polymerization between PA, L-Glu, and TMC. Among them, the limiting oxygen index value of the treated cotton fabrics (C2 and C2-TMC) was as high as 40 %. During the vertical flammability test, both C2 and C2-TMC cotton showed self-extinguished behavior with a short damaged length (≤50 mm). Remarkably, the LOI of C2-TMC sustained a high value (30 %) even after 300 laundering cycles, maintaining its self-extinguishing behavior in the vertical combustion test. Additionally, in the cone calorimetry test, peak heat release rate and total heat release of treated cotton were lower than control cotton. Surprisingly, after 30 or 60 laundering cycles, the C2-TMC cotton exhibited excellent antibacterial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans due to the continuous exposure of PA and L-Glu. Moreover, the coating layer on the cotton surface had little impact on the mechanical properties and feel of the fabric.

Construction of efficient and environmentally friendly bio-based flame retardant cotton fabric through layer by layer self-assembly of alkylammonium functional silsesquioxane/phosphorylated sodium alginate

As an important source of green cleaning flame retardants, bio-based materials have been widely studied by researchers. However, the development of efficient biobased flame retardants and convenient finishing methods was of great significance for the functional finishing of materials. Herein, a convenient and efficient flame retardant cotton fabric was prepared via layer by layer self-assembly (LbL) by alternating precipitation of a novel bio-based flame retardant phosphorylated sodium alginate (PSA) and alkylammonium functionalized siloxane (A-POSS). The effect of coating number on flame retardancy and thermal properties of coated cotton fabric was systematically studied. Thermogravimetric analysis (TGA) results showed that residual char contents of AP/PS-15BL under air and N2 atmospheres increased by 252.0 % and 225.2 %, respectively, compared with control cotton. In vertical flammability tests, both the AP/PS-10BL and AP/PS-15BL showed self-extinguishing behavior and successfully passed the UL-94 V-0 rating. More importantly, the LOI value of AP/PS-15BL was significantly increased to 35.0 % from 20.0 % of pure cotton fabric. Additionally, coated samples showed good mechanical properties and washable resistance. In CONE test, the peak heat release rate (PHRR) and total heat release rate (THR) of AP/PS-15BL decreased by 89.3 % and 49.3 % respectively, compared with control cotton. Therefore, this green and convenient flame-retardant finishing method has great application potential in the multi-functional finishing of cotton fabrics.

B/P/N flame retardant based on diboraspiro rings groups for improving the flame retardancy, char formation properties and thermal stability of cotton fabrics

Developing flame retardant cotton fabrics (CF) is crucial for minimizing the harm caused by fires to people. To improve the flame retardancy of CF, this paper has synthesized a novel flame retardant called diboraspiro tetra phosphonate ammonium salt (N-PDBDN). The structure of N-PDBDN has been analyzed using FT-IR and NMR. Treating CF with N-PDBDN can increase the limiting oxygen index (LOI) to 36.2 % with a weight gain of 10.1 %. Moreover, even after undergoing 50 laundering cycles (LCs), the LOI remains at 27.1 %, indicating good flame retardancy and durability. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) show the presence of P and N elements on N-PDBDN treated CF, suggesting successful bonding between N-PDBDN and cellulose. Thermogravimetric analysis (TGA) results demonstrate that the addition of N-PDBDN significantly enhances the thermal stability and carbon formation ability of CF. Furthermore, cone calorimetry tests reveal reduced heat release rates (HRR), prolonged time to ignition (TTI), and 38 % lower total heat release (THR) in CF treated with N-PDBDN compared with pure cotton. Finally, a potential flame retardant mechanism involving N-PDBDN is proposed. These findings indicate that incorporating an ammonium phosphate group into CF can effectively improve the flame retardancy and durability.

Enhancement of Flame Retardancy of Cotton Fabrics by Calcium Hypophosphite-Chitosan Solution Compound Silica Sol

To enhance the thermal stability and flame retardancy of cotton fabrics, a hybrid sol was prepared by using silica (SiO2) sol, calcium hypophosphite (CaHP) and chitosan (CS), then finished on the surface of cotton fabrics through dipping-baking (drying) method. The results show that the CaHP-CS and SiO2 are successfully attached to the cotton fabric surface. Remarkably, the limiting oxygen index (LOI) value of the CaHP-CS-SiO2@COT was 31.30 % ( the highest of all samples). In the cone calorimetry test (CCT), the study revealed that the CaHP-CS-SiO2@COT has the lowest peak heat release rate (PHPP), fire growth rate (FGR) and CO2/CO. Its flame retardancy is mainly enhanced by the SiO2 (provides a gel coating with dimensional structure to block the transmission of oxygen and heat, CaHP (promotes cotton cellulose to dehydrate and form aromatic chars) and CS (dilute gaseous products and cool down heated areas).

Synergism between α-amino acid-derived polyamidoamines and sodium montmorillonite for enhancing the flame retardancy of cotton fabrics

Polyamidoamine (PAA)/sodium montmorillonite (MMT) nanocomposite coatings were investigated as flame retardants for cotton to ascertain whether the addition of clay improved the efficacy of PAAs thanks to its ability to act as insulating shield during combustion. Three amphoteric PAAs were obtained by reacting N,N’-methylenebisacrylamide with natural α-amino acids, namely glycine (M-GLY), arginine (M-ARG) and glutamic acid (M-GLU). These PAAs act as intumescent flame retardants for cotton performing well in horizontal flame spread tests (HFSTs) but failing to inhibit combustion in vertical flame spread tests (VFSTs). All three PAAs have been proven to form strong interactions in water with MMT via their protonated tert‑amine groups. The presence of 12.5 % MMT did not significantly change the thermal and thermo-oxidative stability of PAA coatings, while 2 % MMT add-on affected those of both untreated and PAA-treated cotton fabrics. In HFSTs, substituting 2 % MMT for PAA did not significantly change the flame retardant efficacy of the coatings. In VFSTs, the 2 % MMT/14 % PAA combination inhibited cotton ignition, regardless of the PAA structure, while in the 2 % MMT/11 % PAA combination M-GLU protected cotton from ignition, M-ARG extinguished the flame and M-GLY burned completely. By further reducing the PAA content to 8 %, only M-GLU quenched cotton combustion, leaving an RMF of 82 %. The fact that neither MMT nor PAAs alone induced flame extinguishment at the same add-ons used in the adopted formulations suggests a synergistic behavior of MMT and PAAs.

Turn Waste into Treasure: Novel High-Efficiency, Reactive, and Sericin-Based Intumescent Flame Retardant for Cotton Fabrics

Turn Waste into Treasure: Novel High-Efficiency, Reactive, and Sericin-Based Intumescent Flame Retardant for Cotton Fabrics

Multifunctional flame-retardant cotton fabric with hydrophobicity and electrical conductivity for wearable smart textile and self-powered fire-alarm system

The domain of smart textiles represents a widely researched area, showcasing promising prospects. Herein, a multifunctional smart textile (CF@PM-AA) has been designed and fabricated, amalgamating flame retardancy, electrical conductivity, and hydrophobicity into a unified entity. The flame retardant, synthesized through the reaction between amino trimethylene phosphonic acid and allantoin, was impregnated into cotton fabric through a facile impregnation method. Through surface modification with polydimethylsiloxane and multi-walled carbon nanotubes, the obtained CF@PM-AA acquires exceptional hydrophobic and acid-base environment durability. Significantly, the electrical conductivity of CF@PM-AA is greatly enhanced, with a reduced resistance down from 15.9 GΩ to 13 MΩ. Based on their electrical characteristics, the copper sheet and CF@PM-AA function as the electrode and friction layers, respectively, in the construction of the triboelectric nanogenerator. This configuration produces a voltage output of up to 125.6 V at a frequency of 4 Hz. Given its outstanding flame retardancy, hydrophobicity, and electrical performance, CF@PM-AA can be integrated into firefighting suits to establish a fire-alarm system with remote signal transmission function, enhancing personnel safety. Simultaneously, the CF@PM-AA holds promise for diverse applications in wearable flame-retardant and fire-alarm systems, opening new avenues for smart textile utilization in the Internet of Things domain.

Silica-Containing Phosphorus-Based Sol-Gel Finishing to Improve Flame Retardant Performance of Cotton Fabrics

In this paper, the sol-gel technique was used to design hybrid phosphorus-doped silica structures for improving the thermal stability and flame retardancy of cotton fabrics. To this aim, diethylphosphatoethyltriethoxysilane (DPTS) was employed as phosphate alkoxysilane in a multistep procedure that involved multiple layers (from 1 to 6) depositions. The multi-layer coatings were applied by padding using sols containing appropriate molar ratios of the precursor, anhydrous ethanol, catalyst, and hydrochloric acid. Moreover, the synergism P-N on flame retardancy of cotton was assessed by introducing 3-aminopropyltriethoxysilane (APTES) as an N-donor precursor in DPTS sols. The effects of the catalyst during the alkoxide reaction and the silica amount applied by sol-gel treatment on the thermo-oxidative behavior of the treated fabrics were deeply studied. The creation of the silica skeleton on the cotton surface and the interactions between the cellulosic fibres and the doped layer were investigated using FT-IR ATR spectroscopy. Moreover, thermal and thermo-oxidative stability, flammability properties, and combustion behavior of the sol-gel treated cotton fabrics were also studied, proving the effectiveness of the sol-gel coating in the fire protection of the cellulosic substrate.

Preparation and characterization of durable flame retardant cotton fabrics using phosphorylation reaction of cellulose with ammonium etidronate

Preparation and characterization of durable flame retardant cotton fabrics using phosphorylation reaction of cellulose with ammonium etidronate

A multifunctional flame-retardant TA-MXene based nanocoating for cotton fabric

Ti3C2Tx (MXene) is an ideal thermoelectric responsive fire-warning material but subject to its poor anti-oxidation and unsatisfied flame-retardant efficiency. Herein, a novel tannic acid (TA) decorated MXene (TA-MXene) with good anti-oxidation was fabricated and then used to prepare multifunctional flame-retardant cotton fabric (MFR@CF) combined with antimony potassium tartrate and polydimethylsiloxane. MFR@CF exhibited temperature-sensing and fire-warning performance. Moreover, MFR@CF showed superior flame retardancy with limiting oxygen index of 29 %. In addition, MFR@CF also possessed good thermal camouflage and self-cleaning performance, showing great application prospect in intelligent clothing and firefighting. Our work provides a new insight for preparing multifunctional smart firefighting CF.

A durable coating constructed by metal-organic framework and polyphosphazene for flame retardant cotton fabric with enhanced mechanical properties

The extremely flammable cellulose macromolecules in cotton fabrics seriously affect their application in the field of flame retardancy. In this paper, the surface of cotton fabric was modified with citric acid, and then metal-organic framework (UiO-66), cationic starch (St) and polyphosphonitrile (PZS) microspheres containing the transition metal element Zr were sequentially deposited to prepare an efficient and economical cotton fabric. St-PZS double-impregnated cotton fabrics have better thermal stability, flame retardancy and mechanical properties. And the coating does not affect the whiteness and stiffness of the cotton fabric. The results of thermogravimetric analysis showed that cotton/UiO-66/2St-PZS had a higher residual char rate (25.34%) under N2 atmosphere, which was 200.1% higher than that of control cotton (8.28%). In addition, cotton/UiO-66/2St-PZS had a 46.6% reduction in peak heat release, a 31.7% reduction in total heat release, and a 35.3% reduction in the peak of CO2 production compared to control cotton. It is worth noting that the average gross calorific value is 63.3% lower than that of the control cotton, indicating that flame retardant cotton fabrics can effectively inhibit the production of flammable gases. In addition, the tensile strength and elongation at break of cotton/UiO-66/2St-PZS are 458.79 N and 11.04%, respectively. After 20 laundering cycles, the mechanical properties remained almost unchanged.

Preparation and properties of stainless steel filament/pure cotton woven fabric

Abstract The flame-retardant cotton fabric used for welding protective clothing in the market exhibits insufficient melt hole resistance. We evaluated the stainless steel filament fabric for flame retardancy and melt hole resistance and found that it lacked sufficient comfort. A stainless steel filament and a cotton yarn were plied and twisted together and then woven following a set of specifications. The fabric was finished with a flame retardant, and its performance and flame retardancy were determined. The results indicate that the twist direction during ply twisting affects the fabric performance. Relative to the pure cotton fabric, the stainless steel filament/cotton composite fabric exhibits reduced comfort properties, such as moisture permeability and air permeability, but the mechanical properties and flame retardancy are improved. Ply twisting a stainless steel filament and a pure cotton yarn with an S twist presents certain advantages in enhancing the comprehensive performance of the fabric and exhibits potential for advancements in welding protective clothing.

A cationic, durable, P/N-containing starch-based flame retardant for cotton fabrics

A cationic, durable flame retardant for cotton fabrics, 6-(2-(dimethoxy phosphoryl)-2-(trimethyl ammonium)) methoxy-2-methoxy-polysaccharide ammonium phosphate (DTPAP), was synthesized. Its structure was verified by NMR and FTIR spectroscopy. According to the FTIR spectra and X-ray photoelectron spectroscopy (XPS), DTPAP formed P(=O)-O-C bonds with cellulose molecules and firmly grafted to cotton fabrics, giving the fabric a high durability. DTPAP-25-treated fabrics passed the vertical flame test (VFT), and the limiting oxygen index (LOI) was 43.9 %. After 50 laundering cycles (LCs), the DTPAP-25-treated fabrics had an LOI of 29.9 %, passed the VFT, and retained their flame retardancy. EDS data showed that, compared with engrafted cationic ammonium phosphate flame retardants, the DTPAP-treated fabrics contained fewer metal ions. Cone calorimetry data showed that DTPAP-25-treated fabrics did not display concentrated heat release. The results suggested that DTPAP exhibited a condensed-phase flame retardant mechanism, and the introduction of cations into the ammonium phosphate flame retardant reduced ion exchange, which improved the durability.

Fabrication of sustainable flame retardant cotton fabrics via foam finishing with sodium polyborate

The conventional process of imparting flame retardancy to cotton fabrics requires the consumption of large amounts of water, chemicals, and energy, which usually involves halogen-containing and phosphorus-containing chemicals. In this work, an eco-friendly sodium polyborate (SPB) foam was creatively introduced onto the cotton fabric surface by a bladed coater to improve the fire resistant performance. For the cotton sample with only 6.7% weight gain (WG) of SPB coating, the LOI value of cotton fabric (SPB treated cotton-1) was enhanced to 32.6% from 18.5%, the damaged length was decreased to 5.7 cm, and the sample self-extinguished in the vertical burning test. The peak of heat release rate value, total heat release value, and total smoke production (TSP) value decreased by 87.0%, 72.7%, and 22.2% respectively compared with those of the control sample. The TSP was further decreased by 80.6% when the WG of SPB was 16.7%. Besides, the SPB treated cotton showed enhanced antibacterial activities against S.aureus and E.coli. Particularly worth mentioning is in the SPB foam finishing procedure, no organic solvent and P or Cl-containing chemicals were involved, and the processing time was only around 3 min with obviously reduced water consumption, compared with dip-padding finishing. More importantly, SPB treated cotton kept good softness, whiteness, water vapor permeability, and air permeability. The SPB foam finishing in this work shows considerable potential in realize good flame retardancy on cotton fabrics by eco-friendly and high-efficient strategy.

Preparation and Application of a B/P/N Synergistic Flame Retardant for Cotton Fabric

Preparation and Application of a B/P/N Synergistic Flame Retardant for Cotton Fabric

A durable phosphorous-based flame retardant containing double reactive groups for cotton fabrics

Ammonium acryloyl phosphite (AAP) flame retardant with multiple reactive functional groups has been synthesized for use in cotton textiles. Nuclear magnetic resonance was utilized to analyze the structure of AAP flame retardant. The scanning electron microscopy images indicated that some flame retardants penetrated the amorphous region of cotton fibres. The energy-dispersive X-ray and Fourier transform infrared (FTIR) spectroscopy spectra suggested that AAP flame retardant was grafted with cellulose through forming the -N-P(=O)-O-C- connection. The laundering cycles (LCs), limiting oxygen index (LOI), cone calorimetry, and vertical flame test (VFT) suggested that AAP-treated cotton (CF/AAP) possessed exceptional flame retardance and durability. The CF/AAP3 demonstrated an initial LOI value of 47.2 %, which remained at 40.7 % even after undergoing 50 LCs following the washing standard (AATCC 61–2013 3A). The thermogravimetric and infrared spectroscopy, thermogravimetric, and VFT analyses showed that AAP grafting groups underwent a condensed-phase flame retardance mechanism. The X-ray diffraction patterns indicated that the AAP flame retardant affected the diffraction peak structure of cotton fibres crystal a little during the finishing process. After finishing, the cotton fabrics retained their breaking strength and softness effectively. The overall results indicated that incorporating reactive groups such as -N-P(=O)-(ONH4)2 and CH2CH- into flame retardants could reinforce the durability of flame-retardant cotton fabrics.

Multi-functionalization of cotton fabrics with excellent flame retardant, antibacterial and superhydrophobic properties

Cotton fabric is widely used in many fields for its excellent comfortability, breathability and hygroscopicity. However, the development of multifunctional cotton fabrics to meet the requirements of different scenarios is a top priority. In this study, multifunctional coating was constructed through facile layer-by-layer assembly phytic acid and chitosan, and spraying divalent copper ion and polydimethylsiloxane (PDMS) on cotton fabrics, anticipating to endow them with flame retardancy, antibacterial and superhydrophobic properties simultaneously. The treated cotton fabric achieved a limiting oxygen index (LOI) value of 32 %, with the char length reducing to 10.7 cm revealing excellent flame retardancy. The water contact angle of multifunctional treated cotton fabric was above 150°, demonstrating it had superhydrophobicity. The antibacterial rates of multifunctional cotton fabrics against E. coli and S. aureus reached to higher than 99 %, indicating that the excellent antibacterial properties. Combined with the thermal stability of cotton fabrics and their char residues analysis, these results demonstrated that the multifunctional coating could act through intumescent flame retardant mechanism to flame retardant cotton fabrics. This research provides a facile way to prepare multifunctional cotton fabrics to broaden the application prospect.

Aqua‐mediated in situ synthesis of highly potent phosphorous functionalized flame retardant for cotton fabric

AbstractFlame retardancy in various materials is becoming an increasingly important performance feature. In the textile industries, fire‐related problems have become an important concern over the decade. Herein, the polyvinyl alcohol (PVA) and graphene‐supported material were functionalized with trimethyl phosphate (TMP) for the synthesis of flame retardant (FR) composite material [graphene polymer functionalized trimethyl phosphate (GPTMP)] in the aqueous medium, which improves the stability of cotton fabric against flame. Graphene and PVA fabricated with phosphorus functional groups make the fabric more comfortable against fire and help to avoid further spreading of fire. The composite‐coated fabric sustains for a long time on continuous flame with maintaining its initial shape and size. The GPTMP‐coated fabric shows flame retardancy for up to 540 s on constant flame exposure, whereas control samples such as PVA‐, graphene oxide‐, and TMP‐coated fabrics resist for up to 15, 20, and 14 s, respectively. The limiting oxygen index (LOI) and vertical flammability test (VFT) for synthesized composites were performed to confirm and support the flame retardancy property of GPTMP. The GPTMP shows the 35% LOI value and forms the char length of 2.6 cm during VFT. This work provides a simple and eco‐friendly method to obtain novel GPTMP, which has a high potential as a FR for different fabrics, including cotton.

Influences of boron and nitrogen co-doped carbon dot based coating fabricated via layer-by-layer self-assembly on the UV protection and flame retardancy of cotton fabric

Influences of boron and nitrogen co-doped carbon dot based coating fabricated via layer-by-layer self-assembly on the UV protection and flame retardancy of cotton fabric