Flame retardant finishing of the polyester/cotton blend fabric using a cross‐linkable hydroxy‐functional organophosphorus oligomer

Blend fabrics of cotton and polyester are widely used in apparel, but high flammability becomes a major obstacle for applications of those fabrics in fire protective clothing. The objective of this research was to investigate the flame retardant finishing of a 50/50 polyester/cotton blend fabric. It was discovered previously that N,N′‐dimethyloldihydroxyethyleneurea (DMDHEU) was able to bond a hydroxy‐functional organophosphorus oligomer (HFPO) onto 50/50 nylon/cotton blend fabrics. In this research, the HFPO/DMDHEU system was applied to a 50/50 polyester/cotton twill fabric. The polyester/cotton fabric treated with 36% HFPO and 10% DMDHEU achieved char length of 165 mm after 20 laundering cycles. The laundering durability of the treated fabric was attributed to the formation of polymeric cross‐linked networks. The HFPO/DMDHEU system significantly reduced peak heat release rate (PHRR) of cotton on the treated polyester/cotton blend fabric, but its effects on polyester were marginal. HFPO/DMDHEU reduced PHRR of both nylon and cotton on the treated nylon/cotton fabric. It was also discovered that the nitrogen of DMDHEU was synergistic to enhance the flame retardant performance of HFPO on the polyester/cotton fabric.     

Flame retardant finishing of cotton fleece fabric. II. Inorganic phosphorus‐containing compounds

Cotton fleece is not able to meet the federal flammability standard for general apparels (CFR 1610) without flame retardant treatment. Consequently, cotton fleece is not available in the market in spite of high demands. In our previous research, we studied the application of a hydroxyl‐functional organophosphorus oligomer as a flame retardant finishing agent for cotton fleece. In this research, we investigated the use of aluminum hydroxyphosphate (AHP) formed in situ on cotton by the reaction of aluminum sulfate and sodium phosphates to reduce the flammability of cotton fleece. We found that the AHP formed on cotton is effective in reducing the cotton fleece's flammability from “Class 3” to “Class 1.” Elemental analysis of aluminum and phosphorus in the AHP shows that the mole ratio of Al/P changes as the pH value of the sodium phosphates solution changes. The pH of the sodium phosphate solutions also affect the quantity of AHP formed on the cotton fleece. The treated cotton fleece retains “Class 1” flammability after one home laundering or the combination of dry‐cleaning and hand washing procedures. The treatment increases the whiteness of the cotton fleece whereas it reduces its bursting strength. The cotton fleece thus treated is also investigated using differential scanning calorimetry and scanning electron microscopy. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Flame retardant finishing of cotton fleece fabric: Part V. Phosphorus‐containing maleic acid oligomers

The high flammability of cotton fleece makes it necessary to apply a flame retardant system on cotton fleece so that it can meet the federal regulation ‘Standard for the Flammability of Clothing Textiles’ (16 CFR 1610). The objective of this research was to reduce the flammability of cotton fleece using the phosphorus‐containing maleic acid oligomers (PMAO) synthesized by aqueous free radical polymerization of maleic acid. We found that PMAO can be bound to cotton fleece by esterifying with cotton cellulose with sodium hypophosphite as the catalyst. Both the 45^° flammability and limiting oxygen index data indicated that the treatment of cotton using PMAO reduced the flammability of cotton fleece. The micro‐scale combustion calorimetric data revealed that PMAO reduced the peak heat release rate and heat release capacity of the treated cotton woven fabric. The cotton fleece treated with PMAO/NaH₂PO₂ passed the federal flammability test (16 CFR Part 1610) and achieved ‘Class 1’ flammability. The PMAO bound to cotton was durable to multiple home laundering cycles. The treated fleece also showed high strength retention with little change in fabric whiteness. The use of triethanolamine as an additive modestly enhanced the performance of PMAO with no significant changes in fabric physical properties. Copyright © 2009 John Wiley & Sons, Ltd.     

Correlation between limiting oxygen index and phosphorus/nitrogen content of cotton fabrics treated with a hydroxy‐functional organophosphorus flame‐retarding agent and dimethyloldihydroxyethyleneurea

The combination of a hydroxyl‐functional organophosphorus flame‐retarding agent (FR) and dimethyloldihydroxyethyleneurea (DMDHEU) was used as a durable flame‐retardant finish system for cotton fabrics. DMDHEU functions as a binder between FR and cotton cellulose, thus making this flame‐retarding system durable to home laundering. DMDHEU also provides nitrogen to this system, therefore enhances its performance. Limiting oxygen index (LOI) is one of the most commonly used parameters to indicate the flammability of textiles and other polymeric materials. In this research, we investigated the correlation between LOI and phosphorus/nitrogen content on the cotton fabric treated with that durable flame‐retardant system. Phosphorus concentration on the fabric was analyzed by inductively coupled plasma atomic emission spectroscopy, whereas the nitrogen content was determined indirectly by measuring the carbonyl band intensity in the infrared spectra of the treated fabric. We developed a statistical model to predict LOI of the cotton fabric treated with FR and DMDHEU based on the phosphorus concentration and the intensity of carbonyl band of DMDHEU on cotton. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1885–1890, 2003     

Effect of chicken‐feather protein‐based flame retardant on flame retarding performance of cotton fabric

A new kind of eco‐friendly chicken‐feather protein‐based phosphorus–nitrogen‐containing flame retardant was synthesized successfully with chicken‐feather protein, melamine, sodium pyrophosphate, and glyoxal. And its structure was characterized by Fourier transform infrared spectroscopy, and the thermogravimetry of the agent was analyzed. Then the flame retarding performances of the chicken‐feather protein‐based flame retardant and in combination with the borax and boric acid in application to a woven cotton fabric were investigated by the vertical flammability test and limited oxygen index test. In addition, the surface morphologies of the treated and untreated fabrics were conducted by the scanning electron micrographs (SEM), and the thermogravimetric analyses of the treated and untreated cotton were explored, and the surface morphologies of char areas of the treated and untreated fabrics after burnt were tested by the SEM. The results showed that the flame retardancy of the cotton fabric treated by the chicken‐feather protein‐based flame retardant in combination with borax and boric acid was improved further, and the combination of the chicken‐feather protein‐based flame retardant and borax and boric acid could facilitate to form a homogenous and compact intumescing char layer, and the combination of them plays a good synergistic effect in the improvement of the flame retardancy of the treated cotton fabric. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40584.     

Flame‐retardant finishing of cotton fabrics using polyamino carboxylic acids and sodium hypophosphite

The purpose of this research was to use polyamino carboxylic acids (PACAs) and their combination with sodium hypophosphite (NaH₂PO₂) as a flame‐retardant finishing system for cotton fabrics. Flammability of cotton fabric was evaluated by 45° flammability test, differential scanning calorimetry and measuring the char yield. The combination of polyamino carboxylic acids and sodium hypophosphite as a phosphorus‐containing catalyst reduces the flammability of cotton. The pyrolysis properties and the results of char yield of the finished cotton show that with increasing amount of catalyst, the flame retardancy increases. Fastness against multiple laundering, whiteness and tensile strength of the cotton finished with PACAs/NaH₂PO₂ to multiple standard laundering have been studied, too. The flame retardancy effect has an acceptable washing fastness. Whiteness and tensile strength of the finished cotton do not change significantly. Copyright © 2012 John Wiley & Sons, Ltd.     

Graft copolymerization of nitrogen‐ and phosphorus‐containing monomers onto cellulosics for flame‐retardant finishing of cotton textiles

Phosphoramide containing an active vinyl group (P‐III) was prepared. Its structure was confirmed by elemental analysis and Fourier transform infrared, nuclear magnetic resonance, and mass spectroscopy. P‐III was evaluated as a fire‐retardant finishing agent for cotton fabrics. It was applied to cotton fabrics using a graft process with an Fe²⁺/H₂O₂ redox system. The major factors affecting the reaction were studied. The finished cotton fabrics were examined for flammability, and the effect of washing on treated fabrics was also examined. The results showed that P‐III can be successfully used as a flame retardant for cotton fabrics. Durably flame‐retardant cotton fabrics were obtained at add‐on levels higher than 38%. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2573–2578, 2003     

Improvement in the flame retardancy of cotton fabric by admicellar polymerization of 2‐acryloyloxyethyl diethyl phosphate using an anionic surfactant

The phosphorus‐containing acrylate monomer, 2‐acryloyloxyethyl diethyl phosphate (ADEP), was synthesized and applied to cotton fabric by using admicellar polymerization. Sodium dodecylbenzene sulfonate was used as the anionic surfactant. The film of polymerized monomer (PADEP) formed on the cotton surface was characterized by FTIR‐ATR spectroscopy and SEM. Thermal and flame retardant properties of PADEP‐coated cotton were investigated by TGA and flammability tests. Results showed that PADEP polymer film was successfully formed on the cotton fabric. The TGA and DTG analyses showed that the phosphorus‐containing PADEP lowered the decomposition temperature of the treated fabric resulting in a higher char yield than in the case of untreated cotton. The flammability tests showed that the treated cotton had much improved flame retardancy property after the treatment. The treated fabric also retained its good pliability and soft touch with good air permeability. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Microintumescent mechanism of flame‐retardant water‐based chitosan–ammonium polyphosphate multilayer nanocoating on cotton fabric

Layer‐by‐layer (LbL) assembly of nanocoatings on fabric substrates has been very successful in terms of reduction of flammability. In particular, an LbL system comprised ammonium polyphosphate as the polyanion and chitosan as the polycation, applied to cotton fabric, dramatically reduced cotton flammability. At this point, the fire‐retardant (FR) mechanism of action of this system has never been fully elucidated. Sonicated and nonsonicated coated cotton fabrics were evaluated using a vertical flame test and mass loss calorimeter. Coating morphology was investigated before and after burning. Thermal analyses and chemical analyses in the condensed phase (and in the gas phase) were conducted to reveal the FR mechanism of action. At the cotton surface, a combination of both condensed (formation of aromatic char) and gas phase (release of water and highly flammable gases) mechanisms impart the FR behavior, promoting a kind of “microintumescence” phenomenon. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43783.     

Flame‐retardant fabric systems based on electrospun polyamide/boric acid nanocomposite fibers

To examine the feasibility of developing flame‐retardant‐textile coated fabric systems with electrospun polyamide/boric acid nanocomposites, fiber webs coated on cotton substrates were developed to impart‐fire retardant properties. The morphology of the polyamide/boric acid nanocomposite fibers was examined with scanning electron microscopy. The flame‐retardant properties of coated fabric systems with different nanoparticle contents were assessed. The flame retardancy of the boric acid coated fabric systems was evaluated quantitatively with a flammability test apparatus fabricated on the basis of Consumer Product Safety Commission 16 Code of Federal Regulations part 1610 standard and also by thermogravimetric analysis. The 0.05 wt % boric acid nanocomposite fiber web coated on pure cotton fabric exhibited an increment in flame‐spreading time of greater than 80%, and this indicated excellent fire protection. Also, the coated fabric systems with 0.05% boric acid nanocomposite fiber webs exhibited a distinct shift in the peak value in the thermal degradation profile and a 75% increase in char formation in the thermooxidative degradation profile, as indicated by the results of thermogravimetric analysis. The results show the feasibility of successfully imparting flame‐retardant properties to cotton fabrics through the electrospinning of the polymer material with boric acid nanoparticles. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and application of a sulfur‐containing phosphoric amide flame retardant for nylon fabric

A sulfur‐containing flame retardant (SFR) was synthesized from polyphosphoric acid, epoxy chloropropane, and thiourea. Using a water‐soluble isocyanate‐terminated (WIT) cross‐linker, the flame retardant was applied as a flame‐retardant finishing on nylon fabric. WIT is a compound that not only cross‐links SFR and nylon cellulose but also contains no formaldehyde. Comparisons of the main performances of SFR with those of N‐methyloldimethylphosphonopropionamide (known as ‘Pyrovatex CP’) and a bicyclic phosphonite (known as ‘Antiblaze 19T’) indicate that the presence of sulfur in SFR plays a crucial role in decreasing the flammability of the nylon fabric. The limiting oxygen index value and damaged carbon length of the finished nylon fabric were 29.4% and 5.7 cm, respectively, when the concentrations of SFR and WIT were 200 and 40 g/L, respectively, and the baking temperature and time were 150 °C and 3 min, respectively. After 10 laundry cycles, the fabric still retains some flame retardancy. Copyright © 2016 John Wiley & Sons, Ltd.     

A novel halogen‐free and formaldehyde‐free flame retardant for cotton fabrics

A novel halogen‐free and formaldehyde‐free flame retardant (FR), which contains phosphorus, nitrogen, and silicon, was synthesized for cotton fabrics considering the synergistic effect of phosphorus, nitrogen, and silicon. The structure of the new FR was characterized by Fourier‐trans‐form infrared spectroscopy, and the surface morphology of the treated fibre was observed using scanning electron microscope. The thermal property of the FR treated cotton fabric was studied through thermal gravimetric analysis. The TG results indicate that the FR can protect cotton fabric from fire to a certain degree. The vertical flammability test and limiting oxygen index results further indicate that the FR has excellent FR properties. Finally, the durability and other performance properties of the treated fabric were studied and the results show that the new materials can be used as a semi‐durable FR for cellulosic fibres. Copyright © 2011 John Wiley & Sons, Ltd.     

Thermal properties and combustion behavior of POSS‐ and bohemite‐finished cotton fabrics

A finishing process with polyhedral oligomeric silsesquioxane (POSS) and bohemite nanoparticles has been exploited for enhancing the thermal stability and flame retardancy of cotton fabrics. The thermal behavior of flame retardant treated cellulosic fabric has been studied by thermogravimetric analyses (TGAs). It has been found that such nanoparticles favor the carbonization of the cellulose and slow down the kinetics of thermo‐oxidation in air. At the same time, the finished fabrics have turned out to be more efficient with respect to neat cotton as far as the flame retardancy is concerned, pointing out an increase of the time to ignition (TTI) and a decrease of the heat release rate (HRR). Furthermore, a comparison between the fire performances of the nanoparticles under study and a commercial phosphorus‐based flame retardant has been investigated. The morphology and elemental composition present in the treated fabrics have been also investigated using scanning electron microscopy (SEM) coupled to the energy dispersive spectroscopy (EDS), and the results have been compared with the untreated fabric. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Layer‐by‐layer assembly of halogen‐free polymeric materials on nylon/cotton blend for flame retardant applications

Thin films of environmentally safe, halogen free, anionic sodium phosphate and cationic polysiloxanes were deposited on a Nyco (1:1 nylon/cotton blend) fabric via layer‐by‐layer (LbL) assembly to reduce the inherent flammability of Nyco fabric. In the coating process, we used three different polysiloxane materials containing different amine groups including, 35–45% (trimethylammoniummethylphenythyl)‐methyl siloxane‐55‐65% dimethyl siloxane copolymer chloride salt (QMS‐435), aminoethylaminopropyl silsesquioxane‐methylsilsesquioxane copolymer oligomer (WSA‐7021) and aminopropyl silesquioxane oligomers (WSA‐991), as a positive polyelectrolyte. Thermo‐gravimetric analysis showed that coated fabric has char yield around 40% at 600 °C whereas control fabric was completely consumed. The vertical flame test (VFT) on the LbL‐coated Nyco fabric was passed with after flame time, 2 s, and the char length of 3.81 cm. Volatile and nontoxic degradation products of flame retardant‐coated fabric were analyzed by pyrolysis gas chromatography mass spectroscopy (Py‐GCMS). Surface morphology of coated fabrics and burned fabric residues were studied by scanning electron microscopy. Copyright © 2014 John Wiley & Sons, Ltd.     

Flame‐retardant finishing in cotton fabrics using zinc oxide co‐catalyst

In this article, N‐Methylol dimethylphosphonopropionamide (FR) in combination with a melamine resin (CL), phosphoric acid (PA) catalyst and zinc oxide (ZnO) or nano‐ZnO co‐catalyst were used (FR‐CL‐PA‐ZnO or nano‐ZnO system) to impart flame‐retardant property on cotton fabrics. FR‐CL or FR‐CL‐PA‐treated cotton specimen showed roughened and wrinkled fabric surface morphology, which was caused by the attack of the FR with slightly acidity. In addition, FTIR analysis showed some new characteristic peaks, carbonyl, CH₂ rocking and CH₃ asymmetric and CH₂ symmetric stretching bands, in the chemical structure of treated cotton specimens. Apart from these, the flame ignited on the flame‐retardant‐treated fabrics (without subjected to any post‐wet treatment) extinguished right after the removal of ignition source. However, FR‐CL treated specimens were no longer flame‐resistant when the specimens subjected to neutralization and/or home laundering, while FR‐CL‐PA treated specimens showed opposite results. By using 0.2% and 0.4% of ZnO or nano‐ZnO as co‐catalyst, the flame spread rate of neutralized and/or laundered test specimens decreased, even the specimens were undergone 10 home laundering cycles. Moreover, flame‐retardant‐treated cotton specimens had low breaking load and tearing strength resulting from side effects of the crosslinking agent used, while addition of ZnO or nano‐ZnO co‐catalyst could compensates for the reduction. Furthermore, the free formaldehyde content was dropped when ZnO and nano‐ZnO co‐catalyst was added in the treatment. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

A facile one‐step synthesis of flame‐retardant coatings on cotton fabric via ultrasound irradiation

This article reports a facile one‐step methodology to increase fire resistance properties of cotton fabric. The flame‐retardant coating for cotton fabric was synthesized with methyltriethoxysilane and organophosphates (M102B) through an ultrasound irradiation process. The coating structure and surface morphology of uncoated and coated fabrics were investigated by Fourier transform infrared spectroscopy and scanning electron microscope, respectively. The flame‐retardant properties, bending modulus, air permeability and thermal stability were studied by vertical burning test, cantilever method, air permeability test and thermogravimetric analysis (TGA). As a result, the cotton fabric coated with 29.2% (mass increased) of flame‐retardant coating was able to balance the flame retardant property and wearing comfort of the fabrics. The TGA results showed that the residue char of cotton was greatly enhanced after treatment with the coating, which has a high char forming effect on cellulose during testing. Furthermore, flame‐retardant property of coated fabrics did not change significantly after 10 washing cycles. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45114.     

Effect of titanium dioxide on the flame‐retardant finishing of cotton fabric

In this study, titanium dioxide (TiO₂) or nano titanium dioxide (nano‐TiO₂) was used as a cocatalyst in the flame‐retardant (FR) formulation of N‐methylol dimethylphosphonopropionamide (Pyrovatex CP New, FR), melamine resin [Knittex CHN, crosslinking agent (CL)], and phosphoric acid (PA) for cotton fabrics to improve the treatment effectiveness and minimize the side effects of the treatment. For FR‐treated cotton fabrics, the flame extinguished right after removal of the ignition source with no flame spreading. However, after neutralization and/or home laundering, FR–CL‐treated specimens failed the flammability test, whereas the opposite results were obtained from FR–CL–PA‐treated specimens. A noticeable result was that the TiO₂/nano‐TiO₂ cocatalyst had a significant effect on decreasing the flame‐spread rate. Thermal analysis found that the FR‐treated specimens without wet posttreatment showed two endothermic peaks representing the phosphorylation of cellulose and acid‐catalyzed dehydration. In addition, the treated fabrics showed some new characteristic peaks in their chemical structures; these were interpreted as carbonyl bands, CH₂ rocking bands, and CH₃ asymmetric and CH₂ symmetric stretching. The surface morphology of the FR–CL–PA‐treated cotton specimens showed a roughened and wrinkled fabric surface with a high deposition of the finishing agent that had a lower breaking load and tearing strength, which resulted from the side effects of the CL used. However, the addition of a TiO₂ or nano‐TiO₂ cocatalyst could compensate for the reduction in the tensile strength. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Flame‐retardant properties of soybean fabric modified with N‐methylol diakyl phosphonopropionamide

Soybean is a competitive production material for fibers as it is abundant and cost effective. However, an inherent deficiency of soybean fiber is its poor flame‐retardant performance. In this study, the effect of N‐methylol diakyl phosphonopropionamide (Pyrovatex CP) on the flame retardancy of soybean was investigated by the Limiting Oxygen Index (L.O.I.) and the vertical flammability test. Little benefit with regard to flame retardancy was found when soybean was treated with Pyrovatex CP in the absence of additives. However, the incorporation of Lyofix MLF in the finishing treatment (3% w/v) increased the L.O.I. values of soybean fiber and enhanced char formation as indicated by Thermogravimetric Analysis (TGA). Improved fastness to washing was observed at higher application levels of Lyofix MLF (6% w/v). X‐ray Photoelectron Spectroscopy (XPS) indicated that surface phosphorus (% atomic) was reduced following washing for all fabrics examined. In addition, the substantivity of Lyofix MLF to soybean surface was exhibited. The flame‐retardant treatment presented in this article is cost effective and results in wash‐durable flame‐retardant fabrics. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Antiwrinkle treatment of cotton fabric with a mixed sol of TEOS‐TTB/DMDHEU

This research explored the effect of a mixed sol on the physical properties of a treated fabric, and confirmed the crosslinkage of SiO₂ and dimethyloldihydroxyethyleneurea (DMDHEU) using Fourier transform infrared(FTIR) spectroscopy and nuclear magnetic resonance (NMR). In the experiment, DMDHEU was applied to a cotton fabric and different mole ratios of tetraethoxysilane (TEOS)/titanium (IV) n‐butoxide (TTB) were added. The mixture was then subjected to immersion, padding, drying, and curing. The results showed that hydrogen bonds had formed between SiO₂ and DMDHEU. The treated fabric had improved antiwrinkle properties, tensile‐strength retention, and yellowing degree when the mole ratio of TEOS was increased. By contrast, the softness of the fabric showed the opposite trend. When the mole ratio of TEOS/TTB was set at 10/1, the treated fabric showed a significant reduction of its antiwrinkle properties under both dry and wet conditions. The fabric treated with TEOS/TTB was superior to the traditionally treated fabric in terms of its ultraviolet (UV) light resistance. When the mole ratio of TEOS/TTB was 2.5/1 or 5.0/1, the addition of 10% DMDHEU during the treatment of the cotton fabric, followed by drying for 5 min at 80°C and curing at 150°C for 2 min, resulted in the fabric having improved and more balanced physical properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Lyocell非织造布的阻燃整理及其性能

针对Lyocell非织造布的易燃性问题,利用水性氨基树脂和自制植酸铵作为阻燃整理剂,采用浸轧-烘焙的工艺对Lyocell非织造布进行阻燃整理.通过傅里叶红外光谱仪、热重分析仪、扫描电子显微镜对阻燃整理Lyocell非织造布的红外特征、耐热稳定性、表面形貌进行表征与测试分析,并对阻燃整理Lyocell非织造布的极限氧指数...