Flame resistant cotton fabrics prepared by radiation-initiated polymerization with vinyl phosphonate oligomer and N-methylolacrylamide

Radiation-initiated polymerization of vinyl phosphonate oligomer (molecular weight 500–1000) and N-methylolacrylamide from aqueous solutions was investigated with cotton printcloth, flanelette, and sateen fabrics and with cotton (50%)–polyester (50%) flannelette fabrics. Determinations were made of the effects of radiation dosage, mole ratio of vinyl phosphonate in the oligomer to N-methylolacrylamide in aqueous solution, concentration of reactants, wet pickup of solutions on fabrics, and irradiation of both dry and wet fabrics on efficiency of conversion of oligomer and monomer in solution to polymer add-on. The effects of vinyl phosphonate oligomer and N-methylolacrylamide radiation-initiated polymerization on some of the textile properties of cotton printcloth and on flame resistances of cotton and cotton–polyester fabrics were evaluated. The breaking strength of modified cotton printcloth was about the same as that of unmodified fabric; however, the tearing strength and flex abrasion resistance of modified fabric were reduced. The textile hand of the modified printcloth fabrics that had flame resistance indicated: interaction between cellulose and vinyl phosphonate oligomer–poly(N-methylolacrylamide) and uniform deposition in the fibrous cross section (transmission electron microscopy); surface areas of heavy deposits of oligomer–polymer (scanning electron microscopy); and phosphorus located throughout the fibrous cross section (energy dispersive x-ray analysis). Polymerization of vinyl phosphonate oligomer and N-methylolacrylamide was radiation initiated with cotton–polyester fabric; however, this modified fabric did not have flame-resistant properties.     

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.     

Verification Concerning the Relative Superiority of a Cellulosic Fabric with Regard to Polyester in Terms of Flammability

In order to prove the superiority of cotton fabric to polyester with regard to flammability, we have studied the effect of Graham's salt as a moderate and nondurable finish on the flammability of pure polyester and cotton fabric. The laundered bone-dried, weighed fabrics were impregnated with suitable concentration of aqueous Graham's salt solutions by means of squeeze rolls and drying at 110°C for 30 min. They were then cooled in a desiccator, reweighed with analytic precision, and kept under ordinary conditions before the accomplishment of the vertical flame test. The optimum add-on value to impart flame retardancy was about 43.65% for polyester fabric and 36.78% for cotton fabric. The results obtained comply with the Coating Theory. Moreover, the superiority of cotton fabric to polyester fabric in terms of combustibility has been deduced.     

石墨烯微胶囊/海藻酸钙对涤纶织物的阻燃处理

为提高涤纶织物的阻燃性能,并解决涤纶织物的熔滴现象,本文采用石墨烯微胶囊与海藻酸钠共混制备出阻燃涂覆液,采用浸轧法制备阻燃涂覆涤纶织物。考察涂覆涤纶织物的阻燃性能,力学性能以及热学性能,结果表明：25g/L的海藻酸钠和1g的石墨烯微胶囊阻燃涂覆处理后的涤纶织物的极限氧指数由19.7%,上升到28.34%,达到难燃织物的标准。整理后的涤纶织物达到了V-0标准,涤纶织物燃烧后产生的熔滴的现象消失。织物的断裂强力由135.21N降低到了106.77N。涂覆处理前后,织物达到最大热分解速率的温度未产生明显变化,残炭率由12.07%上升到了26.98%,最大质量损失速率由1.79%/℃降低到了0.96%/℃。同时整理前后涤纶织物的热焓值由58.4J/g上升至68.4J/g。织物的导热系数由0.587 W/cm.℃×10_-4^提高到0.842W/cm.℃×10_-4^{,热学性能得到了充分的提高。}织物燃烧后所形成的残炭由无到连续且致密。     

Flame-retardant viscose–polyester fabrics

For many purposes the natural-synthetic fiber-blend fabrics are more suitable than pure natural or synthetic products. It is often possible to obtain a maximum in clothing and textile technical properties by compensating the defects of one fiber by using an other totally different fiber. Many problems, however, have arisen in the production of flame-retardent fabrics because the use of synthetic fibers often makes the fire retardancy less effective. In our 2-year research project different fire-retardant (FR) viscose–polyesters fabrics were prapared at first in the laboratory scale. The natural type raw materials were Modal Prima viscose and normal FR–viscose cotton type staple fibers. The synthetic raw materials were FR–polyesters of the same type with two different flame retardants. Test fabrics were knitted in the laboratory by using seven blended yarns in the ratios 100/0, 80/20, 65/35, and 50/50 and vice versa. Cotton type PVC–fiber was also used in some experiments. All these test fabrics were also finished chemically by using normal crease-resistant (DMU, DMEU, DMDHEU, and TMM) and flameretardant (N,-methylolphosphonopropionamide and THPC) finishing chemicals. The textile and fire-retardant properties of the original and finished fabrics were estimated by using addon, tensile strength, LOI-value, and vertical flame test determinations. The mechanism of flame retardancy was also studied with DSC technique, P- and N-analysis and char investigations. The test results of viscose/polyester studies were compared with the results of cotton/polyester studies. After laboratory studies the best methods for FR–viscose/polyester fabric production were chosen, and the fabrics were manufactured. The fabrics were home-washed 20–50 times, and the textile and FR-properties were determined after each 10 washings. These results were again compared with results of cotton/polyester fabrics.     

Synthesis of phosphorus-containing flame retardants and investigation of their flame retardant behavior in textile applications

Flame retardants are a growing area of research interest. Nonhalogenated, durable, and nonleachable flame retardants are one of the main strategies used in the research of flame retardant polymers. In this regard, the covalent attachment of phosphorus-containing flame retardants onto cotton fabric has been developed. Two types of reactive phosphorus-containing flame retardants (MKT-1 and MKT-2) have been synthesized and used as a surface coating for cotton fabric. MKT-1 possesses anhydride and acid functionalities that can react with the  OH functionalities in cellulose. In addition, MKT-2 has both acid and organosilicon groups that can also react with the hydroxy group present in cellulose. The structures of the reactive flame retardants (MKT-1 and MKT-2) were characterized using ¹³C and ³¹P nuclear magnetic resonance spectroscopy. Thermal properties of the coated and uncoated cotton fabrics were investigated using thermogravimetric analysis. Surface characterization was carried out using scanning electron microscopy and X-ray photoelectron spectroscopy. A standard test method used to evaluate the flammability of blankets (BS 5852) was also applied to characterize the fire retardant properties of the coated and uncoated cotton fabrics studied. Different loadings of MKT-1 and MKT-2 on the fabric (10, 20, and 30% by weight in dimethylformamide solution) were applied in the dip coating process. The cotton fabric coated with 30% MKT-2 does not burn after being subjected to a propane burner for 20 s and also produced the highest char yield (36%) at 500 °C. Inductively coupled plasma–optical emission spectrometry showed that MKT-1 contains 8.23 ± 0.33 P% whereas MKT-2 contains 3.88 ± 0.15 P%. Although MKT-1 possess a higher P content than MKT-2, the additive effect caused by the organosilicon and nitrogen groups present in MK-2 enhance its flame retardant properties. Furthermore, the covalently attached flame retardant materials are durable and do not hydrolyze during washing. The mechanical properties of coated fabrics were characterized by a tensile test and significant change in elongation at break was observed. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47935.     

Tear behavior of polyester‐based coated textiles after thermo‐oxidative aging

In this article, a new method to characterize the tear behavior of coated textiles using fracture mechanics is proposed. The energy dissipated in tearing (EDT) of as‐received and thermally aged samples of polyester fabric, polyvinyl acetate rubber coating, and textile‐coating composites was calculated and compared. The EDT of the coated fabric displayed a slightly smaller value than the fabric alone, whereas the EDT of the coating was found to be negligible when compared with the other two. The presence of the coating is believed to have a detrimental effect on the tearing behavior of the coated fabric as it hinders interfilament slippage. A master curve of EDT retention vs. aging time for noncoated and coated fabric samples was constructed using the time–temperature superposition principle and fitted using the Hill equation. Fourier transform infrared analyses carried out on aged fabric samples hinted at a possible chain scission process, whereas the crystallinity of fabric samples, calculated via differential scanning calorimetry, was found to decrease after thermal aging. Scanning electron microscopy images revealed an increase in surface roughness after aging that may reduce interfilament friction. These results, coupled to an increase in the adhesion strength between fabric and coating, are likely the cause of the reduction of EDT noticed in aged coated and noncoated fabrics compared with as‐received ones. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

A novel blowing agent polyelectrolyte for fabricating intumescent multilayer coating that retards fire on cotton fabric

Sulfonated melamine‐formaldehyde (SMF) resin was successfully synthesized with a mixture of formaldehyde, melamine, and NaHSO₃ in an aqueous solution. Then the SMF was used as the blowing agent to combine with chitosan and phytic acid for fabricating the intumescent flame retardant coating on the surface of the cotton fabric by layer‐by‐layer (LbL) self‐assembled technology. As characterized by X‐ray photoelectron spectroscopy, scanning electron microscopy, and attenuated total reflection Fourier transform infrared spectroscopy, the (chitosan/SMF + phytic acid)_n coating was successfully deposited on the surfaces of cotton fibers. Thermogravimetric analysis results exhibited that the thermal stabilities of coated cotton fabrics under nitrogen and air atmosphere were enhanced at temperatures ranging from 400 to 700 °C compared with pure cotton fabric. At 700 °C, the char residues of cotton‐5BL and cotton‐10BL under a nitrogen atmosphere were improved 25.9 and 32 wt % than that of pure cotton fabric, respectively. In the vertical flame test, the self‐extinguishing could be obtained for the cotton‐10BL sample. This work first utilized SMF as negative polyelectrolyte to fabricate intumescent flame retardant coating by LbL self‐assembled technology on cotton fabric to strengthen its thermal stability and flame resistance. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46583.     

Flame-resistant polyester/cotton fabrics

New experimental results are reported for the modification of 50/50 polyester/cotton blend fabrics made from bromine-free and bromine-containing polyester with a reactive flame retardant compound of high phosphorus content. Reaction of the cotton in the blend with methyl-phosphonic diamide yields modified fabrics in which flame resistance is attained without impairment of fabric hand. The level of flame resistance depends on the amount of insolubilized phosphorus in the treated fabric, but the hand is essentially unchanged even for fabrics of high phosphorus content which pass the vertical test of DOC-FF-3-71. The results of this work provide a basis for improved definitions of future approaches to the development of flame resistant polyester/cotton blend fabrics.     

Surface modification of polyester and polyamide fabrics by low frequency plasma polymerization of acrylic acid

In this study, the surface characteristics of polyester and polyamide fabrics were changed by plasma polymerization technique utilizing acrylic acid as precursor. This monomer was used to produce hydrophilic materials with extended absorbency. The hydrophilicity, total wrinkle recovery angle (WRA°) and breaking strength of the fabrics were determined prior and after plasma polymerization treatment. The modification of surfaces was carried out at low pressure (<100 Pa) and low temperature (<50°C) plasma conditions. The effects of exposure time and discharge power parameters were optimized by comparing properties of the fabrics before and after plasma polymerization treatments. It was shown that two sides of polyester fabric samples were treated equally and homogeneously in plasma reactor. For polyester fabrics, the minimum wetting time, 0.5 s, was observed at two plasma processing parameters of 10 W–45 min and 10 W–20 min, where untreated fabric has a wetting time of 6 s. For polyester fabrics, the maximum value was obtained at 60 W–5 min with the wrinkle recovery angle of 306° where the untreated fabric has 290°. The optimum plasma conditions for polyamide fabrics were determined as 30 W–45 min where 2 s wetting time was observed. Wrinkle recovery angle of untreated polyamide fabric was 264°. In this study, after plasma polymerization of acrylic acid, wrinkle recovery angle values were increased by 13%. No significant change was observed in breaking strength of both fabrics after plasma treatment. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2318–2322, 2007     

Studying smoldering to flaming transition in polyurethane furniture subassemblies: Effects of fabrics,flame retardants,and material type

The transition from smoldering to flaming was studied on fabric, batting, and foam assemblies via an electric spot ignition source of similar intensity to a cigarette. The materials studied included four different fabrics (cotton, polyester, cotton/polyester blend, flame retardant cotton/polyester blend), two types of batting (cotton, polyester), and three types of polyurethane foam (nonflame retardant, flame retardant by FMVSS 302 testing, flame retardant by BS5852 testing). The results from testing found that materials highly prone to smoldering could propagate smoldering into foams and lead to ignition, whereas materials that tended to melt back from the ignition source did not. Flame retardant fabrics or foam can and do prevent the transition from smoldering to flaming provided sufficient levels of flame retardants are incorporated in the upholstery fabric or foam. The transition from smoldering to flaming of cotton fabric/nonflame retardant foam assembly was also studied using temperature measurements and evolved gas analysis. It was determined that the transition takes place when the oxygen consumption by accelerating smoldering front exceeds the oxygen supply. At this point, the solid fuel gasification becomes driven by thermal decomposition rather than by surface oxidation which leads to high enough concentrations of fuel for flaming combustion to occur.     

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.     

Thermal stability and flame retardancy of polyester,cotton, and relative blend textile fabrics subjected to sol–gel treatments

Polyester (PET), cotton (COT), and two relative blend textile fabrics were treated by sol–gel processes. Tetraethoxysilane (TEOS) was used as inorganic precursor of silica phases; furthermore, different TEOS/H₂O ratios were examined to explore the effect of the presence of SiO₂ on the thermal and fire stability of the textile fabrics investigated. The distribution and dispersion of SiO₂ were observed by means of scanning electronic microscopy (SEM). SEM magnifications showed the formation of a continuous silica film located in the neighboring fibers; furthermore, in the case of PET, such a film incorporated silica particles with an average diameter ranging between 0.2 and 6 μm. The thermal and thermooxidative stabilities of the treated samples were investigated by thermogravimetric analysis: after the sol–gel treatment, the degradation mechanism was modified both in nitrogen and in air, and the improvement in the thermal stability was attributed to the presence of silica, which played a protective role in the degradation of the textile fabrics. Finally, we investigated the combustion behavior of the textile fabrics by cone calorimetry, measuring the time to ignition, the heat release rate, and the relative peak. The former was found to depend on the type of fabric; the latter generally evidenced a remarkable decrease for all of the treated samples, up to 35% compared to the neat counterparts. This indicated that the sol–gel treatments improved the flame retardancy of the PET/COT fabrics. This conclusion was also confirmed by limiting oxygen index tests, which evidenced burning kinetics changes in the presence of the silica coating. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

聚氨酯改性聚醚嵌段聚硅氧烷的合成、表征及应用

用Si—H封端的聚甲基氢硅氧烷与烯丙基聚醚的硅氢化加成反应,合成了羟基封端的聚醚-b(嵌段)-聚硅氧烷(PESO),再将其与2,4-甲苯二异氰酸酯(TDI)反应,制得了聚氨酯改性聚醚-b-聚硅氧烷(TESO)。用IR、1HNMR、SEM等对TESO进行了结构表征、成膜性观察及应用效果考察。结果表明,TESO能与阴阳离子树脂、助剂配伍使用;在100%棉、聚酯/黏胶(T65/C35)纤维表面,TESO可形成一层相对光滑的亲水性硅膜。经TESO整理后的棉织物,其径(w)、纬(f)向弯曲刚度分别从整理前的146.5(w)、318.8(f)mN下降为106(w)和189(f)mN,折皱回复角(w+f)则从129°增大至220.8°,而织物的静态吸水时间却只有2.68 s。可见经TESO处理后的织物柔软性增加、弹性增强,吸湿性良好。     

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.     

Thermal analyses of flame-retardant twills containing cotton,polyester and wool

Medium weight twill fabrics constructed from cotton and cotton blended with polyester and/or wool were analyzed under nitrogen by three thermoanalytical techniques. Fabrics were tested both before and after treatment with [tetrakis(hydroxymethyl)phosphonium] sulfate (THPS), urea, and trimethylolmelamine. The presence of all fibers was distinguishable in differential scanning calorimetric analysis (DSC) of untreated fabrics; the relative positions of the endothermic, decomposition peak temperatures were only slightly changed. After flame-retardant (FR) treatment, the blended cotton and wool fibers were altered. Both fibers decomposed as exotherms during DSC analysis. These data supported earlier microscopical, X-ray evidence that wool fibers were actually reacting with the FR treatment. The two DSC peaks for polyester polymer melting and decomposing remained unaffected by either blending with other fibers or the presence of the FR finish on the fabric. There was excellent agreement between DSC peak temperatures and the temperature of maximum rate of weight loss obtained from thermogravimetric analysis (TGA). Blending cotton with either of these fibers increased the residue measured after TGA. The increased residue correlated with increased flame resistance as measured by the 45° angle, edge-ignition burning rate test.     

Chemical silver plating on polyester/cotton blended fabric

Chemical plating is a metallizing process that can impart unique properties to textile fabrics. It has great potential for use in textile production, especially in the functional and decorative aspects. The present study examined the feasibility of applying chemical silver plating to a polyester/cotton blended fabric (T/C fabric) as well as investigating the properties of the silver‐plated T/C fabric. It was found that chemical silver plating helped to produce T/C fabric with a novel appearance and to improve its performance. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4383–4387, 2006     

Textile heat release properties measured by microscale combustion calorimetry: experimental repeatability

In this research, we evaluated the repeatability of microscale combustion calorimetry (MCC) measurement of heat release properties for different textile fabrics including polypropylene, cotton, polyester, Kevlar, acrylic, nylon, silk, and the cotton treated with an organophosphorus flame retardant. The repeatability investigation was mostly based on the measurement of peak heat release rate (PHRR) and heat release capacity (HRC), the two most important heat release parameters measured by MCC. We found that PHRR and HRC of most textile fibers had coefficient of variance (CV) lower than and in the vicinity of 3.0. The CVs were influenced by both the standard deviation (SD) of measurements and by the values of these measurements. The use of an aerobic pyrolysis environment (80/20 nitrogen/oxygen) for MCC experiments did not affect the repeatability of measurement. We also evaluated the shift of the oxygen analyzer as a result of long‐term usage, and found that PHRR and HRC of cotton decreased between?4.0 and?3.9, respectively, after an 11‐month period, indicating that the shift of the oxygen analyzer is limited. Experimental factors influencing the MCC repeatability were also discussed. Copyright © 2011 John Wiley & Sons, Ltd.     

多层阻燃织物整体热防护性能初探

研究了消防服用多层阻燃织物复合系统的整体热防护性及外层织物的阻燃性。将阻燃织物国产间位芳纶、杜邦NomexⅢ和芳纶3A面料与国产间位芳纶毡和阻燃棉布组合,模拟构成消防服的多层织物结构,通过垂直燃烧实验测试分析了阻燃外层织物的阻燃性能,通过热辐射和热对流综合热防护性能(TPP)实验测试分析了多层复合织物的整体热防护性能。实验结果表明:整体热防护性能最好的是国产间位芳纶织物、面密度200 g/m2的芳纶毡和阻燃棉布的组合,但最适宜用于消防服的是NomexⅢ织物、面密度200 g/m2的芳纶毡和阻燃棉布。     

双层涤纶汽车座套面料的阻燃性能研究

选用不同比例的阻燃涤纶和普通涤纶长丝,设计织造了8种双层小提花织物,同时对织物进行了阻燃性能测试。结果表明:1#织物为最优织物,其采用接结双层组织,表里层为质量比1∶1的阻燃涤纶和普通涤纶,织物中使用的阻燃涤纶比例高,阻燃涤纶覆盖率系数大,织物的烫穿时间长,阻燃效果好。与纯阻燃涤纶织物相比,1#织物不仅达到了相同的阻燃效果,还减少了阻燃涤纶的使用量,节约了成本。设计织造的8种织物的阻燃性能均达到汽车用纺织品的阻燃要求,可以供企业在大生产中应用。