Developments in flame-retarding polyester/cotton blends

The burning behaviour of polyester/cotton blended fabrics is discussed and possible flame-retardant strategies outlined. Particular attention is paid to the effectiveness of phosphorous- and nitrogen-containing and antimony(III) oxide/halogen flame-retardant systems. Recent developments within the UK are discussed which suggest that phosphonium salt condensate finishes are effective on cotton-rich blends and that antimony-halogen systems may be used on all polyester/cotton blend compositions. Both types of flame retardant have acceptable durability to laundering.     

Preparation and performance evaluation of phosphorus-nitrogen synergism flame-retardant water-borne coatings for cotton and polyester fabrics

Three phosphorus-nitrogen content effective synergist flame-retardant water-borne coatings have been synthesized, and their structures were characterized by infrared spectroscopy. Cotton and polyester fabrics have been treated by coatings to improve their flame retardancy. The thermal performances and flame retardant properties of treated samples were investigated by thermogravimetric analysis (TGA), horizontal flame test, vertical burning test, limiting oxygen index (LOI), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS), respectively. The combustion performances of cotton and polyester fabrics have proven to be strongly affected by flame-retardant coatings and HFD-coating performed the best. As a result, the LOI value of treated cotton increased to 22.5, and the UL-94 value of treated polyester achieved V-0. In addition, the antistatic behavior, hydrostatic pressure, tearing strength and wrinkle recovery angle of samples were studied carefully, and the results showed that all of these performances were improved.     

Metal complexes of natural and synthetic fabrics grafted with vinyl monomers by gamma irradiation

Graft copolymers of natural and synthetic fabrics with acrylic acid (AAc) prepared by gamma irradiation were transformed into metal complexes of the divalent metal ions of cobalt, nickel, and copper. The factors that affect the grafting process without affecting the physical properties of fabrics and homogeneous grafting were studied. These factors involved inhibitor (FeCl₂) concentration, solvent composition, AAc concentration, and irradiation dose. The results showed that the appropriate irradiation dose in all cases was 20 kGy, whereas the inhibitor concentration was 0.1 wt% in the case of cotton and 0.2 wt% in the case of cotton/polyester blend and polyester fabrics. The suitable solvent composition was H₂O (90%)/MeOH(10%) in the case of cotton and H₂O (90%)/MeOH(10%) in the cotton/polyester blend and polyester fabrics. On the other hand, the suitable AAc concentration was 30% in the case of cotton and 50% in the cotton/polyester blend and polyester fabrics. The homogenous grafting and subsequent distribution of metal complexation was illustrated by a method based on the measurement of color parameters. Moreover, the effect of radiation grafting and metal complexation on the water absorption and mechanical properties of fabrics was investigated. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers     

Electrostatic self‐assembly dyeing of cotton fabrics

A new approach to the dyeing of cotton fabrics using an electrostatic self‐assembly method was evaluated. Cotton fabrics were pretreated with 2,3‐epoxypropyltrimethylammonuium chloride and cationic charges were produced on the fabric surfaces. For the dyeing of cotton fabric, reactive and acid dyes were used. Oppositely charged anionic reactive/acid dyes and cationic poly(diallyldimethylammonium chloride) were alternately deposited on the surface of cationised cotton fabrics. Ten multilayer films of dye/poly(diallyldimethylammonium chloride) were deposited on the cotton fabric surfaces using a padder. The build‐up of the multilayer films and the level of colour strength (K/S) achieved are discussed. Samples of cotton fabrics were also dyed with the same dyes, but using the exhaust method, and both types of dyed samples were compared. The washing, rubbing and light fastness properties were evaluated for the dyed fabrics.     

Flammability characteristics of cotton and polyester fibers

This study was undertaken to measure quantitatively the flammability characteristics of cotton and polyester fibers. The smoke density generated during the burning of these fabrics was also studied at various temperature conditions. A mathematical relationship was established between the results obtained in an oxygen-depleted atmosphere chamber and those obtained in a chamber in which there was constant replenishing of an oxygen and nitrogen atmosphere. Three commercially available flame-retardant treatments were utilized in this study. The effect of temperature as well as the influence of fabric weight on the flammability behavior and the smoke density of these fabrics were investigated. A novel instrument built according to ASTM standards was employed throughout this study; it was found to be versatile, convenient, and highly reproducible in the generation of the data. It was found that polyester fabrics generate far more smoke than cotton fabrics without the phenomenon of afterglow. It was found also that as the temperature increases, the smoke density of cotton fabrics increases as well, but in the case of polyester fabrics the opposite relationship was obtained.     

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.     

Surface treatment of cotton fabrics with chitosan

Antibacterial activities of cotton and polyester/cotton fabrics treated with chitosan or chitosan/DMDHEU have been investigated. The washing durability properties of the aforementioned fabrics were also studied. Another group of fabric samples produced from mature and immature cotton fibres were dyed with reactive dyes and the colour yields and colour differences of the dyed fabrics assessed. The surfaces of the treated and untreated cotton fabrics were observed by scanning electron microscopy to compare the morphology.     

Reusing textile waste as reinforcements in composites

Polyester (PET) has wide applications in textile industries as textile fiber and its share continues to grow. Substantial quantities of cotton/polyester blend fabrics are disposed every year due to technical challenges, which pose a big environmental and waste‐dumping problem. The aim of this study is to evaluate the potential of discarded cotton/PET fabrics as raw materials for composites. If their inherent reinforcement properties can be used in composites, an ecological footprint issue can be solved. In this study, we investigate three concepts for reuse of cotton/PET fabrics for composites: compression molding above the T_m of PETs, use of a matrix derived from renewable soybean oil, use of thermoplastic copolyester/polyester bi‐component fibers as matrix. All three concepts have been explored to make them available for wider applications. The effects of processing parameters such as compression temperature, time and pressure are considered in all three cases. The third concept gives the most appealing properties, which combine good tensile properties with toughness; more than four times better tensile strength than the first concept; and 2.2 times better than the second concept. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40687.     

Making fabrics water-repellent with fluorine-containing silane in supercritical carbon dioxide medium

It was shown that fluorine-containing silane, 2,2,3,3,4,4,5,5,5,6,6,7,7-tridecafluoro-N-[3-(triethoxysilyl)propyl]-heptane amide, is an effective water-repellent for different fabrics. Its application from solution in supercritical carbon dioxide followed by heat treatment gives the surfaces of fabrics stable water-repellent properties. The use of SC-CO₂ as a universal medium for treating fabrics allows eliminating the use of organic solvents, which significantly reduces the ecological load on the environment, simplifies the manufacturing process, and makes it safer. Translated from Khimicheskie Volokna, No. 1, pp. 39-44, January-February, 2009.     

Effect of fiber substrates on appearance and removal of aged oily soils

Aging of oily soils produces difficult-to-remove yellow stains on fabrics. This study examines the effect of different textile substrates on yellowing and removal of aged oily soils. Model oily, squalene and artificial sebum, were aged at 40°C on cotton, nylon, and polyester fabrics for 8 wk. Radiotracer and spectrophotometric analyses were used to quantify volatilization and color change of soiled fabrics upon aging as well as soil and color removal after laundering. Differences in volatility of oils from three substrates were insignificant, although cotton and nylon fabrics produced significantly more yellowness than polyester fabrics. Aging of oily soil enhanced detergency from all three fabrics. The largest increase in removal upon aging was found with cotton. Difference in removal from the three substrates became very small after aging. The effect of substrate was pronounced on yellowing due to aging with cotton and nylon having higher yellowness indices. Cotton visually appeared to be cleaner than indicated by the actual amount of residual oil present after washing, whereas nylon had less residual oil present even though it visually appeared more yellow than cotton. For polyester, the amount of residual oil correlated well with appearance after washing. We conclude that discoloration mechanisms differ among cotton, polyester, and nylon substrates. For polyester, discoloration is solely discoloration of oily soil that is physically bound in the fibrous structure, whereas for cotton, discoloration is a result of discoloration of oil as well as additional yellowing caused by retention of chromophores chemically bound to the cotton substrate. In the case of nylon, yellowing of nylon itself is an additional factor contributing to yellowness even though, most of the oil is removed upon washing. These results illustrate the importance of the method of detergency evaluation. Measuring color change in yellowness or reflectance is not the same as oil removal based on a quantitative measurement of soil mass. Thus, it may be necessary to measure both color and quantity of residual soil.     

阻燃涤纶汽车座套面料的研究和开发

采用阻燃涤纶和普通涤纶作为原料,研究了阻燃涤纶和普通涤纶交织混合时,混用的比例对织物阻燃性能的影响;并根据汽车座套面料的要求设计了不同层数的织物,研究其对使用性能和舒适性能的影响。从织物的阻燃性和使用性能综合分析,得出普通涤纶与阻燃涤纶比例为1∶2的双层织物为最佳方案。     

Flame-retardant Finishing of Textiles

The need for flame-retardant finishing of textiles is examined in the context of the hazards of textile flammability, associated legislation and procedures for assessing textile burning behaviour. The functions of flame-retardant finishes and durable finishes developed specifically for cellulose, wool and man-made fibres are described in depth. Multipurpose finishes for both cellulose and wool textiles in which flame retardancy is only one property conferred on the textile are examined. Fibre blends present a particular problem and special attention is paid to discussing those finishes applied to polyester/cotton blended fabrics. The laundering behaviour and consequent finish durability are reviewed. In addition, the effects that applying flame-retardant finishes have on textile properties and performance are considered. Recent developments in methods used to apply flame-retardant finishes are outlined.     

Synthesis of a graft-functionalized flame retardant based on DOPO and its application on the surface of terylene/cotton fabrics

Terylene/cotton (TC) fabrics are widely used in the textile industry because of their superior softness and durability. In addition, its high combustibility leads to a great safety hazard, and the droplet phenomenon during combustion is particularly serious. 9-oxa-10-phospha-9,10-dihydrophenanthrene 10-oxide (DOPO) and its derivatives are frequently used as eco-friendly flame retardants in large quantities in substrates. It would be difficult to apply to the surface of the fabric, and the addition of large amounts would lead to a decrease in the mechanical properties. Therefore, it is necessary to design a strategy for graft-functionalized flame retardants that can be applied to surfaces. Here, this study reported a washing-fastness flame-retardant coating (DOPO-p) synthesized from DOPO and p-hydroxybenzaldehyde (p-HBA), coatings with a low weight growth and high flame-retardant efficiency are prepared by the strategy of dissolving with organic solvents. Water and dry-cleaning tests showed excellent washing fastness of TC fabrics. In the limiting oxygen index (LOI) test, the finished fabric achieved a LOI value of 22.9%. In the cone calorimetry test, the peak of heat release rate of the finished fabric is decreased by 27% and CO₂ release is reduced by 29% when the coating weight growth was only 3.3 wt%.     

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.     

涤棉织物化学回收工艺研究

以废旧涤棉织物为原料,乙二醇(EG)为醇解剂,通过改变醇解时间、醇解温度、EG/废旧涤棉织物中聚对苯二甲酸乙二醇酯(PET)质量比(mEG/mPET)、催化剂种类及用量等研究了蓬松态下废旧涤棉织物的醇解工艺,以及醇解过程对涤棉织物中棉纤维性能的影响。结果表明:随着醇解时间、醇解温度的提高,mEG/mPET的增大,涤棉织物的醇解程度增大,各参数达到一定程度后醇解程度基本不变;最佳醇解工艺为涤棉织物中mEG/mPET为2/1,催化剂用量为涤棉织物中PET质量的0.30%,醇解温度196℃,醇解时间1 h;在乙酸锌、碳酸钠、乙酸钾、氯化镁4种催化剂中,碳酸钠综合催化效果最佳;经醇解过程后涤棉织物中棉纤维表面变得粗糙,力学性能有较大下降。     

Effect of in situ deposition of calcium carbonate in cotton fiber on its mechanical properties

In this study, in order to improve mechanical properties of cotton fabrics, nano-micro sized calcium carbonate (CaCO₃) was deposited in situ on cotton fabrics. The mechanical properties, surface morphology, crystalline index, infrared spectrum, thermal property, and wettability of the deposited fabrics were measured and discussed. The results showed that the breaking strength of cotton fabric increased by about 10% after in situ deposition of nano-micro calcium carbonate. After ultrasonic washing, the strength of cotton fabric deposited CaCO₃ was still increased by about 10%. The crystallinity of the cotton fabric deposited with calcium carbonate increased from 76% to 84%. The hydrogen bond between cellulose molecules and calcium carbonate was confirmed by infrared spectroscopy. The hydrophilicity and thermal properties of cotton fabric were not significantly influenced by calcium carbonate deposition. This provides a new idea for improving the mechanical properties of cotton fabric.     

防紫外超疏水织物的制备及耐久性评价

采用全纳米颗粒自组装的方法,在棉、锦纶和涤纶织物上制备了TiO_2/SiO_2薄膜,再经十六烷基三甲基硅烷修饰,得到了兼具抗紫外及超疏水功能的多种织物。自组装过程中分别以SiO_2和Ti_2溶胶为原料,逐层于聚电解质表面处理的织物上组装了TiO_2/SiO_2多层薄膜。经扫描电子显微镜(SEM)测试表明,膜层均匀沉积在织物纤维表面。接触角测试表明,疏水处理后表面水的接触角可达172°。紫外可见分光光度计测试表明,经TiO_2/SiO_2修饰后,织物在紫外光区的吸光度成倍提高。用耐老化、耐摩擦、耐水流喷射等耐久性试验评价了织物在使用过程中可能遇到的各种破坏,证明自组装再经疏水剂处理的织物具有良好的耐久性。     

负载织物对纳米TiO2光催化剂净化氨气性能的影响

制备了纳米光催化剂悬浮液,借助后整理工艺对3种织物进行负载加工,并利用X射线衍射仪(XRD)和扫描电镜(SEM)等对其进行了表征. 通过自行设计的小型环境舱和光催化反应器重点考察了棉机织物、涤纶机织物和涤/棉混纺机织物对纳米光催化剂净化氨气性能的影响,并比较了在不同负载织物表面上纳米光催化剂的活性. 结果表明,负载纳米光催化剂的棉织物的氨气净化性能高于负载纳米光催化剂的涤纶织物和涤/棉混纺织物的氨气净化性能. 在负载Ag-TiO2光催化剂的条件下,负载涤纶织物和涤/棉混纺织物对氨气的净化性能有所加强.     

Polyimide-coated fabrics with multifunctional properties: Flame retardant,UV protective,and water proof

Multifunctional technical textiles are of great interest both by industry and academia and these products are considered as high value-added products that contribute to the economies of countries. In this study, polyamic acid (PAA) was synthesized through polycondensation of pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (ODA) in dimethyl acetamide (DMAc) at low temperature. Then, PAA was coated onto woven cotton and polyester fabric by padding technique. Finally, polyimide (PI)-coated multifunctional cotton and polyester fabrics were obtained by an easy coating technique and low-temperature imidization. Thus, low cost, easily accessible and widely used cotton and polyester fabrics were converted to high-performance textile products, which are flame retardant, UV protective, acid resistant, and waterproof. The chemical, thermal, morphological, optical, mechanical, wettability, chemical resistance, and flame retardancy properties of developed fabrics were investigated. Optical results showed that both PI-coated cotton and polyester fabrics are UV-A protective compared to noncoated fabrics. Moreover, PI-coated samples have high contact angles which are 111.43° and 113.40° for PI-coated cotton (PI-c-C) and PI-coated polyester (PI-c-PET), respectively. Young's modulus of PI-c-PET fabrics increased four times more than noncoated polyester fabric. PI coating changed the burning behavior of both cotton and polyester fabrics in a positive way. All the test results showed that these developed multifunctional textile products might find an application in different industrial areas such as automotive, aerospace, protective clothing, and so on due to easy and inexpensive production techniques and also superior properties. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47616.     

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.