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Many flame retardants (FRs) are brominated, and many of them are considered toxic, persistent and/or bio accumulative. A switch to non-halogenated alternatives for textile finishing is considered beneficial, but there is little knowledge about their environmental impact, their health risks during the production process and those in their final use. A conventional and an alternative FR (based on dialkyl phosphono carboxylic acid amine and ammonium sulfamate; urea and organophosphonate PO(OH)2-R-PO(OH)2, respectively) were applied to cotton fabrics that could be in touch with the skin in their final use. Burning and thermal behaviors and dermal toxicity when exposed to skin rubbing are evaluated. Fabrics treated show that both FR products act as FRs. The increase in the thermal stability of the tissue that causes an increase in the decomposition temperature is a relevant effect associated with the application of the conventional FR in the tissue, while the most important effect of the alternative FR lies in the increase of the residue at 600°C, associated with the generation of fewer volatiles, which has an impact on the intensity of combustion. The study of the dermal toxic potential of FR-treated cotton bed sheets showed that the two tested products do not penetrate into the skin when applied under the conditions used and were safe when in contact with the skin. Moreover, the alternative FR seems to be safer when in contact with the skin considering also its higher concentration in the textile. [ABSTRACT FROM AUTHOR]

Recently, a significant interest in eco-friendly textile products and processes has been noted among consumers and producers. In this respect, nanobubble technology is emerging as a green alternative. In this study, water-repellent cotton fabrics were produced with exhaustion and nanobubble technology (e-flow method) using a short-chain fluoropolymer. The currently most developed substituents are based on molecules with short fluorine carbon chains. The wettability, mechanical properties, air permeability and treatment durability were evaluated. The untreated and treated cotton fabrics were analyzed with ATR-FTIR (Fourier transform infrared attenuated total reflectance) and SEM (scanning electron microscopy) to reveal chemical and morphological modifications. The obtained results show that cotton samples treated with short-chain fluoropolymers, nontoxic and eco-friendly finishing chemicals, and nanobubble technology have good water repellence and good washing durability. Due to their size and structure, nanobubbles possess distinct properties that make them particularly effective at improving water quality, enhancing water treatment processes, and improving productivity in industrial applications. Nanobubbles have a strong negative surface charge that keeps them stable in liquid, prevents them from coalescing, and enables them to physically separate small particles and droplets from water, such as emulsified fats, oils, and grease. [ABSTRACT FROM AUTHOR]

The influence of the alkaline delignification of hemp on its moisture uptake has been studied under the project "Preparation and functionalization of hemp for textile substrates" focussed on the reduction of cotton imports for the manufacturing of clothing, household textiles and medical devices. The project looks for the partial replacement of cotton by hemp on the production of natural cellulosic textiles. Hemp fibres are alkaline delignified at different times to evaluate its effect on their moisture uptake behaviour to evaluate the ability of replacing cotton in the next-to-skin goods manufacturing. The paper gives three easy tools to analyse the moisture uptake behaviour by determining the sorption ratio, the hysteresis and the parameters of the isotherms fitted using three different models (GAB, Hailwood-Horrobin and Dent) to the absorption desorption isotherms. The samples of the original and delignified hemp have been subjected to moisture absorption/desorption trials from 5% to 95% RH at 25 °C. Sorption ratio and hysteresis reveal the greater influence of lignin on moisture uptake at low relative humidities, while at high, was cellulose which plays the most important role. The models fitted to the isotherms show that delignification decreases the size of the monolayer that, in desorption results always greater than in absorption. The energy constants of the monolayer for delignified fibres in absorption were higher than those for the original fibres, while the opposite occurred in desorption. Lignin caused great differences between absorption and desorption. The energy constants of the multilayer show a greater range of variation in delignified samples than in the original one, and results in absorption were higher than those in desorption. Delignification time of 3 h reached the highest cellulose content which best approached to the cellulose content of cotton causing that the moisture uptake behaviour drew near to it, especially at higher relative humidity. [ABSTRACT FROM AUTHOR]

Raw hemp (Cannabis sativa L.) was subjected to alkaline delignification with the application of NaOH ranging from [0.125M] to [1M] for times from 5 to 480 min. Lignin contents of the original and delignified samples were determined. The samples were subjected to thermogravimetric analysis (TGA) under a N2 atmosphere with temperatures ramped from 25 to 600 °C at 10 °C min-1. Lignosulfonates samples of low, medium and high molecular weight were subjected to the same TGA and showed that lignin decomposed over the entire temperature range. The contributions of lignin to the mass loss during thermal decomposition of hemp and kinetics of lignin content and the most relevant TGA results were determined. Regression models estimating the lignin content of the fibers based on TGA results were formulated. These models allow for the prediction of mean lignin content within ± 0.1% (based on dry weight of pulp) in the central range of the experimental field. [ABSTRACT FROM AUTHOR]

Raw hemp fibers are alkaline delignified to evaluate the effect of lignin on the moisture uptake behavior of hemp. Samples are subjected to moisture absorption/desorption isotherms from 5% to 95% relative humidity at three different temperatures (15, 25, and 35°C). The sorption ratio between delignified and untreated hemp is lowered by 25%. Hysteresis makes evident the greater influence of lignin on moisture binding at low relative humidity while at high relative humidity, cellulose plays the most important role. The GAB, Hailwood‐Horrobin and Dent models are fitted to absorption/desorption isotherms. Delignification and temperature decrease the size of the monolayer. The energy constants of the monolayer differ according to the model used. Lignin causes great differences between absorption and desorption. The greater the temperature is, the lower the monolayer energy constant. The energy constants of the multilayer are identical for the three models, showing a greater range of variation in delignified samples than in the untreated samples. Based on primary and secondary energy constants, bonding enthalpies are determined. Estimations in desorption show higher correlation coefficients with the energy constants, which enables to conclude that measures in desorption better explain the effect of delignification on the water uptake behavior of hemp. [ABSTRACT FROM AUTHOR]

Hemp (Cannabis sativa L.) is a plant of which, its ease of cultivation, structure and properties, provide it great potential for industrial applications; nevertheless, the unfavorable content of lignin complicates its processing, especially in the textile area. Thus, an appropriate knowledge of the delignification process would lead to treating hemp fibers as cotton fibers. In this work, hemp has been treated with an alkaline liquor [NaOH 1 M] at 110 °C during different times and afterwards, the substrates were chemically characterized in order to determine their lignin content and also analyzed by thermogravimetry (TGA). Through the correlation analysis, the relationship between lignin content, onset temperature of cellulose decomposition and loss of mass at the different decomposition steps were established. A hyperbolic kinetic model to explain the influence of alkaline treatment time on lignin content and also on the loss of mass at the four steps of decomposition of the samples by TGA up to 600 °C has been developed. Although it has been found that the degradation of lignin occurred across the entire temperature range, results have shown that the influence of treatment time has become clearly relevant on lignin content, Step2 (180.5 °C-273.5 °C) where a fraction of 10 to 16% of lignin was degraded, and Step3 273.5 °C-396.5 °C) where cellulose was mainly decomposed and 20% of lignin was also degraded. [ABSTRACT FROM AUTHOR]

In textile printing, hydrotropic components are usually added to print paste formulations promoting the hydration of textile fabrics by disrupting the hydrogen bonding network between water molecules. For this purpose, urea is commonly used but nevertheless, its presence causes water eutrophication and their reduction or replacement by more environmentally-friendly products is required. In the present work, we have studied an alternative hydrotropic product (polyethylene glycol, PEG) to replace urea. A factorial design of experiments has been carried out to identify the factors that optimize several variables of interest such as viscosity of the printing paste and fabric colour strength. The results showed that a reduction of 70 wt% of urea was achieved by using PEG 400, while preserving the performance of printing formulation. The viscosity of these eco-friendly printing paste formulations was similar to that of the original urea-based formulations and, more interestingly, fabrics showed similar colour strength and fastness to those of fabrics printed by the conventional method. [ABSTRACT FROM AUTHOR]

Objective: The main aim of this study is to characterize the external lipids of different ethnic hairs and to study the contribution of the exogenous lipids on their physicochemical properties. Methods: On the extraction procedure, sebaceous lipids from the exterior of the fiber are removed. The influence of those free lipids on the hair properties, such as contact angle, mechanical characteristics, and sorption of water, will be evaluated to determine permeation characteristics of the keratin fibers. Relationship with lipid order was also determined by infrared spectroscopy (IR). Results: Lipid extraction indicates the greatest amount of total lipids for African hair. Caucasian lipid extracts present the higher melting point and phase transition temperatures. This could be related to higher hydration and lower diffusion coefficient of the Caucasian fibers. A decrease in moisture was found in the lipid‐extracted fibers. This diminution of the maximum water regain in all cases could be due to a higher water desorption. IR results indicate that Caucasian and moreover African native fibers present the most quantity of lipids, and the similar frequency of all fibers indicates a lamellar/orthorhombic order arrangement. Conclusion: The hexane/tert‐butanol extraction was demonstrated to modify not only cuticular but also cortex lipids. Exogenous lipid depletion in all fibers indicates a less water content and higher water desorption. However, lipid depleted Caucasian fibers presents an increase in the lipid order which could be related to the different saturation of the lipid extract and its improvement in breaking tenacity. [ABSTRACT FROM AUTHOR]

A preformulation study of an oral lyophilisate with cetirizine dihydrochloride (CTZ) as active ingredient, mannitol and PVP K30 as bulking agents is presented. CTZ shown a humidity content of 0.150% and a spontaneous hygroscopicity of 0.200% (both determined by SeDeM diagram), demonstrating an adequate stability behavior in solid form. A design of experiments (DoE) performed with both mannitol and PVP K30, followed by a simple factorial design (32) has determined the optimum combination of excipients and CTZ, and showed that a higher proportion of PVP K30 was able to prevent metastable forms generated by mannitol. [ABSTRACT FROM AUTHOR]

Context: Nowadays, the entire manufacturing process is based on the current GMPs, which emphasize the reproducibility of the process, and companies have a lot of recorded data about their processes. Objective: The establishment of the design space (DS) from retrospective data for a wet compression process. Materials and methods: A design of experiments (DoE) with historical data from 4 years of industrial production has been carried out using the experimental factors as the results of the previous risk analysis and eight key parameters (quality specifications) that encompassed process and quality control data. Results: Software Statgraphics 5.0 was applied, and data were processed to obtain eight DS as well as their safe and working ranges. Discussion and conclusion: Experience shows that it is possible to determine DS retrospectively, being the greatest difficulty in handling and processing of high amounts of data; however, the practicality of this study is very interesting as it let have the DS with minimal investment in experiments since actual production batch data are processed statistically. [ABSTRACT FROM AUTHOR]

Polyester fibers (PET) are greatly used in textiles but depend on fossil fuel resources. Poly-(lactic acid) (PLA) is an aliphatic polyester that can be derived from 100% renewable resources. The load–extension plot of a polylactide fiber seems to be especially compatible with that of wool. Consequently polyester/wool 55/45 and polylactide/wool 55/45 yarns were spun using the Sirospun process and plain and twill woven fabrics were industrially produced. Washed and heat set fabrics were subjected to a conventional process of dyeing and decatizing. Fabrics were gradually worn by abrasion using a Martindale wear and abrasion tester.Using the bursting strength test, the viscoelastic behavior of the fabrics when multidirectional extended was simulated and modeled using a modified non-linear Maxwell model. The three steps of fiber decrimping and orientation, fiber stretching and maximum yield and breaking were analyzed. PET/wool fabrics show a more linear behavior than PLA/wool ones and the influence of weave, finishing and wearing on the viscoelastic behavior of PLA/wool fabrics were highly relevant when compared with that on PET/wool ones. It seems that when blended with PET, wool develops its felting effect during finishing and wearing, while when blended with PLA, the felting effect of wool is hardly developed due to the lower resistance of PLA to hydrolysis and its lower thermal stability. PLA fiber properties need to be improved probably through the development of new L-D lactide (PLDLA) copolymers of different ratios between components and molecular weights to reach the optimal desirable properties for the fiber. [ABSTRACT FROM PUBLISHER]

Effects of fabric extensibility and stitch density on seam slippage and strength behavior of elastic woven fabrics have been studied. Six fabric samples with different values of elasticity have been woven by changing the number of elastic core-spun cotton yams and normal ring cotton yarns in the weft direction and then finished for sewing process. The samples are sewn with three stitch density levels (4, 5 and 6 stitches/cm) in warp direction and one stitch density level (5 stitches/cm) in weft direction. Fabric tensile properties, seam slippage load and seam strength have been measured and analyzed both in warp and weft directions. The results show that seam slippage and strength properties can be well explained in terms of fabric tensile properties. In general, increase in fabric extensibility leads to decrease in seam slippage load and seam strength in weft direction. In warp direction, seam slippage load also decreases with increase in fabric weft extensibility, whereas seam strength remains invariant. The results also reveal that the increase in stitch density results in a higher seam slippage load and strength value. [ABSTRACT FROM AUTHOR]

Expandable graphite was applied to an upholstery polyester textile material as an eco-friendly flame-retardant alternative to halogenated compounds. Fabrics treated with the flame retardant were evaluated by flammability tests. Besides, thermal analysis was carried out by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). Moreover, a percutaneous absorption study was conducted to verify the safety in terms of dermal penetration of the flame-retardant treated upholstery fabric for human use. The upholstery fabric treated with expandable graphite successfully passed the flammability tests. Thermogravimetric analyses with TGA and DSC showed that the flame-retardant application slightly decreased the initial decomposition temperatures regardless of the atmosphere but increased the final residue at 600°C (35.7% in O2 and 44.5% in N2) compared to non-treated upholstered fabrics. Dermal permeation of expandable graphite applied on the polyester fabric showed no penetration after 24 h of fabric exposure time. This result demonstrated that graphite-treated polyester fabric is dermatologically and toxicologically safe for use in upholstery. Applied expandable graphite proved an efficient and safe flame-retardant alternative to conventional flame retardants for eco-friendly flame resistance applications in upholstery fabrics. [ABSTRACT FROM AUTHOR]

Polylactide fibers (PLA), textured by false twist at different temperatures (135, 150 and 165℃) and draw ratios (1.30, 1.35 and 1.40) were stabilized by the application of a continuous thermal treatment at 100℃ and 50 m/min. The effect of thermal stabilization on the microstructure was determined by physicochemical tests such as iodine sorption or differential solubility. Iodine sorption and differential solubility are closely related to the crystallinity of the samples. Stabilization enhances crystallinity and orientation with the result that differences between the samples are diminished. Color value differences, albeit reduced, in some cases exceed the accepted limits. Color absorption is mainly dependent on the orientation and accessibility of the amorphous phase. [ABSTRACT FROM PUBLISHER]

Polylactide fibers (PLA), false-twist textured at different temperatures (135, 150 and 165℃) and draw ratios (1.30, 1.35 and 1.40) were stabilized by a continuous setting treatment at 50 m/min and 100℃ using a specially designed chamber. The crystallinity and the orientation of the original textured filaments and those of the stabilized ones were measured. The effect of post setting on the dimensional stability, mechanical properties and thermomechanical behavior in accordance with the texturing conditions was studied. The relationships between crystallinity and the dimensional stability and between the orientation and both the relaxation shrinkage and the endset temperature of shrinkage were considered. [ABSTRACT FROM PUBLISHER]

The characterization of the microstructure of synthetic fibres is necessary to identify changes in properties produced by differences in the production variables. To this end, two physico-chemical tests (iodine sorption and differential solubility), which are easy and rapid to implement were employed to study the differences in the microstructure of polylactide false-twist textured multifilaments. The results enabled us to identify variations in microstructure induced by texturing conditions and were related to processing variables. These tests were compared with more expensive and complicated techniques to quantify crystallinity and orientation of filaments. Both tests enabled us to identify microstructure variations between substrates. [ABSTRACT FROM PUBLISHER]

Polylactide multifilament yarns were textured in order to be endowed with properties of natural staple fibre yarns for textile applications. Texturing promotes the formation of stable secondary links between the macromolecular chains. A polylactide 167/68 dtex multifilament yarn was textured under different conditions. Relaxation experiments at yield, strain softening, strain hardening and just before breaking were performed. The relaxation behaviour was studied by the application of the generalized Maxwell model. The initial stress induced when stretched, the final non-relaxed stress after relaxation and the stress relaxed at different times were determined. Variations in the relaxation behaviour were related to texturing conditions and stretching. [ABSTRACT FROM PUBLISHER]

Ceramides extracted from wool fibers have proved to be beneficial in pharmaceutical and cosmetic formulations in the treatment and care of skin and human hair. This work sought to obtain internal wool lipid extract enriched in ceramides at pilot plant level without causing significant damage to the wool fiber. To this end, two extraction methodologies were performed using two solvents — acetone and methanol. Analyses of wool extracts were performed by thin layer chromatography coupled to an automated ionization detector, and chemical and mechanical evaluations of extracted wool were carried out. Larger amounts of ceramides were obtained when wool fibers were extracted with methanol than with acetone with some modifications of the fiber properties. This lipid extract could be a by-product with a high added value for the wool industry. [ABSTRACT FROM AUTHOR]

Lipids from human hair consist mainly of cholesterol esters, free fatty acids, cholesterol, ceramides, and cholesterol sulfate. They are structured as lipid bilayers in the cell membrane complex (CMC) and make a large contribution to diffusion, cell cohesion, and mechanical strength. The loss of these lipids could impair the integrity of the hair, leading to deterioration in its tensile properties. Internal wool lipids (IWL) resemble those of the membranes of other keratinic tissues such as human hair or stratum corneum. The application of IWL structured as liposomes on pretreated hair samples has been demonstrated to restore the natural properties of the fibers. This study seeks to apply IWL liposomes to untreated hair fibers and to hair fibers subjected to chemical treatment. Differences in the lipidic composition of all chemically treated hairs were found with respect to the untreated ones. Lipid recovery of damaged hair due to the application of IWL liposomes was corroborated by lipid analysis of the hair. A high resistance to break of hair samples post-treated with IWL liposomes was observed. An increase in hydrogen bonds and electrostatic forces and an improvement in the cohesion between matrix and filaments were detected, probably because of some lipid recovery.

Toxic Oil Syndrome (TOS) was a massive food-born intoxication that occurred in Spain in 1981 and affected more than 20,000 people. TOS was attributed to the ingestion of rapeseed oil that had been adulterated with aniline, illegally refined, and delivered for human consumption. Two chemical species derived from aniline have been identified in oil batches: fatty acid anilides, qualified as biomarkers of the adulterated oil, and fatty acid esters of 3-(N-phenylamino)propane-1,2-diol (PAP), considered toxic oil biomarkers. These esters were generated by chemical processes during oil refining, specifically in the deodorization step, which involves treatment of the oil at high temperatures under vacuum to remove volatile contaminants. Since PAP derivatives are strongly associated with TOS, their formation and putative interconversion in a toxic oil model has been studied. The main results obtained are (i) only triglycerides and aniline are required to produce PAP esters, thus eliminating the possibility that unknown activators present in the deodorization tank were required for toxification of the oil; (ii) PAP and PAP mono- and diesters are chemically interrelated, as are anilides and PAP esters to an even higher degree. In addition to the reaction of aniline with triglycerides, anilides can be also formed via attack of PAP esters by aniline. However, the most important source of anilides during deodorization seems to be the thermal decomposition of PAP esters. Overall, these results suggest that the generation and outcome of PAP derivatives during deodorization is a complex scenario whereby PAP esters are not only generated from different reactions but decompose to produce anilides, among other compounds. In addition to providing a rapeseed oil model that reproduces the composition of case oils with respect to anilides and PAP derivatives, the results presented herein further support the hypothesis imputing PAP diesters or their metabolites for the intoxication episode.