The effect of radical scavengers on the control of β-scission of polypropylene (PP) during the free-radical grafting with maleic anhydride (MAH) in melt was investigated. The main interest was the evaluation of the effective concentration of radical scavengers Irganox 1010 (IRN1010) and Irgafos 168 (IRF168) for better control of grafting process. For this purpose, radical grafting of non-stabilized PP was performed in order to describe specifically the effect of proposed additives with no effect of additives in commercial PP grades. For this purpose, the influence of the initial concentration of IRN1010 ([IRN1010]0) on the reaction course was predicted with respect to the change of kinetic parameters, thermal and rheological properties of PP-g-MAH. Obtained results showed that the efficiency of IRN1010 and IRF168 is not proportional to their concentration above critical level as evidenced by rheological properties of PP-g-MAH. Above that point, both the grafting efficiency and grafting rate decrease and thus the determination of effective cIRN1010 is the key for approaching controlled radical grafting of PP.

The thermal decomposition mechanism of raw and treated bagasse fibers was modeled with three parallel independent first-order reactions. The kinetic parameters and pseudo components which best fit the experimental dynamic pyrolysis rate of bagasse was determined by means of the Matlab program using the least-square method. The calculated rate of thermal decomposition for each bagasse sample was consistent with experimental pyrolysis rate very well. A method was adopted to calculate the contents of cellulose, hemicelluloses, and lignin for bagasse fiber based on the dynamic pyrolysis model. The calculated contents of the untreated bagasse fiber agreed very well with some reported values from the literature. The effect of treatment conditions on the bagasse fiber compositions was also studied. From the three-dimensional plot for each of the three components, it could be observed that bagasse fibers treated under the intermediate alkaline condition could achieve the higher content of cellulose.

PurposeThe purpose of this paper is to investigate the effect of laundering on the drape, shear, and bending properties of bottom weight fabrics.Design/methodology/approachSix bottom‐weight 100 percent cotton fabrics were included. Collier's Drape Tester was utilized to obtain drape values. Bending and shear values were measured on the KES‐F Shear Tester and the Pure Bending Tester. Three laundering cycles (unlaundered, one and five home launderings) following AATCC methods were explored.FindingsLaundry cycle did not have a significant effect on fabric drape, shear or bending properties. However, drape values increased overall, while shear and bending modulus and hysteresis decreased, resulting in a more drapable, pliable fabric after five laundry cycles.Research limitations/implicationsFuture research examining a wider variety of fabrics and conducting a greater number of laundry cycles to approximate an average yearly number of laundry cycles is recommended. An expansion of this preliminary study should give more conclusive evidence of the trends observed.Originality/valueObjective measurement of drape and fabric mechanical properties related to drape after laundry treatments would assist the apparel manufacturer in developing laundry recommendations based on the fabric's performance and in selecting fabrics which maintain their drape characteristics, mechanical properties, and dimensional stability with use. Higher quality garments with increased consumer satisfaction would result.

The focus of this article of a three part series is the effects of preparation and composition on the shear rheology of cellulose in the ionic liquid 1-butyl-3-methylimidazolium chloride ([Bmim]Cl). Included are the effects of three different degrees of polymerization, (i.e., average molecular weight), manual versus high shear mixing, a range of cellulose concentrations, and the effects of controlled amounts of lignin and a hemicellulose. The rheology implies that a gel phase develops at higher degrees of polymerization, higher concentration, and at lower temperatures. The first article focused primarily on shear rheology of cellulose in [Bmim]Cl with a high shear preparation technique, one degree of polymerization, a narrow range of cellulose concentrations, and temperature. The third article focuses on elongational rheology of cellulose in [Bmim]Cl. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Recycled fibers are commonly used in dissimilar applications and one of the most important applications is sound absorption. Recycled fiber nonwovens currently are in greater demands in industries because of their advantages such as low cost, biodegradability, acceptable mechanical and physical properties, and so on. Sound absorption materials, renewable, and eco-friendly nonwovens have been developed using recycled cotton and polyester fibers. This research provides a contribution to the body of knowledge on the sound absorption properties of nonwovens using recycled fibers which contain cotton and polyester by means of spun-laid technique and provides a better understanding of the effects of a number of manufacturing processes on nonwovens noise control performance and also contributes to the wider adoption of nonwovens as sound absorbers. The sound absorption coefficients were measured according to ASTM E 1050 by an impedance tube method. The results revealed that the average of the sound absorption coefficients increased with the thickness of the nonwovens, but decreased with the nonwoven fabric density.

Cellulose, lignin, raw bagasse fiber, and extracted bagasse fibers chemically processed with different concentrations of sodium hydroxide solution and treatment time were measured by thermogravimetry analysis (TGA). The thermal characteristics of these fibers were determined by thermogravimetry (TG) and derivative thermogravimetry (DTG) profiles and analyzed based on the onset degradation temperature, peak rate of thermal decomposition, and residual weight. According to the observations from the experimental data from TGA and DTG profiles and literature reports, it was found that higher content of cellulose and lower content of lignin would result in higher onset degradation temperature, higher peak rate of decomposition, and lower residual weight. Statistical analysis of the onset decomposition temperatures, peak rate of weight loss, and residual weights of different extracted bagasse fibers showed that most of their values were significantly different. The three‐dimensional surface plots of onset decomposition temperature and peak rate of weight loss indicated that higher content of cellulose occurred in the bagasse fiber treated under the condition close to the region around 2 N NaOH for 2 hours or 1.5 N NaOH for 1.5 hours.

Lyocell fibers, a generic subclass of rayon fibers, are produced from cellulose dissolved in N-methylmorpholine oxide (NMMO). The lyocell solutions typically consist of blends of cellulose from similar low and high degree of polymerization (DP) dissolving pulps to achieve desired spinnability and fiber properties. The objective of this research was to determine if alternative lower value cellulose sources could be used as raw materials for lyocell by characterizing solutions made from these sources. Shear viscosity, which strongly affects spinning of fibers, of ten cellulose sources at four concentrations was compared to that of five industrial dissolving pulp standards with DPs from 670 to 1720. Bleaching, concentration, cellulose source, and their interactions had significant effects on shear viscosity. Kudzu, sugarcane bagasse, recycled, and thermomechanical cellulose pulps had higher viscosities than did the more highly processed hardwood and softwood. Bagasse was similar to the lowest DP dissolving pulp standard. Recycled and thermomechanical pulps were similar to the higher DP standard and bleaching affected the shearing behavior of these less pure pulps. Shear viscosity measurements were effective in determining differences among the pulps.

A neural network computing technique was proposed to predict fabric end-use. One hundred samples of apparel fabrics were selected and measured using the Kawabata KES-FB instruments. Instrumental data of the fabric properties and information on fabric end-uses, suitings shirts, and blouses, were input into a neural network software to train a multilayer perceptron model. The prediction error rate from the established neural network model was estimated by using a cross-validation method.

Rheological measurements were used to characterize the behavior of lyocell solutions, i.e., cellulose dissolved in N-methymorpholine-N-oxide. Cellulose sources included dissolving pulp, kraft pulp, sugar cane fibers, and kenaf fibers. The dominance of viscous behavior, G′ values, over elastic behavior, G″ values, is affected by cellulose concentration and molecular weight. At lower concentrations and degrees of polymerization (DP), dissolving pulp solutions show viscous, inelastic behavior at low frequencies. At higher concentration and DP, dissolving pulp solutions are more elastic at higher frequencies. Solutions prepared with kenaf and sugar cane fibers show similar properties to those using pure dissolving pulp, and comparisons suggest the molecular weight and/or the presence of other substances such as lignin in the cellulose from these alternative sources affect the rheology.

Polyester (PET) swatches are treated with an electrical discharge plasma of a reactive atmosphere (tetrachlorosilane) to graft chlorosilane groups, subsequently hydrolyzed to very hydrophilic hydroxysilane groups. The Kawabata evaluation system for fabrics (KES-FB), high resolution microscopy, and surface tension measurements are used to investigate the physical properties of the fabrics before and after plasma exposure. The results show that the surface parameters are considerably modified by the treatment.

White specks are undyeable, undeveloped fiber communities on dyed and finished cotton (Gossypium hirsutum L.) fabrics. These specks currently are not quantifiable for comparison purposes. In order to remove the subjectivity from dye defect classification, image analysis was evaluated as a means to accomplish white speck detection. Of the wide variety of imaging software that exists, the Optimas system was best suited for this application. Two sets of cotton fabrics were evaluated for their white speck content. One study involved eight plain-weave fabrics, each with visually distinct levels of white speck content. This study was used primarily to identify the system, software, and technique best suited for white speck quantification. The second study verified the system, software, and technique using 35 filling-face sateen fabrics. Compared with the eight fabrics, the 35 had subtle differences in white speck levels. The imaging system was consistent on several dates of testing.

This paper introduces a new way of classifying clothing fabrics objectively. Representative apparel fabrics were collected and measured by the Kawabata Evaluation System for Fabrics (KES‐FB). The disjoint clustering method was used to divide fabrics into four clusters, each representing particular fabric performance and end‐use characteristics. These classified clusters were further analyzed applying the method of principal‐component analysis to acquire factor patterns that indicate the most important fabric properties for characterizing different fabric end‐use. Extracted information from the instrumentally obtained data in terms of fabric physical properties is useful to fabric and garment producers, apparel designers, and consumers in specifying and categorizing fabric products, in insuring proper fabric use, and in controlling fabric purchase.

Bundles of fibers were extracted from the rind of sugar cane, and their feasibility for geotextile and textile applications was investigated as value-added agricultural waste by-products. Three distinct steps were used to obtain the ultimate product: mechanical separation, chemical extraction (retting), and steam explosion. The input variables for the process were considered: alkali concentration in solution (expressed as normality), reaction time, frequency of tumbling (expressed as the time interval between two successive tumbling sessions), volume of alkali solution, initial rinds mass, type of rind, and the presence of steam explosion. Statistical analysis of conducted experiments showed a complex dependency between the input variables and the final characteristics of the fiber bundles. Response surface models for lignin extraction, NaOH consumption, agitation factor and characteristics properties of the final fibers (length, weight and tex) were obtained considering normality of alkali solution, the reaction time, and the interval between two consecutive agitations. Polynomial models were used to optimize the process for obtaining fibers suitable for textile purposes.

Recycling of cotton (or rayon) cellulose as lyocell fibers is proposed based on the selective solubility of cellulose in organic N-oxides and the selective hydrolysis of polyesters in NaOH solutions. In the first step, the cotton component of a fabric made of 50/50 cotton/polyethylene terephthalate was separated from the polyester by basic hydrolysis of the latter in NaOH solutions. In the second step, the cellulose component from another sample of the same fabric was selectively dissolved in N-methyl morpholine monohydrate to form a 1-2% cellulose solution. It was then concentrated to a spinable 15-17% solution by dissolving the cotton separated in the first step. Lyocell fibers were subsequently spun at 85-90C using an advanced capillary extrusion rheometer system.

A large amount of the textile waste produced during the manufacturing of clothing and other textile products is polyester/cellulosic fabrics such as polyester/cotton and polyester/rayon blends. The possibility of using thermal methods such as thermogravimetric/differential thermal analysis (TG/DTA) and differential scanning calorimetry (DSC) to determine the efficiency of methods for separating cotton and polyester from fabrics made of intimately blended fibers was investigated. Both were confirmed as efficient methods for rapid estimation of the polyester content of blended fabrics.