In this search, the wool fabric was dyed with a natural dye Calligonum comosum (Callig. Co. dye); the dyeing process was applied under different conditions by changing dye bath temperature, time of dyeing, and pH of dye bath also using different mordants. Ultraviolet protection factor (UPF) was determined for each dyed wool sample. The role of these dying conditions on the via color strength analysis their effects on the reflectance spectra were investigated using the spectro-photometer tool, CIE tristimulus values, and the color parameters. The dye-ability strength and fastness to washing and perspiration properties of these wool samples dyed with (Callig. Co. dye) were carried out spectrophotometrically and evaluated the antimicrobial activity for blank and dyed wool fabrics via gram-positive and gram-negative was followed. The results showed that dyeing wool fabrics with (Callig. Co. dye) increased their protective abilities markedly, and they have effective protection against UV rays, also improving their antimicrobial activity. Moreover, Different conditions of the dye bath changed the optical properties noticeably. The present study will be useful for dermatologists advising patients regarding the UPF properties of clothes made from natural fabrics (wool) and dyed with natural colorants (Callig. Co. dye).
Tumble dryers are widely used for drying garments, but felting shrinkage can be caused to wool garments during the tumble drying process. To dry wool fabrics or garments in tumble dryers, the flat dry function has been introduced in the dryers; however, the energy efficiency is very low. The current study investigated fabric movement at different rotation speeds in the tumble dryer and their resultant performances in terms of specific moisture extraction rate, evenness of drying, fabric shrinkage, and fabric smoothness. For shrink-resist-treated wool fabrics, tumble drying at the rotation speed to keep fabric movement in projectile motion accompanied with occasional tumbling could achieve better energy efficiency, drying uniformity, and fabric smoothness. For untreated wool fabrics, introducing vertical movement to the flat dry in the tumble dryer can improve the heat exchange between the fabric and hot air, resulting in an increase in energy efficiency of approximately 30% compared with motionless flat drying. Wool fabric shrinkage can be controlled at less than 2% with the smooth appearance of fabric at grade 3.5 after drying under the recommended drying condition. This study could help tumble dryer manufacturers design optimal drying methods for wool fabrics with the potential for the reduction of energy consumption.
Durable and formaldehyde-free flame-retardant (FR) modification of wool fabric using phosphorous compounds is of great interest. In this study, Schiff base imine groups were firstly introduced onto wool fiber through aldehyde-amine condensation between p-hydroxybenzaldehyde and wool fiber. Then, an efficient and durable FR wool fabric was fabricated by incorporating diethyl phosphite (DEP) into a Schiff base intermediate via the Pudovik reaction. The potential reaction mechanism among p-hydroxybenzaldehyde, DEP and wool fiber was explored. The thermal stability, smoke generation ability, FR ability and washing durability of the modified wool fabric were studied. The FR modification significantly increased the thermal resistance of wool fabric and suppressed smoke generation by half. The wool fabric modified by 20 g/L DEP was able to self-extinguish during the burning test, suggesting the higher FR efficiency of the DEP-incorporated Schiff base system. The modified wool fabric still self-extinguished after 20 commercial launderings, which is attributed to the covalent grafting of DEP onto wool fiber. Char residue analyses revealed the condensed charring FR mechanism of the DEP-incorporated Schiff base system on wool. This work provides a novel approach to prepare efficient and durable FR functional wool fabric via the Schiff base reaction and Pudovik reaction among p-hydroxybenzaldehyde, DEP and wool fiber.
The compound 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) is an eco-friendly water treatment agent possessing flame-retardant phosphorus element and multi-carboxylic acid groups in its molecular structure. In the present work, PBTCA is employed as a finishing agent to improve the flame retardancy of the wool fabrics by the pad-dry-cure technique. The treated wool (10.2% weight gain) by 100 g/L of PBTCA showed an increased flame retardancy with a limiting oxygen index value (LOI) of 44% with a minimum char length of 40 mm. Importantly, the treated wool can self-extinguish after 30 washing cycles. The PBTCA-treated wool exhibited better stability with obviously increased char residue of 39.7% and 28.7% at 600 °C, while only 25.9% and 13.2% were measured for the control wool in nitrogen and air atmosphere, respectively. In addition, the high thermal stability of the treated wool with astonishing char-forming ability is confirmed by the SEM images of the wool after the isothermal heating treatment at different temperatures. Finally, a two-stage flame-retarding mechanism of enhanced crosslinking and char formability of PBTCA-treated wool is proposed and analyzed by infrared spectroscopy (TG-FTIR) and thermal (DSC and TGA) results of the pyrolytic volatiles of the treated wool.
Two forms of pollutants are usually discharged from scouring of wool fleece; namely the effluent liquid phase and the solid phase. These phases comprise a significant quantity of wool wax which would be a suitable candidate for valuable products and applications. This work is devoted to extraction, recovery, and characterization of lanolin from wool fleece from different sheep breeds to assign possible ways for its utilization in the textile field. The results show that the amount of wool wax extracted from coarse wool fleece as well as its chemical composition and physical properties are almost similar to those extracted from other finer wool fleece. The aim of this work is further devoted to separation and characterization of fatty acids (FAs) from the extracted wool wax. The separated wool FAs were esterified with poly ethylene glycol (PEG) to obtain a condensate which was utilized as a nonionic softener for wool. The alteration in morphology of the coated wool fabric was assessed using scanning electron microscopy. The results revealed that the WFA/PEG-coated fabrics exhibit reduced surface roughness and improved resistance to felting shrinkage during mechanical agitation.