Jawad Raza, Sumera Dero, Liaquat Ali Lund and Zurni Omar
The purpose of study is to examine the dual nature of the branches for the problem of Darcy–Forchheimer porous medium flow of rotating nanofluid on a linearly stretching/shrinking…
Abstract
Purpose
The purpose of study is to examine the dual nature of the branches for the problem of Darcy–Forchheimer porous medium flow of rotating nanofluid on a linearly stretching/shrinking surface under the field of magnetic influence. The dual nature of the branches confronts the uniqueness and existence theorem, moreover, mathematically it is a great achievement. For engineering purposes, this study applied a linear stability test on the multiple branches to determine which solution is physically reliable (stable).
Design/methodology/approach
Nanofluid model has been developed with the help of Buongiorno model. The partial differential equations in space coordinates for the law of conservation of mass, momentum and energy have been transformed into ordinary differential equations by introducing the similarity variables. Two numerical techniques, namely, the shooting method in Maple software and the three-stage Lobatto IIIA method in Matlab software, have been used to find multiple branches and to accomplish stability analysis, respectively.
Findings
The parametric investigation has been executed to find the multiple branches and explore the effects on skin friction, Sherwood number, Nusselt number, concentration and temperature profiles. The findings exhibited the presence of dual branches only in the case of a shrinking sheet.
Originality/value
The originality of work is a determination of multiple branches and the performance of the stability analysis of the branches. It has also been confirmed that such a study has not yet been considered in the previous literature.
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Zulfiqar Ali Raza, Aisha Rehman, Faiza Anwar and Naseer Ahmad
This study aims to investigate the effect of the copresence of ferrous (Fe2+) ions and sodium dodecyl sulfate (SDS) on the activity of an amylase enzyme during the desizing of…
Abstract
Purpose
This study aims to investigate the effect of the copresence of ferrous (Fe2+) ions and sodium dodecyl sulfate (SDS) on the activity of an amylase enzyme during the desizing of greige viscose fabric for potential industrial applications. The removal of starches is an essential step before processing the fabric for dyeing and finishing operations. The authors tend to accomplish it in eco-friendly and sustainable ways.
Design/methodology/approach
The experiments were designed under the Taguchi approach, and the results were analyzed using grey relational analysis to optimize the process. The textile properties of absorbency, reducing sugars, bending length, weight loss, Tegawa rating and tensile strength were assessed using the standard protocols. The control and optimized viscose specimens were investigated for certain surface chemical properties using advanced analytical techniques including scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA).
Findings
The results demonstrate that the Fe2+ concentration and process time were the main influencing factors in the amylolytic desizing of viscose fabric. The optimized process conditions were found to be 0.1 mm Fe2+ ions, 3 mm SDS, 80°C, 7 pH and 30 min process time. The copresence of Fe2+ ions and SDS promoted the biodesizing of viscose fabric. The SEM, Fourier transform infrared spectroscopy, XRD and TGA results demonstrated that the sizing agent has efficiently been removed from the fabric surface.
Practical implications
The amylase desizing of viscose fabric in the presence of certain metal ions and surfactants is a significant subject as the enzyme may face them due to their prevalence in the water systems. This could also support the biodesizing and bioscouring operations to be done in one bath, thus making the textile pretreatment process both economical and environmentally sustainable.
Originality/value
The authors found no report on the biodesizing of viscose fabric in the copresence of Fe2+ ions and the SDS surfactant under statistical multiresponse optimization. The biodesized viscose fabric has been investigated using both conventional and analytical approaches.
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Saima Habib, Farzana Kishwar, Zulfiqar Ali Raza and Sharjeel Abid
This study aims to present a sustainable approach in the natural dyeing of cellulose fabric followed by nanosilver finishing through a green crosslinker of citric acid for…
Abstract
Purpose
This study aims to present a sustainable approach in the natural dyeing of cellulose fabric followed by nanosilver finishing through a green crosslinker of citric acid for potential antibacterial surgical gown fabrication.
Design/methodology/approach
The nanosilver finish was reproduced using the chemical reduction method. The fabric dyeing was performed on a lab-scale dyeing machine, whereas silver nano-finishing through a pad-dry-cure approach. Citric acid was used as an eco-friendly crosslinker. The specimens were characterized for antibacterial activity, surface chemical, textile, color properties and finish release trend.
Findings
The results demonstrated the successful application of curcumin dye followed by silver nano-finishing. The resultant fabric exhibited appropriate textile, dyeing performance indicators, hydrophobic behavior and sustainable broad-spectrum antibacterial activity.
Practical implications
The prepared nanosilver-finished/curcumin-treated fabric expressed desirable properties for potential applications in the fabrication of surgical gowns.
Originality/value
The authors found no reports on an extensive examination of nanosilver finishing on the color parameters of curcumin-dyed cellulose fabric while retaining its textile and comfort properties for possible surgical gown fabrication.
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Saima Habib, Farzana Kishwar and Zulfiqar Ali Raza
The purpose of this study is to apply silver nanoparticles on the cellulosic fabric via a green cross-linking approach to obtain antibacterial textiles. The cellulosic fabrics may…
Abstract
Purpose
The purpose of this study is to apply silver nanoparticles on the cellulosic fabric via a green cross-linking approach to obtain antibacterial textiles. The cellulosic fabrics may provide an ideal enclave for microbial growth due to their biodegradable nature and retention of certain nutrients and moisture usually required for microbial colonization. The application of antibacterial finish on the textile surfaces is usually done via synthetic cross-linkers, which, however, may cause toxic effects and halt the biodegradation process.
Design/methodology/approach
Herein, we incorporated citrate moieties on the cellulosic fabric as eco-friendly crosslinkers for the durable and effective application of nanosilver finish. The nanosilver finish was then applied on the citrate-treated cellulosic fabric under the pad-dry-cure method and characterized the specimens for physicochemical, textile and antibacterial properties.
Findings
The results expressed that the as-prepared silver particles possessed spherical morphology with their average size in the nano range and zeta potential being −40 ± 5 mV. The results of advanced analytical characterization demonstrated the successful application of nanosilver on the cellulosic surface with appropriate dispersibility.
Practical implications
The nanosilver-treated fabric exhibited appropriate textile and comfort and durable broad-spectrum antibacterial activity.
Originality/value
The treated cellulosic fabric expressed that the cross-linking, crystalline behavior, surface chemistry, roughness and amphiphilicity could affect some of its comfort and textile properties yet be in the acceptable range for potential applications in medical textiles and environmental sectors.
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Saima Habib, Zulfiqar Ali Raza, Farzana Kishwar and Sharjeel Abid
This paper aims to develop an indigo-dyed denim fabric treated with a nanosilver colloid in the presence of a natural crosslinker of citric acid for possible surgical gown…
Abstract
Purpose
This paper aims to develop an indigo-dyed denim fabric treated with a nanosilver colloid in the presence of a natural crosslinker of citric acid for possible surgical gown fabrication applications.
Design/methodology/approach
A bleached denim fabric was dyed with the sustainable indigo dye followed by silver nanofinishing through citric acid crosslinking under the pad-dry-cure method. The prepared denim samples were analyzed for chemo-physical, textile, dyeing, antibacterial and finish release properties.
Findings
The results demonstrated that the comfort and textile characteristics of nanosilver-treated/indigo-dyed cellulosic fabric were affected due to the crosslinking, surface amphiphilicity and air permeability. These properties were, still, in the acceptable range for the fabrication of naturally dyed and antibacterial nanofinished denim gowns.
Practical implications
The dyeing of denim with synthetic dyes may cause harmful effects on the skin and health of the wearer, and the authors present an eco-friendly sustainable approach.
Originality/value
The authors used the fabric substrate, natural indigo dye and reducing/crosslinker agent of citric acid, all being bio-based, in the fabrication of antibacterial dyed fabric for health care garments.
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Abstract
Purpose
The paper aims to improve the protective and comfort properties of both woven and knitted acrylic fabrics by applying a hybrid waterborne polyurethane/fluorocarbon hydrophobic finish.
Design/methodology/approach
In this study, it was found that the transportation of water from fabrics is one of the important textile parameters. To improve this property, a polyurethane-based finish (Dicrylan BSRN®) and an oil- and water-repellent finish (Oleophobol ZSR®) were applied by using the pad-dry-cure method. After applying the finishes, the resultant fabric samples were investigated for various textile properties.
Findings
The application of Oleophobol ZSR® increased the absorbency time, indicating that the fabric became hydrophobic, whereas the application of Dicrylan BSRN® finish improved the moisture management properties of the woven acrylic. The tensile strength of the woven acrylic fabric was not significantly affected by the application of these finishes. The contact angle of treated knitted fabrics increased and air permeability decreased with an increase in the concentration of Oleophobol ZSR®.
Practical implications
Moisture management is one of the crucial performance criteria in today’s apparel industry. Therefore, fluorochemicals are one of the major precursors used in water-repellent finishes and waterproof membranes in outdoor garments. Based on this fact, this research work focused on the textile sector, where moisture management is required.
Originality/value
This is the first report about the combined application of waterborne polyurethane and fluorochemical-based finishes on acrylic fabrics to tune their comfort and hydrophobic properties.
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Zulfiqar Ali Raza, Faiza Anwar and Sharjeel Abid
Chitosan is widely considered as a natural polymer and a diverse finish to impart antibacterial property and enhanced dye uptake of textiles. Herein, the authors have investigated…
Abstract
Purpose
Chitosan is widely considered as a natural polymer and a diverse finish to impart antibacterial property and enhanced dye uptake of textiles. Herein, the authors have investigated the feasibility of using chitosan/starch blend as a thickener in screen printing of cellulosic fabrics with some natural dyes.
Design/methodology/approach
The polymeric blend of chitosan/starch was prepared and used as a thickener for screen printing with three natural dye extracts, namely, Curcuma tinctoria (turmeric), Beta vulgaris (beet) roots and Lawsonia alba (henna) leaves on cellulosic fabrics like cotton and viscose. The viscosity and rheological properties of print paste as a fresh and after overnight shelving were examined. The influence of polymeric blends on cellulosic fabrics' print properties was inspected by determining their colorfastness, rubbing fastness, tensile strength and antibacterial activity.
Findings
The results depicted that chitosan/starch blend as printing thickener increased the shade depth with good wet and dry rubbing fastness for all the test natural dyes. The antibacterial activity of resultant printed cellulosic fabrics was found to be satisfactory against broad-spectrum bacterial strains.
Practical implications
This study's outcome is the development of chitosan blend thickeners to print the cellulosic fabrics with indigenous natural dyes.
Originality/value
The authors found no previous report on the synthesis of chitosan-based antibacterial blend thickeners with three distinct natural dyes and their application in screen printing of native and regenerated cellulosic fabrics of cotton and viscose, respectively.
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Zulfiqar Ali Raza, Faiza Anwar, Irshad Hussain, Sharjeel Abid, Rashid Masood and Hafiz Shahzad Maqsood
This study aimed to present fabrication of novel poly(lactic acid) (PLA) mediated chitosan nanoparticles (CNPs) and their impregnation on cotton fabric for enhanced antibacterial…
Abstract
Purpose
This study aimed to present fabrication of novel poly(lactic acid) (PLA) mediated chitosan nanoparticles (CNPs) and their impregnation on cotton fabric for enhanced antibacterial and physical properties.
Design/methodology/approach
The PLA-CNPs were characterized using scanning electron microscopy, energy dispersive x-ray spectroscopy, Fourier transform infrared (FTIR) spectroscopy and zeta size analysis. The prepared PLA-CNPs were impregnated on cotton fabric via pad-dry-cure method. The finished cotton fabric was then characterized for its antibacterial activity, functional and other physical textile properties.
Findings
The spectral and optical properties demonstrate that the NPs expressed spherical morphologies with an average particle diameter of 88.02 nm. The antibacterial activity of treated fabrics ranged between 75 and 90 per cent depending on the concentration of PLA-CNPs.
Practical implications
Because of enhanced awareness and desire for ecofriendly products, the use of sustainable and functional textiles is increasing day by day. For the said purpose, industries are using different chemical treatments to achieve desired end functionality. Currently, different synthetic antibacterial agents are in practice, but they lack sustainable approach to save the environment. In this study, the researchers have developed PLA mediated CNPs for sustainable antibacterial and physical properties of treated cotton fabric.
Originality/value
To the best of the authors’ knowledge, this is first attempt to fabricate PLA-incorporated CNPs for application on cotton fabric followed by a detailed characterization.
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Saima Habib, Zulfiqar Ali Raza, Farzana Kishwar and Sharjeel Abid
Present study aimed to nanosilver-treat some commercially dyed denim fabric using an eco-friendly cross-linker of citric acid for possible application in the fabrication of…
Abstract
Purpose
Present study aimed to nanosilver-treat some commercially dyed denim fabric using an eco-friendly cross-linker of citric acid for possible application in the fabrication of sustainable antibacterial and nontoxic surgical gowns.
Design/methodology/approach
The conventional untreated surgical gowns are prone to bacterial attack making them unprotective and infection carriers. Thereby, nanosilver finishing of the surgical-grade dyed denim fabric was achieved via citrate cross-linking under the pad-dry-cure method. The hence treated denim fabrics were characterized for surface chemical, crystalline, textile, color and antibacterial attributes using both conventional and advanced analytical approaches.
Findings
The results expressed that the prepared denim specimens contained surface roughness at the nanoscale besides some alterations in their textile and color parameters. Both textile and comfort properties of the finished fabric remained in the acceptable range with effective antibacterial activity.
Practical implications
The silver nano-finished dyed denim expressed broad-spectrum antibacterial activity and qualified as a potential substrate in the fabrication of surgical gowns. Such sustainable application of nanosilver finishing could be perused for industrial implications.
Originality/value
This study presents citric acid as a crosslinking agent to impregnate the commercially dyed denim fabric for potential application in the fabrication of surgical gowns. The application of nanosilver on prior citrated dyed-grown fabrics could be a novel approach. This study used approximately all the reagents and auxiliaries as bio-based to ensure the nontoxicity and sustainability of the resultant fabric.
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Abdul Lateef, Zulfiqar Ali Raza, Muhammad Aslam, Muhammad Shoaib Ur Rehman, Asma Iftikhar and Abdul Zahir
This study aims to fabricate multiwalled carbon nanotubes (MWCNTs)-mediated polyvinyl alcohol (PVA) composite films using the solution casting approach.
Abstract
Purpose
This study aims to fabricate multiwalled carbon nanotubes (MWCNTs)-mediated polyvinyl alcohol (PVA) composite films using the solution casting approach.
Design/methodology/approach
The prepared films were evaluated for diverse structural, surface, optical and electrical attributes using advanced analytical techniques, i.e. electron microscopy for surface morphology, Fourier transform infrared spectroscopy for tracing chemical functionalities, x-ray diffraction (XRD) for crystal patterns, water contact angle (WCA) analysis for surface wettability and UV visible spectroscopy for optical absorption parameters. The specimens were also investigated for certain rheological, mechanical and electrical properties, where applicable.
Findings
The surface morphology results expressed a better dispersion of MWCNTs in the resultant PVA-based nanocomposite film. The XRD analysis exhibited that the nanocomposite film was crystalline. The surface wettability analysis indicated that with the inclusion of MWCNTs, the WCA of the resultant nanocomposite film improved to 89.4° from 44° with the pristine PVA film. The MWCNTs (1.00%, w/w) incorporated PVA-based film exhibited a tensile strength of 54.0 MPa as compared to that of native PVA as 25.3 MPa film. There observed a decreased bandgap (from 5.25 to 5.14 eV) on incorporating the MWCNTs in the PVA-based nanocomposite film.
Practical implications
The MWCNTs’ inclusion in the PVA matrix could enhance the AC conductivity of the resultant nanocomposite film. The prepared nanocomposite film might be useful in designing certain optoelectronic devices.
Originality/value
The results demonstrated the successful MWCNTs mediation in the PVA-based composite films expressed good intercalation of the precursors; this resulted in decreased bandgap, usually, desirable for optoelectronic applications.