Investigating the Synthesis and Characterization of a Novel “Green” H₂O₂-Assisted, Water-Soluble Chitosan/Polyvinyl Alcohol Nanofiber for Environmental End Uses

The present work highlights the formation of a novel green nanofiber based on H2O2-assisted water-soluble chitosan/polyvinyl alcohol (WSCHT/PVA) by using water as an ecofriendly solvent and genipin used as a nontoxic cross-linker. The 20/80 blend ratio was found to have the most optimum uniform fiber morphology. WSCHT retained the same structure as WISCHT. The prepared nanofibers were characterized by Scanning electron microscopy (SEM), Fourier transform spectroscopy (FTIR), Thermo gravimetric analysis (TGA), Differential scanning calorimeter (DSC), X-ray diffraction (XRD), Water Contact Angle (WCA) and Ultraviolet-visible spectroscopy (UV-vis). During electrospinning, the crystalline microstructure of the WSCHT/PVA underwent better solidification and after cross-linking there was an increase in the melting temperature of the fiber. Swelling ratio studies revealed noticeable increase in hydrophilicity with increase of WSCHT, which was further demonstrated by the decrease of contact angle from 64.74° to 14.68°. WSCHT/PVA nanofiber mats exhibit excellent UV blocking protection with less than 5% transmittance value and also showed improved in vitro drug release properties with stable release for longer duration (cross-linked fibers) and burst release for shorter duration (uncross linked) fibers. Finally our experimental data demonstrates excellent adsorption ability of Colour Index (C.I.) reactive black 5 (RB5) due to protonated amino groups

Organic Silicone Based Poly-Acrylate Binder Synthesis for Textile Pigment Printing

This present study deals about an organic silicone based poly-acrylate binder by using Emulsion Polymerization technique because it produces high molecular weight polymers, and there is no or negligible content of volatile organic compounds (VOC) for textile pigment printing. The binder was prepared by polymerizing hard monomers, soft monomers, functional monomers, and compound emulsifying agent, organic silicone, an initiator, pH adjustor and deionized water. Then the properties like sublimation test, durability test, fastness test, yellowness and softness testing were performed. The role of acrylic acid and Methyl methacrylate on the characterization of the polymers was detected and recorded. A material has been selected based on pervious study of different research and effect of silicone amount on film was observed

Investigation on the Thermo-Regulating Fabric by Using Phase Change Material for Modern Textile Practical Application

Phase change materials (PCM) which can store energy and increased thermal properties of fabric applied on over a narrow temperature range. It is antiphonal to temperature change by absorbing or releasing heat which is potential for human skin. PCM for Thermal Energy Storage (TES) are materials supplying thermal regulation and change particular phase in temperatures by absorbing and emitting medium condition heat. Polyethylene glycol (PEG-1000) is used as PCM in this experiment and we took a 2.5% concentration that was encapsulated by using an in-situ polymerization technique. PEG microcapsules are verified by measuring FTIR analysis and DSC studies. The heat storage capacity of 2.5% PEG coated fabric was determined to be 2842.5120 J/g and for binder coated fabric 1557.8 J/g by DSC analysis and FT-IR analysis of PEG microcapsules exhibited the highest peak at 3400-2400cm−1 this is the characteristic absorption peaks of –OH stretching vibrations and we got average stiffness values for binder coated is 0.49 (warp wise) and 0.57(weft wise) and for 2.5% PEG coated is 0.71(warp wise) and 0.98(weft wise).  After that the treated fabrics were characterized with respect to their morphology and the laundering durability testing of 5 and 10 cycles was evaluated for practical use. In this paper we investigated about cooling effect of Fabric by using 2.5%. PCMs via the storage of latent heat by producing microcapsules showed higher thermal energy amount, than the binder coated fabric

New Sustainable Approach for the Production of Fe3O4/Graphene Oxide-Activated Persulfate System for Dye Removal in Real Wastewater

Persulfate (PS)-activated, iron-based heterogeneous catalysts have attracted significant attention as a potential advanced and sustainable water purification system. Herein, a novel Fe3O4 impregnated graphene oxide (Fe3O4@GO)-activated persulfate system (Fe3O4@GO+K2S2O8) was synthesized by following a sustainable protocol and was tested on real wastewater containing dye pollutants. In the presence of the PS-activated system, the degradation efficiency of Rhodamine B (RhB) was significantly increased to a level of ≈95% compared with that of Fe3O4 (≈25%). The influences of different operational parameters, including solution pH, persulfate dosage, and RhB concentration, were systemically evaluated. This system maintained its catalytic activity and durability with a negligible amount of iron leached during successive recirculation experiments. The degradation intermediates were further identified through reactive oxygen species (ROS) studies, where surface-bound SO4− was found to be dominant radical for RhB degradation. Moreover, the degradation mechanism of RhB in the Fe3O4@GO+K2S2O8 system was discussed. Finally, the results indicate that the persulfate-activated Fe3O4@GO catalyst provided an effective pathway for the degradation of dye pollutants in real wastewater treatment

Electrolyte influence on sorption behaviours of Direct Blue 71 dye on ramie fibre

Ramie loose fibre was dyed using Direct Blue 71 dye at 70, 80, 90 and 100°C without and with NaCl electrolyte in order to investigate the distinction of dye sorption behaviours. The results show that the dye exhaustion increases with addition of NaCl and shortens the equilibrium dyeing time. The dye adsorption process of dyeing without and with NaCl followed pseudo second-order kinetics, but the rate constant of sorption is larger for the latter compared to the former

Effluent-free deep dyeing of cotton fabric with cacao husk extracts using the Taguchi optimization method

Textile dyehouses are under scrutiny because they discharge colored and hazardous effluents to waterways. There is a need to develop an alternative dyeing system that does not produce any hazardous effluent. The waterless dyeing method could be a viable eco-friendly alternative to the traditional aqueous dyeing method. In this work, cacao husk extracts were used as a natural dye in the decamethylcyclopentasiloxane (D5) medium for the dyeing of cotton fabric, and subsequently, the dyed cotton was treated by a fixation treatment with a cationic dye-fixing agent in the D5 medium. The cotton fabric dyed with cacao husk extracts exhaustion in the waterless D5 medium exhibited better exhaustion, fixation rate, color strength (K/S), and colorfastness to washing and rubbing compared to the fabric dyed with the same extracts using the conventional aqueous dyeing and dye-fixing methods. The dye exhaustion percentage and the dye fixation rate were 95.6% and 94.8% in the D5 medium respectively, which is significantly higher in comparison to a 48.2% dye exhaustion percentage and a 35.3% dye fixation rate in the conventional water medium. An orthogonal array design (L9) was adopted to optimize the dyeing conditions with respect to exhaustion percentage. The results indicated that the dyebath temperature was the most important factor for achieving the optimal dye exhaustion, and dyeing time also showed considerable effects. Linear regression was used to predict the exhaustion percentage, and the resulting p value of 0.000 demonstrated that a strong coefficient was proven among all selected factors. This study has demonstrated that dyeing of cotton fabric with cacao husk extracts in the D5 dyeing system can be a viable method for the textile industry with minimal environmental pollution

The Influence of Annealing Process on Crystallinity and Structural Properties of Cotton/Spandex Fabric

This research aims to elucidate the crystallinity, structural and mechanical properties of cotton/spandex knitted fabric after conducting heat setting i.e., annealing process with optimized condition for the first time. Experimental results disclosed that, crystallinity index (CI) (%) of heat-treated cotton/spandex were increased with increased temperature and also mechanical properties i.e., tensile strength was improved as the temperature rose from 120 to 140°C and decreased with augmenting temperature ranges, which is in good agreement with the findings of CI % through X-ray diffraction (XRD) patterns. The attendance of cellulose dehydration was further confirmed by Fourier transform infrared (FT-IR) spectra in order to observe the structural integrity

Adsorption, kinetics, and thermodynamic studies of cacao husk extracts in waterless sustainable dyeing of cotton fabric

Natural dyes exhibit a low dye uptake when cellulosic fiber dyeing is carried out using a conventional water bath dyeing process. In this research, cotton fabric was exhaust dyed in a microemulsion dyebath containing cacao husk extracts dye and decamethylcyclopentasiloxane (D5) to achieve higher dye exhaustion percentage on cotton fiber, which is an environmentally beneficial dyeing process. The adsorption behavior of cacao husk extract dye in a D5 microemulsion system was investigated under conditions of varied dye mass (1–8% o.w.f), dyeing time (5–500 min), and dyeing temperatures (333–373 K). Kinetic modelling of cacao husk extracts dye/D5 adsorption on cotton fiber was studied by fitting experimental data to pseudo first-order and pseudo second-order kinetics, and the intraparticle diffusion model. Early results indicated that the kinetic model of adsorption of cacao husk extracts dye on cotton fiber followed the pseudo second-order model. Langmuir, Freundlich, and Dubinin–Radushkevich adsorption isotherm models were employed to analyze the adsorption isotherms, and the results showed that the adsorption process fit well with the Langmuir model compared to the Freundlich isotherm. The mean adsorption energy from the Dubinin–Radushkevich isotherm model implied that adsorption of the cacao husk extracts onto cotton was accompanied with a physical process. The values of standard enthalpy (ΔH° > 0), standard entropy (ΔS° > 0), and Gibbs free energy (ΔG° < 0) strongly reflected that the adsorption of the cacao husk extracts onto cotton was thermodynamically favourable and feasible. Thus, waterless dyeing of cotton fabric using a natural dye/D5 system explores a sustainable dyeing technology with higher dye exhaustion percentage

Influence of Sequential Liquid Ammonia and Caustic Mercerization Pre-Treatment on Dyeing Performance of Knit Cotton Fabric

A two-stage sequential pretreatment including caustic mercerization (CM) and liquid ammonia (LA) treatment was applied to investigate the influence on dyeing performance and handle of knit cotton fabric, and the relationship between dye size and dyeing properties. Various techniques were applied to characterize all the treated fabrics. X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) analyses of the treated fabrics confirmed that both sequential treatments decreased the crystallinity of cotton fabric more than only the CM or LA treatment. The pattern of cellulose I was transferred to a mixed configuration of cellulose II and cellulose III after the CM/LA or LA/CM treatment. Thermal performances measured by thermogravimetric analysis (TGA) and differential thermogravimetry (DTG) techniques showed that the thermal stability of the treated cotton only marginally decreased. The wicking height increased after the sequential CM/LA treatment, indicating that the hydrophilicity of the fabric increased. The dye absorption and color uniformity were better for the reactive dye with a smaller molecular weight (Reactive Red 2) compared with the one with a larger molecular weight (Reactive Red 195). The total dye fixation efficiency (T%) increased to 72.93% and 73.24% for Reactive Red 2 dyeings of CM/LA- and LA/CM-cotton fabric from 46.75% of the untreated fabric, respectively; the T% increased to 65.33% and 72.27% for Reactive Red 195 dyeings of CM/LA- and LA/CM-cotton fabric from 35.17% of the untreated fabric, respectively. The colorfastness and dye exhaustion and fixation percentages of the samples were enhanced after the treatments. Furthermore, compared to the single CM or LA treatment, the softness handle properties were further improved after the fabrics were sequentially treated by CM/LA. The developed pre-treatment of CM/LA can be used in the textile industry to promote the dyeability, handle, and mechanical properties of knit cotton fabrics

The optimisation of whiteness of polyester fabric treated with nanoparticles of 2,2′-(vinylenedi-p-phenylene)bis-benzoxazole (OB-1) by the Taguchi method

This study explores a new approach to achieve a whitening effect on polyester fabric by utilizing a ground form of raw OB-1 (OB-1-G) in combination with dispersing agents. The whitening process parameters, such as whitening temperature, OB-1-G mass, and whitening time were optimized using the L16 orthogonal array-based Taguchi methodology. The signal-to-noise ratio was carried out through a larger-is-better approach to augment the parameter responses, specifically the whiteness. The results suggest that the degree of whiteness of polyester fabric is significantly affected by the whitening treatment temperature (P < 0.05), with a contribution percentage of 93.87%. A whiteness index of 94.12 was achieved for the polyester fabric treated at the optimized conditions. The fabric treated with OB-1-G at the optimized conditions was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The investigation also included the correlation between the length of time spent in washing and rubbing, and their efficacy in achieving whitening outcomes. The research demonstrated the effectiveness of OB-1-G nanopowder in combination with dispersing agents as a fluorescent optical brightener for the optical brightening of polyester fiber with potential use in the textile industry on a larger scale