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The purpose of this work is to investigate the correlation characteristics in mechanical, thermal and optical properties of PMMA‐acrylic polyol polymer blends mixed with lawsone natural dye for coating paint application.

Natural brownish dye colorant was extracted from Lawsonia Inermis leaves used as a dye colorant in this paint coating system by using ethanol as the solvent. Poly(methyl methacrylate) (PMMA), blended with acrylic polyol was used as the binder system. The ratio of PMMA to acrylic polyol was varied with PMMA dominance. The dye colorant was fixed at 10 wt percent.

The potential time measurement tests showed that the dye colorant paint system with 10 wt percent of acrylic polyol has the highest coating resistance against electrolyte penetration. The dye colorant paint system with 30 wt percent acrylic polyol performed better in mechanical tests such as cross‐hatch and impact resistance. The dye colorant paint system molecular crosslinks were analysed by using the fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction spectroscopy.

The ratio of lawsone dye colorant in the polymer blends is found limited to 10 percent. Increasing in the percentage of lawsone dye colorant will cause inhomogeneity in coating paint sample.

A new formulation of natural dye colorant paint system with 10 percent wt dye volume concentration of lawsone as pigment was obtained.

The purpose of this study is to highlight the threats related to the utilization of synthetic fibers. Volatile organic compounds, particulates and acid gases are released during the production of polyester and other synthetic textiles. Polyester is problematic solid waste material as it takes centuries to break down and hence causes microplastic pollution. Biodegradable synthetic solutions for the replacement of polyester are a sustainable business marketing these days. The naNia fiber is the breakthrough product and it is claimed a biodegradable, compostable and toxin-free polymer.

In this research, fabric constructed of naNia fiber was dyed with the extract of naturally occurring Lawsonia inermis (henna) plant leaves. The henna dye was extracted in water and ethanol using different methods, and the better extract was selected by the evaluation of ultraviolet-visible spectroscopy and phytochemical analysis. Henna with ethanol extract showed more desirable results hence it was selected to dye naNia fabric. To improve dyeability, premordanting, simultaneous mordanting and postmordanting were done using chitosan, fresh lemon extract and tannic acid, respectively. The dyed fabric samples were subjected to color strength analysis and multiple colorfastness tests.

The colorfastness test has shown good to excellent results. Scanning electron microscope analysis had also shown the attachment of dye molecules to the filaments. This study revealed that henna dye is appropriate to color naNia fiber even without the aid of a mordant.

For the first time, toxicant-free, biodegradable polyester (naNia) is successfully dyed with sustainable and naturally available dyes and mordants.

This study aims to study electrochemically and by weight-loss experiments the effect of UAE Rhazya Stricta Decne extract on the corrosion inhibition of mild steel in 1.0 M HCl solution, which will serve researchers in the field of corrosion.

Weight loss measurements were carried out on mild steel specimens in 1.0 M HCl and in 1.0 M HCl containing various concentrations (ranging from 2.0 to 0.002 g/L.) of the UAE Rhazya Stricta Decne extract at temperatures ranging from 303 to 343 K.

The aqueous Rhazya Stricta Decne leaves extract was found to be a highly efficient inhibitor for mild steel in 1.0 M HCl solution, reaching about 90 per cent at 2.0 g/L and 303 K, a concentration considered to be very moderate. Even with one-tenth of that concentration, 0.2 g/L, an inhibition of about 82 per cent was obtained at 303 K. The rate of corrosion of the mild steel in 1.0 M HCl is a function of the concentration of the Rhazya Stricta Decne extract. This rate increases as the concentration of the Rhazya Stricta Decne extract is increased. The percentage of inhibition in the presence of this inhibitor was decreased with temperature which indicates that physical adsorption was the predominant inhibition mechanism because the quantity of adsorbed inhibitor decreases with increasing temperature.

This inhibitor could have application in industries, where HCl solutions at elevated temperatures are used to remove scale and salts from steel surfaces, such as acid cleaning of tankage and pipeline, and may render dismantling unnecessary.

This paper is intended to be added to the family of green corrosion inhibitors which are highly efficient and can be used in the area of corrosion prevention and control.

The paper reports an investigation into the use of aqueous extracts of rice bran as a green inhibitor for corrosion of carbon steel in hydrochloric acid (HCl) solution.

Extracts from the rice bran were used as the main component of an environmentally friendly corrosion inhibitor for use in HCl pickling processes. Inhibition behavior on carbon steel in HCl was investigated by means of mass‐loss tests, polarization curves, electrochemical impedance spectroscopy and atomic force microscopy.

The results show that the extract exhibited good inhibition performance in 1 M HCl. The inhibition efficiency increased with increase in the concentration of the inhibitor and was only moderately affected by temperature variations in the range 303‐363 K. The inhibitive action was due to adsorption on the A3 steel and the adsorption process was consistent with the Langmuir isotherm. The free energy of adsorption (ΔG_ads.) was −4.192 kJ/mol. The negative value of ΔG_ads. indicated spontaneous adsorption of the inhibitor occurred on the surface of A3 steel.

Rice bran extract is an effective inhibitor and can be used to protect carbon steel from corrosion in HCl solution.

The rice bran extracts are an effective green inhibitor and can be widely used in the pickling of metals.

The textile industry is evolving toward nanotechnology, which provides materials with self-cleaning properties. This paper aims to provide a thorough explanation of the green synthesis and mechanism of ZnO nanoparticles, with prospective applications of zinc oxide nanoparticles (ZnO NPs) in self-cleaning textiles.

This review introduces a green mechanism for the synthesis of ZnO NPs using plant extracts, their self-cleaning properties and the mechanisms of physical, chemical and biological self-cleaning actions for textile applications.

ZnO NPs are among the several nanoparticles that are beneficial for self-cleaning textiles because of their exceptional physical and chemical properties, although review publications addressing the use of ZnO NPs in textiles for self-cleaning are uncommon. These results indicate that the plant-synthesized ZnO NPs display excellent biological, physical and chemical self-cleaning properties, the mechanism of which involves photocatalysis, surface roughness and interactions between ZnO NPs and bacterial surfaces.

Nanoformulations of plant-synthesized ZnO have been reviewed to achieve promising self-cleaning textile properties and have not been reviewed earlier.

Natural colorants are believed to be safe because of their nontoxic, noncarcinogenic and biodegradable nature, and also, the demand for natural dyes is steadily increasing. This study aims to investigate the dyeing of polyethylene terephthalate (PET) fabrics under cold plasma and ultraviolet (UV) radiation conditions with Prangos ferulacea.

In the first, some PET fabrics were modified using UV radiation and some others by cold plasma (oxygen/argon), and then the dyeing of fabrics with the natural dye was done (100°C/130°C) without using metallic mordant. Dyeability (color strengths) of the treated samples, colorfastness to washing, light and rubbing, water absorption time, crease recovery angle, air permeability and mechanical behavior were investigated.

The maximum color strength (k/s = 4.87) was achieved for the fabric exposed to UV radiation for 2 h and then dyed with Prangos ferulacea at 130 °C. The results indicated that the dyed fabric showed acceptable colorfastness (very good–excellent) properties in washing and rubbing fastness except for colorfastness to light (moderate). The strength and the angle of crease recovery of treated and dyed samples have increased, while the time of water absorption and air permeability have decreased.

The surface modification of PET (UV radiation and plasma treatment) provides a new idea to improve the dyeability of PET with Prangos ferulacea natural dye without using metallic mordant.

This paper aims to develop a new method of protein detection in fabric using purified henna extract targeted to be used as a precautionary step by protein contact dermatitis (PCD) patients.

Henna contains lawsone, which is known for its reaction with amino acid, resulting in the formation of a highly coloured compound. Dye exhaustion test of 2 per cent purified henna extract was done on both protein and non-protein fabric, and the results were analysed using independent samples t-test to assess the significant differences of the comparison. Then, protein fabric indicator was developed by incorporating purified henna extract. It was tested for its dye ability and stability.

Protein fabrics showed a significant higher dye exhaustion (p = 0.001) in which pure silk came in first with 21.70 per cent ± 2.53, silk/rayon, 13.96 per cent ± 0.55, viscose/wool, 9.57 per cent ± 1.36, cotton/spandex, 5.89 per cent ± 0.86, linen/cotton, 5.26 per cent ± 1.29, cotton, 4.87 per cent ± 1.51, polyester/viscose, 4.69 per cent ± 1.09, linen, 4.56 per cent ± 0.86, polyester/cotton, 3.90 per cent ± 0.29 and polyester and 3.88 per cent ± 0.66. Two different forms of protein fabric indicator were developed: capsule and tablet. Both indicators showed good observable dye exhaustion and fixation results. Orange henna dye was fixed on protein fabric while non-protein fabric returned to its original colour after washing procedure. However, the tablet form showed better performance in terms of functionality and stability.

This study will help general community to better understand fibre and its constituents, especially protein where clothing is an integral part of human life because it comes in direct contact with the human skin. As PCD caused by clothing and textile is an uncommon disease, it may also help in creating awareness on how some people may develop contact dermatitis through fabric. This is because the fabric’s protein content is a causative allergen, which most people tend to overlook. For the researcher, this study helps to elucidate some critical areas in PCD for clothing and textile as this topic can be considered an understudy. There is no standard method to detect protein in fabric, especially blended fabric. Thus, a portable kit to detect protein in fabric will be developed in this study. This kit will benefit PCD patients to ease them in finding the right fabric for their skin.

The paper aims to investigate the feasibility of developing natural dyes from the barks of Araucaria columnaris and leaves of Macaranga peltata, Averrhoa bilimbi. The paper also deals with the application of natural dyes in textile coloration.

Dye extraction was carried out using the aqueous method. The dyeability of the aqueous extract was assessed on cotton, silk and polyester yarns using different mordants (alum, acetic acid, CuSO₄, lemon juice) and without mordant. UV–Visible spectral analysis and pH of different natural dyes were determined. Percent absorption, K/S values, CIELab values and fastness properties of the selected dyed yarns were also assessed.

The percentage values for dye exhaustion differed with various mordants. The K/S values were found to be influenced by the addition of mordants. Different hues were obtained with the usage of different mordants. Fastness results exhibited good to very good grades.

The effective application of aqueous method of dye extraction in the study avoids solvent toxicity. The current results proved that the dyeing could be achieved at room temperature for different yarns (cotton, silk, polyester). At present, no report exists in the literature of research work on the extraction of natural dyes from the leaves of M. peltata, A. bilimbi and their dyeing potential on cotton, silk and polyester.

The present work offers new environment-friendly dye as well as simple dyeing method. Barks and leaves are promising sources of dye. Enormous availability of barks and leaves avoids the exploitation of the plant parts for the extraction of natural dyes.

The important feature of this study was the effective dyeing of natural and synthetic fibers at room temperature. The novel sources of natural dyes would contribute significantly to the existing knowledge of dyeing, and the natural dyes reduce the environmental impact of synthetic dyes.

The purpose of this paper is to validate the antimicrobial activity (both antibacterial and antifungal) of in vivo and in vitro ethanolic anthocyanin extracts of Clitoria ternatea L. (vivid blue flower butterfly-pea) and Dioscorea alata L. (purple yam) against selected bacteria (Bacillus subtilis, Staphylococcus aureus and Escherichia coli) and fungi (Fusarium sp., Aspergillus niger and Trichoderma sp.).

The freeze-dried samples (0.2 g) from in vivo vivid blue flowers of C. ternatea L. were extracted using 10 mL ethanol (produced ethanolic red extraction) and 10 mL distilled water (produced aqueous blue extraction) separately. Two-month-old in vitro callus samples (0.2 g) were only extracted using 10 mL ethanol. The anthocyanin extractions were separated with the addition (several times) of ethyl acetate and distilled water (1:2:3) to remove stilbenoids, chlorophyll, less polar flavonoids and other non-polar compounds. Furthermore, the antimicrobial properties were determined using agar diffusion technique. Three bacteria (B. subtilis, S. aureus and E. coli) and fungi (F. sp., A. niger and T. sp.) were streaked on bacteria agar and dextrose agar, respectively, using “hockey stick”. Then, the sterile paper discs (6 mm diameter) were pipetted with 20 µL of 1,010 CFU/mL chloramphenicol (as control for antibacterial) and carbendazim (as control for antifungal) in vivo and in vitro extracts. The plates were incubated at room temperature for 48 h, and the inhibition zones were measured.

Based on the results, both in vivo and in vitro ethanolic extracts from vivid blue flowers of C. ternatea L. showed the best antibacterial activity against the same bacteria (B. subtilis), 11 and 10 mm inhibition zones, respectively. However, different antifungal activity was detected in in vitro ethanolic callus extract (12 mm), which was against T. sp., contrary to in vivo ethanolic extract (10 mm), which was against F. sp.; antibacterial activity of D. alata L. was seen against the same bacteria (E. coli) with the highest inhibition zone for in vivo extract (8.8 mm), followed by in vitro extract (7.8 mm).

Anthocyanins are responsible for the water soluble and vacuolar, pink, red, purple and blue pigments present in coloured plant pigments. These pigments (pink, red, purple and blue) are of important agronomic value in many crops and ornamental plants. However, anthocyanins are not stable and are easy to degrade and fade whenever exposed to light.

Plant extracts containing bioactive agents with antimicrobial properties have been found to be useful in treating bacterial and fungal infections, as well as showed multiple antibiotic resistance.

Both in vivo and in vitro extracts from vivid blue flower petals (C. ternatea L.) and purple yam (D. alata L.) have important applications as natural antimicrobial (antibacterial and antifungal) agents in the coating industry, instead of natural pharmaceutical products.

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.

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.

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.

This study's outcome is the development of chitosan blend thickeners to print the cellulosic fabrics with indigenous natural dyes.

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.