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Copolymer resins of peanut skin tannin extract, aldehydes and cashew nut shell liquid were prepared. The resins were blended with bitumen and used in formulating oleoresinous wood varnishes. The film properties of the varnishes were determined and the results showed that the gloss and scratch hardness of the films increased with increase in the quantity of cashew nut shell liquid/tannin‐aldehyde resins incorporated. The results also showed that the resins improved the chemical resistance of the varnish films. Varnish compositions containing 50:50 of bitumen and the resins gave films with satisfactory physical and chemical properties. The study showed that it is possible to formulate excellent oleoresinous wood varnishes using blends of bitumen and cashew nut shell liquid/tannin‐aldehyde resins.

Describes experiments with the use of coconut coir dust extract as a raw material in the production of polyurethane and epoxy resin wood finishes, using benzoylated and methylated derivatives of the extract modified with isocyanates to produce polyurethane resins, or with epichlorohydrin to give epoxy resins, and using the copolymer resins formed in the formulation of wood finishes. Finds that the incorporation of cashew nut shell liquid into the copolymer resins further enhances the film‐forming properties of the finishes.

Condensation products of orange mesocarp extract (flavonoid‐glycosides) and formaldehyde were modified with phenol, cashewnut shell liquid and resorcinol respectively. The copolymer resins formed were used in the formulation of wood adhesives. The glued veneers were evaluated for their shear strength and percentage wood failure assessed. The results showed that the adhesives cured to give gluelines of considerable strength and durability.

Peanut skin tannin extract‐formaldehyde condensates were modified with resorcinol and cashew nut shell liquid. The copolymer resins formed were used as thermosetting and cold‐setting exterior grade wood adhesives for Sapele veneer panels. Results obtained showed that, on addition of paraformaldehyde, the resins modified with resorcinol cured at ambient temperatures while those modified with cashew nut shell liquid cured at higher temperatures. The bonded panels developed strength and durability satisfying the requirements of International Standard Specification for phenolic resin adhesives.

Cashew nut shell liquid (CNSL) and resorcinol modified peanut skin extract adhesive resins were prepared. These resins were subsequently used to produce glues for sapele veneer panels. The bond properties of the plywood were evaluated and results show that the glues formulated using resorcinol modified extracts performed better than those modified with cashew nut shell liquid (CNSL). This was attributed to the high reactivity of resorcinol as compared to the cashew nut shell liquid as shown by the gel times of the various resins.

This paper aims to investigate the corrosion inhibition efficiency of Landolphia heudelotii (LH) on mild steel in 1 M HCl and 0.5 M H₂SO₄ using weight loss and potentiodynamic polarization techniques.

Water extract of LH was used as corrosion inhibitor on mild steel in acidic media at room temperature and elevated temperatures (30-60°C). Various concentrations of the plant extract were prepared from the stock solution obtained after solvent extraction. The inhibition efficiency of LH extract was evaluated and mechanism of adsorption was deduced.

LH extract showed significant corrosion inhibition on mild steel in both acidic media, with inhibition efficiency increasing with extract concentration. Potentiodynamic polarization measurements revealed mixed inhibition mechanism. Optimum inhibition efficiency was recorded at 2500 mg/L after 288 h. Mechanism of adsorption was mainly of physisorption. The inhibitor exhibited good inhibition efficiency even at elevated temperature.

This study provides new data on the anticorrosion characteristics of LH extract under the specified conditions. Further studies could expand the experimental variables and use advanced surface probe techniques.

The developed inhibitor provides an alternative method of inhibiting corrosion on mild steel using eco-friendly materials from natural products which are less toxic, safer, cost-effective and readily available.

The method used was effective and the inhibitor developed can be incorporated in surface coatings where mild steel is used as construction materials, as tube sheets, rods and bars.

This study aims to synthesize pigment and resin from agro-wastes and use them in the formulation of eco-friendly surface coatings.

The pigments and resin were synthesized through a chemical modification of agro-wastes. The pigments were characterized by infrared spectroscopy (FTIR) and were screened for their antimicrobial activities. The physicochemical characteristics of the cashew nutshell liquid (CNSL)-modified resin were evaluated. These precursors and other natural additives were used to formulate surface coatings, and their drying and adhesive properties were evaluated using international testing methods.

It was observed that the curing of the CNSL-modified resin depended on time and temperature. The pigments exhibited antimicrobial activity against E. coli and S. aureus and had high melting points, affirming their stability. The chemically modified precursors successfully yielded surface coatings with acceptable drying times and adhesion to the base substrate.

The use of agro-wastes as the main components of the surface coatings implies waste valorization, a reduction in production costs and the creation of job opportunities for sustainable development. To increase the chemical, physical, corrosion resistance and antimicrobial qualities of paint compositions, chemically modified peanut skin extracts and CNSL can be used as pigments and resins, respectively. This could be a green approach to achieving the targets of Sustainable development goals 11 and 12.

The paper outlines a prospective approach to use unwanted waste (peanut skin, cashew nutshells) and other natural additives as industrial raw materials. These novel surface coating precursors are cost-effective, readily available, eco-friendly and could replace conventional precursors.

The purpose of this paper is to compare the content of nutrients and minerals in various cultivars of Cucurbita maxima.

This is preliminary study, so eight samples from each cultivar of pumpkin used in this study were obtained from local farms from Poland. The following pumpkin cultivars were used: Australian butter, Flat white boer, Garbo, Golden delicious, Golden nugget, Hokkaido, Solor and Zapallito de tronco. In pumpkins elements, dry matter, ash and crude protein were determined. All elements were determined using Inductively Coupled Plasma Optical Emission Spectrometer. Content of dry matter, ash and crude protein according to AOAC methods.

The fruit of Cucurbita maxima, irrespective of cultivar, is a good means of supplementing the diet with highly beneficial fibre, and minerals such as potassium, calcium, phosphorus, magnesium, sulphur, silicon, iron and zinc. The pumpkins richest in minerals are those of the Australian butter cultivar (calcium, manganese, iron), Flat white boer (sodium, silicon, chromium, nickel), Hokkaido (potassium, phosphorus, zinc, chromium) and Solor (magnesium, sulphur, copper), while the Garbo, Golden Delicious and Zapallito de tronco cultivars had the lowest concentrations of minerals.

The results obtained indicate that depending on the consumer’s expectations, pumpkins of various cultivars can be a dietary component that corrects deficiencies in the diet. Pumpkins grown in Poland have been characterised in terms of the content of mineral elements. These vegetables have become an important component of local food in Poland.

The purpose of this paper is to highlight the one bath dyeing method for polyester/wool (PES/Wo) blend fabric with two different semi-synthetic azo dyes developed by chemically modifying the outer skin of Allium cepa.

Chemical modification is the most heartening way to impart improved properties to natural sources. Two different primary amines were coupled with the Allium cepa skin extract by a diazo coupling reaction. Synthesised dyes were characterized for their percentage yield, solubility tests, melting point, particle size analysis as well as FTIR spectroscopy and UV-Visible analysis. One bath dyeing methodology was used for application of synthesized dyes on PES/Wo blend fabric. Dyeing was performed at boil without any additional auxiliary and further percentage dye exhaustion was evaluated.

Dyeing yielded solid shade on PES/Wo blend fabric with satisfactory levelness in dyeing. The efficacy of synthesized dyes for dyeing of PES/Wo fabric was studied by wash, rub, light and sublimation fastness properties, which are in good agreement with commercial requirements. The antimicrobial activity of the synthesized dyes shows excellent activity in dye powder form (AATCC 147 test method) as well as on dyed fabrics (AATCC 100 test method).

Present research work is a first successful attempt to dye PES/Wo blend fabric with semi-synthetic azo dyes in single bath at boil. Such approach facilitates minimum consumption of energy, cost and time.

This paper aims to focus on the optimisation of dyeing recipe for dyeing of silk fabric with semisynthetic azo dyes synthesised by chemical modification of areca nut extract.

The response surface model (Box–Behnken design) was used to establish the relation between the parameters of dyeing such as time, temperature and material to liquor ratio. Their output responses in terms of colour strength (K/S values) are reported. Their relationship was tested for predictability and the experimental values and found to match closely, which confirms the model suitability.

Dyed fabrics were tested for their fastness properties such as wash, rub and lightfastness. The results of the fastness tests indicate that modified dyes have good dyeability towards silk fabric. The dyed fabrics were also tested for ultraviolet protection factor and antimicrobial activity, which showed very promising results.

Banned amine testing was done, which confirms the absence of banned amine in synthesised dyes, which indicates the potential of its sustainability. Also, such an approach of modification of natural dyes as semi-synthetic dyes can be surely considered to be a step towards its widespread acceptability and further commercialisation.