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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.

This study aims to discuss the impact of using bio-polymer (kraft lignin) in the formulation of passenger vehicle disc brake pads (as a substitute for cashew nutshell liquid [CNSL]-based friction dust) and investigate the characteristics of the pads.

Within the scope of this investigation, three different brake pads were generated by altering the biopolymer-lignin content in conjunction with the friction dust from CNSL without modifying the other components. The brake pads were created in accordance with industry-standard practices. Industrial standards were used to evaluate the newly created brake pad’s thermal, physical and mechanical qualities. The tribological properties of the materials were determined using a full-scale inertia brake dynamometer. The scanning electron microscope examined the worn surfaces in conjunction with elemental mapping.

The test findings suggest that the brake pads filled with biopolymer-lignin and CNSL-based friction dust (as a partial replacement 50%) exhibited excellent thermal, physical, mechanical characteristics, as well as steady friction and low wear rate.

A bio-polymer (kraft lignin) in friction composites has the potential to produce eco-friendly brake pads and improve the tribological performance of its copper free-composition, which might be used to replace CNSL-based friction dust in friction composites by addressing the issues raised in this work.

The liquid extract obtained from the natural cashew nutshell is rich in phenolic substances which are derived from anacardic acid C6H3(OH) (CO2H) (C15H31‐n), where n may have values of 0, 2, 4 or 6 and represents various degrees of unsaturation in the aliphatic C15 side‐chain. Industrial decarboxylation of this material affords cardanol C6H4(OH) (C15H31‐n) plus other substituted phenols and polymeric residues. Tyman et al. (197, 198) have studied the analysis of all these products using GC, molecular distillation, TLC and mass spectrometry. After hydrogenation and the formation of the corresponding methyl esters, the products were analysed by GC using glass columns (5ft × 3/16in) packed with acid washed and silanized Diatomite as support material and which was coated with non‐polar stationary phases such as SE30, SE25 or APL, or semi‐polar phases such as 0V17, Dexil 300 or PEGA. Alternatively, the samples were subjected to an acetylation procedure prior to GC examination on columns containing Dexil 300, SE30 or SE52. The GC equipment consisted of a Pye‐Unicam model 104 instrument operated with nitrogen carrier gas (flow rate 45cm3 min−1) and equipped with FID.

The first part of this article, published last month, was primarily concerned with a general approach to the problem and dealt with some of the materials used for corrosion resistant floors, including impervious membranes, PVC and polythene. This month, in concluding the article, the author gives details of several types of floor and their suitability in different industries.

The purpose of this study is to synthesize structurally different phenalkamines based on cardanol, a renewable material obtained from cashew nut shell liquid, and to evaluate their effect on performance properties of the coatings.

For this purpose, the Mannich reaction between cardanol, formaldehyde and various diamines such as diaminodiphenyl methane (DDM), hexamethylene diamine, Jeffamine D400 and Jeffamine T403 were carried out to produce novel phenalkamines. Resultant phenalkamines were used as curing agents for commercial DGEBPA epoxy resin and were evaluated for performance properties.

The mechanical, optical, chemical, thermal and anticorrosive properties were evaluated and compared with those of commercial phenalkamine AG141. It was observed that anticorrosive properties evaluated using a salt spray test and electrochemical impedance spectroscopy revealed significant improvement in anticorrosive performance of coatings cured with synthesized phenalkamines based on DDM and T403 as compared to the coatings based on commercial phenalkamine AG141.

To obtain optimum performance properties of the coatings, a combination of phenalkamines can be used.

Curing time and gel times of all the phenalkamines can be further studied under wet and humid conditions. In addition, the variation in coating properties under humid conditions can be investigated.

In this study, newer phenalkamines were synthesized and used as curing agents for epoxy coatings. So far, there have been no reports indicating the synthesis and application of phenalkamines based on polyetheramines, namely, Jeffamine D400 and Jeffamine T403, in coating applications.

The aim of the this study is to develop a new class of composites which would be more commercially viable and environmentally sustainable via reduced resource depletion, as there has been global interest in utilization of natural resources. The dry sliding wear behavior of glass-epoxy (G-E)-based composites filled with tamarind kernel powder (TKP) in different volume fractions of fillers (0 per cent, 3 per cent and 6 per cent) was studied as per standards.

In the present study, the analysis and optimization of the wear process has been studied. The Taguchi approach to experimental design was used to identify the effect of wear parameters such as applied load, sliding velocity and sliding distance. Taguchi tools such as analysis of variance and multiple linear regression models have been used to analyze, obtain the significant parameters and evaluate the optimum combination levels of wear process parameters. The results of Taguchi analysis indicate that sliding distance was found to be the prominent parameter affecting wear volume loss compared to other wear parameters.

The G-E composites with 3 and 6 vol.% of TKP had the lowest wear volume loss. Multiple linear regression models for all the tested composites’ results well match with experimental results. Confirmation tests were conducted to validate the analysis. There was a close relationship between the experimental results and the statistical model.

However, to the best of author’s knowledge, these literature reports related to natural organic filler materials are limited to analysis of polymer matrix composite. Further, the addition of TKP particle as a potential filler has not been addressed. An attempt has been made to clarify the technical viability of TKP as a potential filler for G-E composite.

The purpose of this paper is to investigate the physical and mechanical characteristics of the roasted cashew nut during fracture, by subjecting the nut to varying impact load tests at different orientations to ascertain the critical impact load that fractures the shell without damaging the kernel within. This load value was correlated with other parameters; shell/kernel moisture content level, average nut mass, to determine the required projection velocity to achieve this force. This projection velocity is the critical factor in sizing and design of the optimum configurations of the shelling impeller.

Mechanical properties of roasted cashew nut were first determined to know their fracture points. Each component of the shelling machine was designed. The components were assembled and the machine was tested for performance.

Machine throughput capacity was determined as 15.57 kg/h; shelling efficiency was 95 per cent; and whole kernel recovery was 70 per cent.

The efficiency in terms of whole kernel recovery could be improved by improving the pretreatment measures on the nuts.

The paper presents a machine which is affordable to peasant farmers and requires little or no training for operation and maintenance. The advantage of reduced unit cost can be derived from large‐scale commercial production of this sheller.

The purpose of this study is to investigate the heat resistance and heat-resistant oxygen aging of 4-nitrophthalonitrile-etherified cardanol-phenol-formaldehyde (PPCF) to further use and develop the resin as the matrix resin of high-temperature resistant adhesives and coatings.

PPCF resin was synthesized by 4-nitrophthalonitrile and cardanol-phenol-formaldehyde (PCF). The structures of PPCF and PCF were investigated by Fourier transform infrared, differential scanning calorimetry and proton nuclear magnetic resonance. In addition, the heat resistance and processability of PPCF and PCF resins were studied by dynamic mechanical analysis, thermogravimetric analysis, scanning electronic microscopy (SEM), X-ray diffraction (XRD) techniques and rheological studies.

The results reveal that PPCF forms a cross-linked network at a lower temperature. PPCF resin has excellent resistance under thermal aging in an air atmosphere and that it still had a certain residual weight after aging at 500°C for 2 h, whereas the PCF resin is completely decomposed.

4-Nitrophthalonitrile was introduced into PCF resin, and XRD and SEM were used to investigate the high temperature residual carbon rate and heat-resistant oxygen aging properties of PPCF and PCF resins.

The health-promoting phytochemicals such as phenolic compounds and flavonoids present in nonfatty portion of pecan nut remain overlooked. The present study aimed to evaluate the nutritional and antinutritional/phytochemical constituents of pecan nut and its effect (as a whole nut flour) on the blood lipid profile in the rat model.

The nutritional composition as well as phytochemicals were evaluated by using standard chemical methods. A controlled randomized study was conducted to assess the hypocholesterolemic effect of nut supplementation in male Wistar albino rats.

Phytochemicals/antinutrients analysis exhibited remarkable amount of phenolic compounds (47.05 ± 9.85–302.67 ± 7.72 mg GAE/100 g) and flavonoids (44.95 ± 0.23 mg/100 g) with low trypsin inhibitor activity (TIA) (1.18 ± 0.03 TIU/mg), saponins (0.49 ± 0.04 g/100 g), alkaloids (0.26 ± 0.03 mg/100 g), phytic acid (854.75 ± 15.47) and oxalates (8.15 ± 0.58 mg/100 g) content. Kernel oil showed 2.87 ± 0.75 meq O₂/kg oil peroxide value (PV), well below the maximum permissible limit, demonstrating good oxidative stability of pecan oil. Pecan nut-supplemented diet exhibited a favorable alteration in the blood lipid profile by decreasing total cholesterol (TC) (from 85.42 ± 1.62–229.23 ± 3.43 to 72.24 ± 1.39–106.10 ± 1.69 mg/dl) and low-density lipoprotein cholesterol (LDL-C) (from 64.02 ± 1.96–199.07 ± 4.40 to 38.73 ± 0.79–55.48 ± 1.69 mg/dl) and increasing high density lipoprotein cholesterol (HDL-C) (from 8.70 ± 0.85–9.64 ± 1.10 to 20.25 ± 0.65–24.96 ± 0.56 mg/dl) when compared with control (CC).

This information would be further useful for assessing the biological quality of pecan nut as well as developing value-added food products by exploiting deoiled pecan protein concentrates.

Pecan nut is a rich source of traditional nutrients and phytochemicals and can be recommended to patients with hypercholesterolemia and related cardiovascular diseases.