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Article
Publication date: 7 September 2012

S. Jahanshaei, T. Tabarsa and J. Asghari

The purpose of this paper is to describe the development of an eco‐friendly tannin‐phenol formaldehyde resin (PFT) applicable in the wood composite industry.

Abstract

Purpose

The purpose of this paper is to describe the development of an eco‐friendly tannin‐phenol formaldehyde resin (PFT) applicable in the wood composite industry.

Design/methodology/approach

The bark of oak (Quercus castaneifolia) contains a large amount of condensed tannin. Condensed tannin, with a large amount of Catechol groups was considered for reducing the formaldehyde emission level on the adhesive system. Physical characteristics of synthesized PFT resin were evaluated.

Findings

For optimal extraction, three solvents were used in the extraction process. The results showed that a mixture of water‐methanol (1:1 v/v) as extracting solvent is the best solvent and yields about 14 per cent tannin based on dry weight of bark. For producing tannin phenol formaldehyde adhesive, 10 per cent, 20 per cent and 30 per cent (based on PF dry weight) of PF, substituted with natural extracted tannin. For evaluating PFT performance effects of percentage amount of substitution tannin content on the gel time, viscosity, pH, and density of adhesives were evaluated. Based on emission test (JIS A 1460‐2001) formaldehyde emission of PFT 10 per cent, 20 per cent and 30 per cent were 1.13, 1.12 and 0.4 mg/100 g, which is very low compared with tannin‐free PF.

Research limitations/implications

Tannin‐PF adhesive compared to PF adhesive had lower PH, higher viscosity and shorter gel time.

Practical implications

The method developed provides a simple and excellent renewable resource “tannin” which can be used or partially substituted in phenol formaldehyde adhesive.

Originality/value

Results showed that replacing PF for tannin reduces modulus of rupture (MOR) and modulus of elasticity (MOE) slightly but has significant effects on IB, water absorption and thickness swelling.

Details

Pigment & Resin Technology, vol. 41 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 6 March 2017

Santiago Flores Merino, Juan José Caprari, Luis Vasquez Torres, Luis Figueroa Ramos and Antonella Hadzich Girola

The purpose of this paper is to study the ability of commercial tara powder to convert rust into iron tannate and evaluate their use as raw material for the formulation of water…

Abstract

Purpose

The purpose of this paper is to study the ability of commercial tara powder to convert rust into iron tannate and evaluate their use as raw material for the formulation of water based rust converter.

Design/methodology/approach

Water-borne acrylic primers were formulated with tara powder and aqueous tara extract and applied on steel rusted by three different methods. The conversion of rusted steel by tara tannins was studied by X-ray diffraction spectroscopy, infrared spectroscopy and scanning electron microscopy. The acrylic primers, containing hydrolysable tannins, were coated with alkyd finish and were evaluated in comparison to commercial systems in accelerated corrosion tests. The corrosion inhibition effects of tara powder on mild steel in 0.1M NaCl were studied by DC electrochemical techniques.

Findings

Tara tannin converts rust to ferric tannate and increases the magnetite content of rusted steel. The water-based acrylic primer formulated with aqueous extract of tara, alkyd-coated finish, showed performance equivalent to pure alkyd system.

Research limitations/implications

The chlorides content in the commercial tara powder can be screened the beneficial effect of hydrolysable tannins to convert rust. Furthermore, the water-based rust converter formulated with acrylic resin may be sensitive to salt contamination of rust.

Originality/value

Hydrolysable tannins from commercial tara powder have not been studied yet in its application to the development of rust converters. A water-based primer formulated with commercial tara powder developed for the effective treatment of rusted surfaces can be of interest as an environmentally friendly to current commercial approaches.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 28 March 2024

Mozhgan Hosseinnezhad, Kamaladin Gharanjig, Shahid Adeel and Alireza Mahmoudi Nahavandi

Agricultural waste and food sources are some of the pollutants of the environment. One of these wastes is the peel of fruits that cannot be consumed as food. In this regard…

Abstract

Purpose

Agricultural waste and food sources are some of the pollutants of the environment. One of these wastes is the peel of fruits that cannot be consumed as food. In this regard, walnut husk (WH) and oleaster peel (PO) are known as two important sources of tannin and are bulky wastes. Because of the high percentage of tannin, these materials can be used as a natural source for the preparation of bio-mordant in the dyeing process.

Design/methodology/approach

In this study, Reseda and Madder were used as natural dyes in the presence of a mixture of two bio-mordants. WH and PO were selected as bio-mordant. All natural resources are extracted to obtain the juice. The phenolic percentage of tannin-containing extracts was evaluated and then it was used for wool yarns by premordanting method. The results of evaluating the fastness properties using the ISO method.

Findings

The most important achievement of this research is the use of agricultural waste in the dyeing process to reduce environmental pollution and create added value. All compounds rich in tannin have some phenolic components, therefore the amount of phenolic content of these extracts was evaluated. The effect of mixing the mordant on the color characteristics of the yarns was investigated and the results showed that changing the ratio of the combination of two mordant is effective on the K/S values. The results of evaluating the fastness properties using the ISO method showed that the washing, rubbing and light fastness in the presence of mordant is good, good and moderate, respectively.

Originality/value

In this paper, to the best of the authors’ knowledge, for the first time, the combination of two natural extracts obtained from agricultural waste has been used to create a new bio-mordant on fibers and improve stability.

Details

Research Journal of Textile and Apparel, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 7 November 2016

Pawin Wongkhamprai and Manthana Jariyaboon

The aim of this work was to investigate how Andrographis paniculata (Burm.f.) Wall.ex Nees extract affected the corrosion of low-carbon (C) steel in 0.1M HCl.

Abstract

Purpose

The aim of this work was to investigate how Andrographis paniculata (Burm.f.) Wall.ex Nees extract affected the corrosion of low-carbon (C) steel in 0.1M HCl.

Design/methodology/approach

The Andrographis paniculata (Burm.f.) Wall.ex Nees was extracted into distilled water at 70°C for 1 h. The corrosion inhibition efficiency of the extract was determined in 0.1M HCl using weight loss measurements, potentiodynamic polarization and electrochemical impedance spectroscopy. The effects of extract concentrations and of temperature were investigated.

Findings

The Andrographis paniculata (Burm.f.) Wall.ex Nees extract could inhibit the corrosion process of low-C steel in 0.1M HCl. With the extract concentration of 1 g/l, an inhibition efficiency of 96.3 per cent was obtained. The extract acted as an anodic inhibitor. The adsorption process of the extract was physisorption and it followed the Langmuir adsorption isotherm.

Originality/value

This paper revealed that Andrographis paniculata (Burm.f.) Wall.ex Nees cultivated in Thailand, which was extracted using a simple and environmentally friendly method, could act as a very good green corrosion inhibitor for low-C steel in 0.1M HCl solution.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 March 1910

MR. ALLAN BARNS‐GRAHAM, of Craigallian, Milngavie, has sent us a copy of a letter, addressed by him to the Secretary of the Scottish Agricultural Organisation Society and printed…

Abstract

MR. ALLAN BARNS‐GRAHAM, of Craigallian, Milngavie, has sent us a copy of a letter, addressed by him to the Secretary of the Scottish Agricultural Organisation Society and printed in pamphlet form, which contains a number of points of considerable importance. MR. BARNS‐GRAHAM observes that Bran and “Thirds” play a most important part in the rearing and feeding of cattle, pigs, and poultry, and in the production of milk; that these two products ought to be used to a much greater extent than they are now; that large quantities are annually exported from this country; and that the supplies ought to be jealously guarded. He expresses the hope that the Agricultural Organisation Societies of Great Britain and Ireland will in no way encourage the manufacture of condensed milk—on the ground that it is not in the interest of the public health, nor in the interest of agriculture to encourage the manufacture of any article of food which can be made to keep indefinitely by artificial means. This appears to us to be a somewhat strange position to take up, unless the author's intention is to condemn the practice of keeping food products by means of chemical preservatives—in which case we agree with him. But the proper preservation of many food products by legitimate and harmless methods, not involving the use of chemicals or of other objectionable devices, is surely permissible and valuable to the community. Properly prepared and sterilised condensed milk is a very useful commodity if it is what it purports to be. In this connection we may say, however, that condensed milk containing large quantities of added sugar ought not to be sold as “condensed milk,” but as “condensed sweetened milk,” or “condensed milk and sugar”—the proportion of added sugar being prominently disclosed; while, in our view, the sale of “condensed sweetened; ‘separated,’ or ‘machine‐skimmed’ milk” ought to be prohibited altogether.

Details

British Food Journal, vol. 12 no. 3
Type: Research Article
ISSN: 0007-070X

Article
Publication date: 17 May 2022

Sampson Kofi Kyei, William Iheanyi Eke, Godfred Darko and Onyewuchi Akaranta

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

Abstract

Purpose

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

Design/methodology/approach

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.

Findings

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.

Practical implications

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.

Originality/value

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.

Details

Pigment & Resin Technology, vol. 52 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 22 March 2011

A.M. Shah, A.A. Rahim, S. Yahya, P.B. Raja and S.A. Hamid

The purpose of this paper is to evaluate the corrosion inhibition potential of mangrove (Rhizopora apiculata) tannin in hydrochloric acid medium on copper with the view of…

Abstract

Purpose

The purpose of this paper is to evaluate the corrosion inhibition potential of mangrove (Rhizopora apiculata) tannin in hydrochloric acid medium on copper with the view of developing a natural corrosion inhibitor.

Design/methodology/approach

The mangrove tannin was extracted from the mangrove bark and its anticorrosion potential was studied by weight loss, electrochemical and scanning electron microscopy (SEM) analysis.

Findings

It has been found that the mangrove tannin effectively inhibits the corrosion on copper metal in hydrochloric acid solution. The results of the electrochemical and weight loss methods showed that the inhibition efficiency of mangrove tannin increases with increasing its concentration. Inhibition is achieved through the adsorption of tannin molecules onto the copper surface and the adsorption follows the Langmuir adsorption isotherm model. SEM study also supports the adsorption of the inhibitor molecules onto the copper surface.

Originality/value

In this paper, mangrove tannin has been studied for the first time as a potential copper corrosion inhibitor in hydrochloric acid medium. The anticorrosion effect of tannin has been proven by standard methods. This natural inhibitor could find use in industries where copper is used as a fabrication metal.

Details

Pigment & Resin Technology, vol. 40 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 May 1996

O. Akaranta

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…

Abstract

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.

Details

Pigment & Resin Technology, vol. 25 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 December 1999

O. Akaranta and A.O. Aloko

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…

402

Abstract

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.

Details

Pigment & Resin Technology, vol. 28 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 October 1999

O. Akaranta and D. Wankasi

Peanut skin tannin extract‐formaldehyde condensates were modified with resorcinol and cashew nut shell liquid. The copolymer resins formed were used as thermosetting and…

Abstract

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.

Details

Pigment & Resin Technology, vol. 28 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

1 – 10 of 378