Search results
1 – 5 of 5Anand Dixit, Kunal Wazarkar and Anagha S. Sabnis
Epoxy acrylate which is commercially utilized for UV curable coatings although has excellent adhesion, flexibility, hardness and chemical resistance, they lack in antimicrobial…
Abstract
Purpose
Epoxy acrylate which is commercially utilized for UV curable coatings although has excellent adhesion, flexibility, hardness and chemical resistance, they lack in antimicrobial properties. Citric acid (CA) is economical as well as a bio-based compound which possess an antimicrobial activity. So, the purpose of this research investigation is the preparation of CA-based oligomer which can be further incorporated with epoxy acrylate and tri (propylene glycol) Diacrylate (TPGDA) to form uv curable coating and the study of its antimicrobial property.
Design/methodology/approach
A UV-curable unsaturated oligomer (CUV) was synthesized from CA and glycidyl methacrylate (GMA). The chemical structure of CUV was confirmed by FTIR, 1H NMR, GPC, hydroxyl value, acid value and iodine value. Further, CUV was assimilated as an antimicrobial as well as crosslinking agent to copolymerize with epoxy acrylate oligomer and a series of UV-cured antimicrobial coatings were concocted by employing UV-curing machine. The consequence of varying the fraction of CUV on the mechanical, chemical, thermal and antimicrobial properties of UV-cured wood coatings was explored.
Findings
Results exhibited good mechanical, chemical and thermal properties. In addition, it was perceived that the zone of inhibition against S. aureus got enlarged with increasing content of CUV in the coating formulation.
Originality/value
The synthesized bio-based CUV reveals an extensive potential to ameliorate the antimicrobial properties of UV-curable coatings.
Details
Keywords
Kunal Wazarkar and Anagha S. Sabnis
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
To obtain optimum performance properties of the coatings, a combination of phenalkamines can be used.
Practical implications
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.
Originality/value
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.
Details
Keywords
Nikita Mhadeshwar, Kunal Wazarkar and Anagha S. Sabnis
This paper aims to prepare acrylic functional ricinoleic acid monomer and incorporate it in conventional miniemulsion polymerization. Subsequently, paints were formulated to study…
Abstract
Purpose
This paper aims to prepare acrylic functional ricinoleic acid monomer and incorporate it in conventional miniemulsion polymerization. Subsequently, paints were formulated to study the variation in final coating properties.
Design/methodology/approach
Synthesis process involved the esterification of ricinoleic acid with 2-hydroxy methyl methacrylate in the presence of FASCAT-4100 catalyst. The final product of the reaction, methacrylated ricinoleic acid (MRA), was confirmed using Fourier-transform infrared spectroscopy and 1H-nuclear magnetic resonance spectroscopy and determining acid and iodine value. Further, MRA was incorporated in various concentrations (1, 2 and 3 Wt.%) along with methyl acrylate and butyl acrylate in conventional miniemulsion polymerization and paints were formulated thereof.
Findings
It was observed that with the addition of MRA monomer, flexibility of emulsion films increased as indicated by glass transition temperature and elongation value (percentage). Moreover, with the addition of MRA monomer, improvement in mechanical and chemical properties of the coatings was observed.
Research limitations/implications
Even a low concentration MRA monomer (as low as 3 per cent) caused a significant reduction in the glass transition temperature of emulsion films. Thus, it can be efficiently used in applications such as adhesives and elastomeric coatings.
Originality/value
The acrylic functional monomer derived from ricinoleic acid is unique and not yet incorporated in miniemulsion polymerization. The synthesized monomer can be used in coatings where low Tg emulsions are required.
Details
Keywords
Dawid J. D'Melo, Anagha S. Sabnis, Mohan A. Shenoy and Mukesh S. Kathalewar
The purpose of this paper is to evaluate the efficiency of acrylated guar gum (AGG) as an additive in alkyd resin for improved mechanical properties and to optimize the results of…
Abstract
Purpose
The purpose of this paper is to evaluate the efficiency of acrylated guar gum (AGG) as an additive in alkyd resin for improved mechanical properties and to optimize the results of such an addition.
Design/methodology/approach
For studying the effect of AGG on coating properties, guar gum was modified to various degrees of esterification and various compositions of alkyd systems were made by incorporating different concentrations of AGG. The mechanical and solvent absorption of the unmodified and modified alkyd systems were characterized.
Findings
The incorporation of AGG into alkyd coating showed significant improvement of mechanical properties over the unmodified one. The modification caused an additional crosslink site through its unsaturation which led to increased crosslink density without phase separation of additive from the alkyd system which was confirmed by SEM scans.
Research limitations/implications
The reactive additive, AGG used in the present study was synthesised using acryloyl chloride. Besides, it could also be synthesised from methacryloyl chloride and the effect of methyl substitution on water and solvent absorption could be studied.
Practical implications
The method developed provided a simple and practical solution to improving the mechanical properties of alkyd coatings.
Originality/value
The method for enhancing mechanical properties of cured alkyd system was novel and could find numerous applications in surface coatings.
Details
Keywords
Mukesh Kathalewar, Anagha Sabnis and Gulzar Waghoo
The purpose of this paper is to explore the application of triglycidyl resin (TGC) prepared from cardanol as partial replacement of conventional bis-phenol A (BPA) based epoxy…
Abstract
Purpose
The purpose of this paper is to explore the application of triglycidyl resin (TGC) prepared from cardanol as partial replacement of conventional bis-phenol A (BPA) based epoxy resin for zinc rich primers (ZRPs).
Design/methodology/approach
The synthesis of new platform chemicals that are based on renewable resources has been accepted as a strategy to contribute to sustainable development due to the anticipated depletion of fossil oil reserves and rising oil prices. We prepared a tri-functional epoxy resin from cardanol which can be used as partial replacement of BPA based epoxy. The ZRPs were prepared using 50:50 ratio of TGC:BPA epoxy, and the coatings were evaluated for mechanical, chemical and anticorrosive properties.
Findings
The 50 per cent replacement of BPA based epoxy by TGC resulted in at par mechanical, chemical and anticorrosive properties as evaluated by various methods. The successful implementation can thus contribute to sustainable development by “green chemistry” route.
Research limitations/implications
The prepared TGC resin in the current work was studied for application in ZRPs. This can also be explored for high performance coatings, adhesives and other engineering applications.
Practical implications
The TGC binder was prepared by simple two-step reaction. This can successfully be used as binder for coating application without any modifications.
Originality/value
A novel approach of using green and ecofriendly TGC resin as replacement of high cost BPA based epoxy was explored and can be implemented for numerous applications.
Details