Phenalkamine curing agents for epoxy resin: characterization and structure property relationship

2018 ◽  
Vol 47 (4) ◽  
pp. 281-289 ◽  
Author(s):  
Kunal Wazarkar ◽  
Anagha S. Sabnis
Keyword(s):  
Epoxy Resin ◽  
Electrochemical Impedance ◽  
Salt Spray ◽  
Structure Property ◽  
Cashew Nut Shell Liquid ◽  
Performance Properties ◽  
Content Type ◽  
Cashew Nut ◽  
Curing Agents ◽  
Cashew Nut Shell

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.

scholarly journals Bio-based epoxy resin toughening with cashew nut shell liquid-derived resin

2015 ◽  
Vol 3 (3) ◽  
pp. 80-92 ◽  
Author(s):  
Anthony Maiorana ◽  
Liyun Ren ◽  
Giada Lo Re ◽  
Stephen Spinella ◽  
Chang Y. Ryu ◽  
...  
Keyword(s):  
Epoxy Resin ◽  
Cashew Nut Shell Liquid ◽  
Cashew Nut ◽  
Cashew Nut Shell

Biobased epoxy resin toughening with cashew nut shell liquid-derived resin

2015 ◽  
Vol 3 (July–September) ◽  
pp. 1-38
Author(s):  
Anthony Maiorana ◽  
Giada Lo Re ◽  
Liyun Ren ◽  
Chang Y. Ryu ◽  
Stephen Spinella ◽  
...  
Keyword(s):  
Epoxy Resin ◽  
Cashew Nut Shell Liquid ◽  
Cashew Nut ◽  
Cashew Nut Shell

Novel Cycloaliphatic Cashew Nut Shell Liquid Derivatives and their use as Isocyanate Protective Groups

2021 ◽  
Vol 7 (4) ◽  
Author(s):  
Pietro Campaner
Keyword(s):  
Chemical Structure ◽  
Hydrolytic Stability ◽  
Cashew Nut Shell Liquid ◽  
Cashew Nut ◽  
Lower Viscosity ◽  
Epoxy Curing ◽  
Protective Groups ◽  
Natural Oil ◽  
Curing Agents ◽  
Cashew Nut Shell

Cardanol (3-pentadecenyl-phenol), a well-known non-edible natural oil obtained as a by-product of the Cashew Industry, represents a valid alternative to petro-based derivatives, thanks to its peculiar chemical structure. When selected as polymer building block in the synthesis of epoxy curing agents or polyols and diols for polyurethane applications, cardanol can impart unique benefits, like chemical resistance, hydrolytic stability, thermal resistance and balanced mechanical properties. Once used in polyurethane prepolymers, it demonstrates various benefits, including favorable and easily tunable deblocking conditions, lower viscosity of resulting NCO-blocked prepolymers and excellent storage stability in comparison to commonly used phenolic compounds (phenol, nonylphenol, in particular). In this paper, novel cardanol-based fully cycloaliphatic derivatives (e.g. cyclohexanol, oxime, lactam-types) will be presented, investigating their use as innovative isocyanate protective groups with faster reactivity and lower deblocking temperatures than petro-derived benchmarks.

Curing kinetic, thermal and adhesive properties of epoxy resin cured with cashew nut shell liquid

2015 ◽  
Vol 600 ◽  
pp. 20-27 ◽  
Author(s):  
Pornnpa Kasemsiri ◽  
Arthit Neramittagapong ◽  
Prinya Chindaprasirt
Keyword(s):  
Epoxy Resin ◽  
Cashew Nut Shell Liquid ◽  
Adhesive Properties ◽  
Cashew Nut ◽  
Curing Kinetic ◽  
Cashew Nut Shell

scholarly journals Self-Healing Ability of Epoxy Vitrimer Nanocomposites Containing Bio-Based Curing Agents and Carbon Nanotubes for Corrosion Protection

2021 ◽  
Author(s):  
Narubeth Lorwanishpaisarn ◽  
Natwat Srik ◽  
Kaewta Jetsrisuparb ◽  
Jesper T.N. Knijnenburg ◽  
Somnuk Theerakulpisut ◽  
...  
Keyword(s):  
Near Infrared ◽  
Thermomechanical Properties ◽  
Self Healing ◽  
Coated Steel ◽  
Cashew Nut Shell Liquid ◽  
Corrosion Properties ◽  
Cashew Nut ◽  
Healing Efficiency ◽  
Curing Agents ◽  
Cashew Nut Shell

Abstract Epoxy is extensively used for anti-corrosion coatings on metallic materials. Conventional epoxy coatings have a permanent crosslink network that is unable to repair itself when cracks and damages occur on the coating layer. This study aims to develop self-healing epoxy vitrimer/carbon nanotube (CNTs) nanocomposite for coating. Two bio-based curing agents viz., cashew nut shell liquid (CNSL) and citric acid (CA) were employed to create covalent adaptable networks. The 0-0.5 wt% CNTs were also incorporated into epoxy/CNSL/CA matrix (V-CNT0-0.5). Based on the results of our study, thermomechanical properties of V-CNT nanocomposites increased with increasing CNTs content. The bond exchange reaction of esterification was thermally activated by near infrared (NIR) light. The V-CNT0.5 showed the highest self-healing efficiency in Shore D hardness of 97.37%. The corrosion resistance of coated steel with V-CNT0 and V-CNT0.5 were observed after immersing the samples in 3.5 wt% NaCl for 7 days. The corrosion rate of coated steel with V-CNT0.5 decreased from 9.53 x 102 MPY to 3.12 x 10-5 MPY whereas an increase in protection efficiency of 99.99% was observed. By taking advantages of the superior self-healing and anti-corrosion properties, V-CNT0.5 could prove to be a desirable organic anti-corrosion coating material.

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