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

Abstract

IntroductionEpoxy resins are building blocks used to form a versatile class of thermoset polymers. They can be cured under a wide range of conditions and exist as solids or liquids at room temperature. Liquid epoxy resins are ideal for manufacturing large one-piece structural composites such as wind turbine blades and car frames.1 Higherviscosity liquid epoxy resins also find uses as structural adhesives for wind turbine blades, car frames and electronics. Aside from composites, liquid and solid epoxy resins also find a wide variety of uses as protective coatings due to their anticorrosive nature and good adhesion to metal substrates.2 Epoxy resins can be designed such that after curing they result in thermosets with high modulus and glass transition temperatures. However, these thermosets may possess low impact resistance and brittle fracture. Bisphenol A (BPA) and, subsequently, the diglycidyl ether of bisphenol A (DGEBA), is currently used for the preparation of a versatile family of high-performance cured epoxy resins.

Structure–property relationships of a bio‐based reactive diluent in a bio‐based epoxy resin

“…Therefore, analysis of this data is limited to determining trends as opposed to quantitative changes in M x . Some of us have utilized this method to characterize M x in previous work …”

“…However, bio‐based epoxy resins are often crystalline solids . Some notable liquid systems that have been recently reported are based on furfural derivatives, terpenes, gallic acid, and cardanol derivatives …”

Review on Adhesives and Surface Treatments for Structural Applications: Recent Developments on Sustainability and Implementation for Metal and Composite Substrates

“…In their own preliminary work, bio-based monomers of n-alkyl esters of diphenolic acid (DGEDP epoxides) with comparable thermal and mechanical properties to classical DGEBA epoxides [ 29 , 30 ], were developed. These were copolymerized with a derivative of cashew nutshell oil [ 31 ]. Nanocrystalline cellulose served as rheological auxiliary and bio-based bis (furfurylamine) as a cross-linking agent.…”

Sustainable Alternative Composites Using Waste Vegetable Oil Based Resins

“…Increasing environmental concerns, tighter legislation and awareness about the toxicity of these resins have driven stakeholders to seek more sustainable alternatives for the thermoset composite market [15,16]. In this regard, the community has explored the production of thermoset matrices from environmentally-friendly resins as a strategy to reduce the manufacturing impacts [17][18][19]. Amongst different candidates, vegetable oils (VOs) have been considered as a key platform to enable a shift towards a greener polymer industry due features such as price, availability, safety and chemical versatility [20].…”