Epoxy monomers obtained from castor oil using a toxicity-free catalytic system

Development of completely bio‐based epoxy networks derived from epoxidized linseed and castor oil cured with citric acid

“…Compared with the spectrum of CO, an increase in intensity of OH stretch at 3445 cm −1 is found in ECO, which may be because of excess hydroxyl groups formed due to ring opening of some epoxy group. Similar findings have been reported earlier by Hernandez et al…”

“…Similar spectrum and explanation has been reported for synthesized ELO by using 25% amberlite catalyst by Kim et al and using 20% lipase catalyst by Mahendran et al In 1 H‐NMR spectra of ECO (Figure B), epoxide group formed in ricinoleic acid revealed their signals between 2.9 and 3.1 ppm (e) corresponding to the protons to the epoxide group (─CH─). The formation of epoxide ring shifts the signal corresponding to the hydroxyl (─OH) group from 3.6 to 3.85 ppm (d) …”

“…Consequently, there has been a growing interest by researchers from academia as well as industry for adhesive, coating, and composite applications to use epoxidized LO (ELO), acrylated ELO, and epoxidized methyl esters of LO . Similarly, castor oil (CO) is a natural polyol consisting of unsaturated fatty acid, hydroxyl functionalities, usually ricinoleic acid (12‐hydroxy‐9‐ cis ‐octadecenoic acid), which almost covers 90% of the fatty acid content . Such multiple functional sites make it a higher reactive versatile material compared with other plant oils.…”

“…Most importantly, CO is abundantly available and relatively inexpensive nonedible oil to serve as a versatile renewable raw material for future generation biopolymers. Due to abundant availability and its inexpensive nature, epoxidized CO (ECO) is being widely used by researchers worldwide as a bio‐based plasticizer to modify the polymer matrix and also as a raw material to synthesize polyurethane for adhesive and coating applications …”

Screening of ion exchange resin catalysts for epoxidation of oleic acid under the influence of conventional and microwave heating

“…The perhydrolysis step (I) is relatively slow and it takes place spontaneously, but it is enhanced by acid catalysts. In general, the epoxidation of vegetable oils using the Prilezhaev method requires several hours to obtain high conversions . To enhance the perhydrolysis rate, various catalysts can be used, such as enzymes, metals, metal oxides, sulfuric acid and acidic ion exchange resins (AIERs) .…”