Assessing novel thermoset materials from Brazil nut oil: Curing, thermal and mechanical properties
Aina Perez-Nakai, Alejandro Lerma-Canto
, Acerina Trejo-Machín, Iván Dominguez-Candela, Jose Miguel Ferri, Vicent Fombuena
, Acerina Trejo-Machín, Iván Dominguez-Candela, Jose Miguel Ferri, Vicent FombuenaVol. 17., No.12., Pages 1224-1238, 2023
DOI: 10.3144/expresspolymlett.2023.93
DOI: 10.3144/expresspolymlett.2023.93
Corresponding author: Jose Miguel Ferri 
GRAPHICAL ABSTRACT
ABSTRACT
The present work describes, for the first time, the chemical modification and characterization of epoxy resins derived from Brazil nut oil (BNO). The development of a bio-based resin has been carried out by chemically modifying BNO, resulting in epoxidized Brazil nut oil (EBNO). Moreover, through a maleinization process, a crosslinker based on maleinized Brazil nut oil (MBNO) has been employed. Analysis using techniques like iodine value (IV) and oxirane oxygen content (Oo) indicate successful chemical modification. FTIR analysis confirms the presence of reactive functional groups in both EBNO and MBNO, which are responsible for resin crosslinking. Mechanical testing of the different bio-resins developed shows that, in the cured resins, flexural strength and modulus decrease with increasing MBNO content, indicating improved flexibility due to the introduction of MBNO as a crosslinker. Thermal analysis using differential scanning calorimetry (DSC) reveals exothermic peaks corresponding to resin curing appearing at progressively lower temperatures. Therefore, this study successfully modifies BNO and demonstrates its effectiveness as a precursor to develop bio-based epoxy resins. The resulting resins exhibit improved ductile and thermal properties, making them suitable for various applications requiring low mechanical stresses.
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