Curing kinetics, thermal and morphological characterization of the biobased thermosets from epoxy resin/epoxidized hemp oil

- Synthesis of epoxidized hemp oil.
- Epoxy resins/epoxidized hemp oil- curing properties with natural hydroxyl acids.
- TG/FT-IR/MS analysis of epoxy resins/epoxidized hemp oil cured with natural hydroxyl acids.

The paper presents the synthesis and thermal behavior of an epoxy matrix from diglycidyl ether of bisphenol A (DGEBA) and epoxidized hemp oil crosslinked with two hydroxy carboxylic acids (HAc). Epoxidized hemp oil (EHO) was obtained via epoxidation in situ with peroxyacetic acid. The chemical structures of hemp oil (HO), EHO and epoxy matrix were confirmed using FT-IR and 1H NMR spectroscopy. The kinetics of the curing reactions were studied by differential scanning calorimetry (DSC) using multivariate non-linear regression method from the “Thermokinetics-3” software (Netzsch). Also, the thermal decomposition behavior of network has been studied in nitrogen atmosphere up to 600 °C using simultaneous TG/FT-IR/MS technique. Using the above software, the global kinetic parameters of thermal decomposition were determined and was found that the thermal decomposition process occurs in three steps. A good correlation was observed between experimental and simulated data. The chemical composition of gases that arise in the process of thermal decomposition was assessed using FT-IR and MS techniques.