Curing Kinetics of Biobased Epoxies for Tailored Applications

Abstract

The curing kinetics of a family of biobased epoxies derived from n-alkyl diphenolate esters differing in ester side chain length were compared with diglycidyl ether of bisphenol A (DGEBA). Isothermal isoconversional analysis and Kamal−Sourour model fitting by differential scanning calorimetry (DSC) were utilized to obtain reaction constants. The biobased epoxides and DGEBA have reaction orders that are comparable while the autocatalytic rate constant of DGEBA was larger than those of the biobased epoxies. As the n-alkyl side chain length of diphenolate esters increased, the autocatalytic rate constant decreased. Furthermore, the non-autocatalytic rate constant for DGEBA is smaller than that of the biobased epoxies. The cause for the difference in rate constants is discussed, and applications are assigned to the epoxies based on curing kinetics.

Divanillin-Based Epoxy Precursors as DGEBA Substitutes for Biobased Epoxy Thermosets

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Fluorine‐Free Superhydrophobic Coatings: Rapid Fabrication and Highly Efficient Oil/Water Separation

“…Chemorheology is the study of the flow properties of the reactive polymer system, and it has been widely used to investigate the cure behavior of different polymeric materials. [ 31–34 ] From the practical standpoint, coatings have to flow during their application. In other words, the viscosity of the coating formulation has to be low enough in order to provide a homogenous distribution of the coating on a substrate, what can dramatically impact the final properties of the coated surfaces.…”

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