Work

Cure Kinetics and Chemorheological Modeling of a Transesterification‐Based Epoxy/Anhydride Vitrimer

Year: 2025

Type: article

Abstract: ABSTRACT This study presents the cure kinetics, glass transition temperature ( T g ) and chemoviscosity models for an epoxy vitrimer synthesized from DGEBA, methylhexahydrophthalic anhydride (MHHPA), and triethanolamine (TEOA). Cure and T g data were obtained by differential scanning calorimetry, while chemoviscosity was studied by isothermal flow rheometry. An autocatalytic model simulates the cure behavior with an average reaction rate error of 8% and a degree of cure error of 9%. T g evolves from −12°C in the uncured state to an ultimate value of 101°C, following the DiBenedetto relationship with a convexity factor (λ) of 0.59. Chemoviscosity modeling focuses on the early cure regime, with a model based on the kinetics of viscosity at a reference temperature and an inverse temperature exponential dependence showing good agreement with experimental data, achieving an average relative error of 12%. The stress relaxation time decreases from 14.6 h at 190°C to 2 h at 220°C, with a topology freezing temperature of 172°C and a dynamic bond exchange activation energy of 125 kJ/mol determined through stress relaxation experiments. This study delivers the first set of comprehensive processing models for an epoxy anhydride vitrimer, providing a framework for optimal coating manufacture and extending vitrimer application into corrosion‐resistant surface technologies.

Source: Journal of Applied Polymer Science

DOI: 10.1002/app.70027

Authors: Romeo E. Ekperi, Festus I. Anagwu, Alexandros A. Skordos

Institution: Cranfield University

Language: English

Topic: Epoxy Resin Curing Processes

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,140

Funder: Australian Government