Altered rheokinetic and mechanical behavior of anhydride cured epoxy resin due to addition of cellulose nano-crystals

Abstract

In this work, the effect of cellulose nanocrystals (CNC) addition on the rheo-kinetic behavior and mechanical strength of the anhydride cured epoxy system is studied. The study is conducted under non-isothermal conditions at five different heating ramp rates, namely 1, 2, 5, 8, and 10℃/min. The effect of CNC concentration on the activation energy is also analyzed. The maximum activation energy is observed for 0.5% CNC modified resin with a value of 112.4 kJ/mol for 0.8 degree of conversion. Furthermore, the non-isothermal Arrhenius method is used to predict the rheo-kinetic model that correlates the degree of cure and complex viscosity of the CNC modified resin system. The predicted viscosity model agrees with the experimental data to a great extent with Absolute Average Relative Deviation values in the range of 0.78-0.998. Additionally, the flexural strength of nano-composites is evaluated and found to be increased from 23.6 MPa to 38.2 MPa for neat resin and 2% CNC modified resin sample, respectively. The developed rheo-kinetic modeling will be helpful for efficient and high strength nano-composite product formulation.

Keywords

• Cellulose nano-crystals
• Rheo-kinetic modeling
• Cure kinetics
• Activation Energy
• Anhydride cured epoxy
• Flexural Strength