Anisotropic frontal polymerization in a model resin-copper composite

Yuan Gao, Univ Illinois, Beckman Inst Adv Sci & Technol, Urbana, IL 61801 USA; Univ Illinois, Dept Aerosp Engn, Urbana, IL 61801 USA
Sarah Li, Louisiana State Univ, Dept Chem, Baton Rouge, LA 70803 USA; Baton Rouge Magnet High Sch, Baton Rouge, LA 70806 USA
Jin-Young Kim, Univ Illinois, Beckman Inst Adv Sci & Technol, Urbana, IL 61801 USA; Univ Illinois, Dept Aerosp Engn, Urbana, IL 61801 USA
Imogen Hoffman, Louisiana State Univ, Dept Chem, Baton Rouge, LA 70803 USA
Sagar K. Vyas, Univ Illinois, Beckman Inst Adv Sci & Technol, Urbana, IL 61801 USA; Univ Illinois, Dept Aerosp Engn, Urbana, IL 61801 USA
John A. Pojman, Louisiana State Univ, Dept Chem, Baton Rouge, LA 70803 USA
Philippe H. Geubelle, Univ Illinois, Beckman Inst Adv Sci & Technol, Urbana, IL 61801 USA; Univ Illinois, Dept Aerosp Engn, Urbana, IL 61801 USA

Abstract

This work investigates experimentally and numerically frontal polymerization in a thermally anisotropic system with parallel copper strips embedded in 1,6-hexanediol diacrylate resin. Both experiments and multiphysics finite element analyses reveal that the front propagation in the thermally anisotropic system is orientation-dependent, leading to variations in the front shape and the front velocity due to the different front-metal strip interaction mechanisms along and across the metal strips. The parameters entering the cure kinetics model used in this work are chosen to capture the key characteristics of the polymerization front, i.e., the front temperature and velocity. Numerical parametric analyses demonstrate that the front velocity in the directions parallel and perpendicular to the metal strips increases as the system size decreases and approaches the analytical prediction for homogenized systems. A two-dimensional homogenized model for anisotropic frontal polymerization in the metal-resin system is proposed.