Computational modeling of frontal polymerization

2022-2-09
Kaya, Koray
Polymer-based composites are widely applied in high-tech areas such as aerospace, automotive, marine, and energy industries where high performance under extreme conditions is crucial. However, the traditional methods used to manufacture polymeric materials are energy-inefficient, time-consuming, complex, and costly processes. Frontal polymerization, an alternative curing method, is based on a self-propagating, self-sustained exothermic reaction front that transforms liquid monomers into cured polymers where the disadvantages of traditional polymerization techniques are minimized. Furthermore, frontal polymerization opens up new possibilities for many new manufacturing concepts such as on-demand manufacturing, on-site, shapeless production, 3-D printing, and resin-infusion. Despite the intensive studies on the chemothermal aspects of frontal polymerization, the impact of the chemical shrinkage, the sharp temperature gradients, the temperature distribution, and the front velocity on the mechanical behavior of frontally produced polymers, especially on the development of the stress accumulations, remains unexamined to a great extent. This thesis, therefore, aims to develop novel constitutive models furnished with robust computational tools to describe the coupled process of frontal polymerization and the behavior of polymeric materials produced by frontal polymerization. To this end, the thermodynamically consistent incremental framework of finite elasticity coupled with the inherent chemothermal fields is developed. In turn, this multi-field coupling allows us to calculate the accumulated stresses due to the chemically induced shrinkage and thermal expansion. Undoubtedly, the quantitative prediction of stress accumulations is of key importance to optimize the process of frontal polymerization towards the production of mechanically stronger and tougher polymer composites.

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Citation Formats
K. Kaya, “Computational modeling of frontal polymerization,” M.S. - Master of Science, Middle East Technical University, 2022.