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Abstract Frontal polymerization provides a rapid, economic, and environmentally friendly methodology to manufacture thermoset polymers and composites. Despite its efficiency and reduced environmental impact, the manufacturing method is underutilized due to the limited fundamental understanding of its dynamic control. This work reports the control and patterning of the front propagation in a dicyclopentadiene resin by immersion of phase‐changing polycaprolactone particles. Predictive and designed patterning is enabled by multiphysical numerical analyses, which reveal that the interplay between endothermic phase transition, exothermic chemical reaction, and heat exchange govern the temperature, velocity, and propagation path of the front via two different interaction regimes. To pattern the front, one can vary the size and spacing between the particles and increase the number of propagating fronts, resulting in tunable physical patterns formed due to front separation and merging near the particles. Both single‐ and double‐frontal polymerization experiments in an open mold are performed. The results confirm the front–particle interaction mechanisms and the shapes of the patterns explored numerically. The present study offers a fundamental understanding of frontal polymerization in the presence of heat‐absorbing second‐phase materials and proposes a potential one‐step manufacturing method for precisely patterned polymeric and composite materials without masks, molds, or printers.
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Analytical estimates of front velocity in the frontal polymerization of thermoset polymers and composites
Abstract This note presents approximate analytical expressions for the velocity of the self‐propagating reaction front in the frontal polymerization of thermoset polymers and composites. Prior estimates available in the literature for the front velocity have been limited by their applicability to simple reaction kinetics. The improved estimates provided in this work are shown to be applicable to complex reaction kinetics encountered in the frontal polymerization of neat thermoset polymers or fiber‐reinforced polymer‐matrix composites with a wide range of polymer chemistries, including dicyclopentadiene, cyclooctadiene, acrylates, and epoxies. They are also shown to be applicable to wide range of values of the initial temperature and initial degree of cure of the resin, and of the volume fraction of the reinforcing phase.
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- PAR ID:
- 10450949
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science
- Volume:
- 59
- Issue:
- 11
- ISSN:
- 2642-4150
- Page Range / eLocation ID:
- p. 1109-1118
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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