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.

Amphoteric polysoaps have been prepared via statistical RAFT copolymerization using either methacryloyl sulfacetamide (mSAC) or methacryloyl sulfmethazine (mSMZ) and 4-hexylphenyl methylacrylamide (4HPhMA). These copolymers form pH- and CO2-responsive polymeric micelles capable of sequestering hydrophobic molecules in water. The composition and structure of the respective copolymers can be changed to tailor the onset and extent of CO2-dependent phase behavior. When CO2 is introduced into the system, resulting in carbonic acid formation, the pH drops below the pK a of the sulfonamide units along the copolymer backbone, and phase separation occurs. Purging with N2 results in an increase in pH and redissolution of the polysoap; this process can be repeated multiple times. The mSMZ polysoaps, which show complete phase transitions using this reversible process, were especially efficient in removing the model contaminants pyrene and 9-anthracene­methanol from water. The feasibility of recovering and reusing these copolymers is demonstrated, pointing to the potential utility of such CO2-responsive systems in water treatment and related environmental remediation applications.

Recently presented as a rapid and eco-friendly manufacturing method for thermoset polymers and composites, frontal polymerization (FP) experiences thermo-chemical instabilities under certain conditions, leading to visible patterns and spatially dependent material properties. Through numerical analyses and experiments, we demonstrate how the front velocity, temperature, and instability in the frontal polymerization of cyclooctadiene are affected by the presence of poly(caprolactone) microparticles homogeneously mixed with the resin. The phase transformation associated with the melting of the microparticles absorbs some of the exothermic reaction energy generated by the FP, reduces the amplitude and order of the thermal instabilities, and suppresses the front velocity and temperatures. Experimental measurements validate predictions of the dependence of the front velocity and temperature on the microparticle volume fraction provided by the proposed homogenized reaction−diffusion model.