Deep-sea-inspired compact flow reactor for dynamic high-temperature chemistry

While high-temperature, high-pressure water is an effective medium for inorganic synthesis, its use in constructive organic reactions is limited by thermal degradation. To overcome this limitation, we developed a compact flow reactor inspired by the dynamic thermal environment of deep-sea hydrothermal vents. The reactor enables rapid heating and quenching cycles under precisely controlled pressure, allowing precise adjustment of residence time and temperature in a benchtop system. Using acrylic acid and potassium persulfate as a model system, we demonstrated that free-radical polymerization proceeds efficiently even at 150 °C and 10 MPa, yielding poly(acrylic acid) at high conversion (∼89%) within 40 s. The combination of dynamic flow and rapid quenching limits high-temperature exposure to about 40 s, effectively suppressing thermal degradation and enabling propagation to outpace decomposition. This deep-sea-inspired strategy provides a simple, safe, and scalable method for conducting dynamic high-temperature chemistry under pressure.