Infrared thermo-spectroscopic imaging of styrene radical polymerization in microfluidics

[Display omitted] •The integrated microscale thermal and IR spectroscopic imaging system is developed.•The concentration and thermal emission image were taken by interleaved measurement.•The styrene radical polymerization in the sapphire microfluidics is measured.•Temperature determination process in concentration distributed system is proposed.•Concentration and temperature distributions in the channel are monitored. A novel infrared (IR) thermo-spectroscopic imaging technique is applied to the simultaneous measurements of IR transmittance spectroscopic images and thermal emission images of heat and mass transfers of styrene monomer polymerization in microfluidics. The heat released is observed in the mixing layer between two laminar flows of styrene monomer and toluene containing an initiator for polymerization. The concentration of chemical species and the independently measured temperature distribution within the mixing layer are determined at the microscale. This is the first report, of such a non-invasive method, to determine both the chemical composition and temperature distribution in microfluidic chemical reactions.