Summary: Monodisperse thermosensitive PS‐NIPA core‐shell particles composed of a PS core and a cross‐linked PNIPA shell can be successfully synthesized by a novel method: photoemulsion polymerization. Cryo‐TEM images indicate clearly the core‐shell morphology of the PS‐NIPA particles: A homogeneous regular PNIPA shell has been affixed on the spherical PS core. DLS measurements indicate that the obtained PS‐NIPA latex particles are thermosensitive. The shell of PNIPA networks with different cross‐linking densities can shrink and re‐swell with temperature and the volume transition temperature is around 32 °C in all cases.
