Radical initiated heterogeneous polymerization in emulsion,dispersion and suspension is used to produce a quarter of synthetic polymers.This approach is well suited to particle formation,where various applications rely on its ability to control the uniformity,dimension and shape of the particles produced.For these heterogeneous polymerizations,emulsifiers or polymeric surfactants are needed in order to stabilize the monomer droplets,inside which the majority of the polymerization takes place.This polymerization mechanism brings about two insurmountable issues: (1) the use of such amphiphilic molecules or polymers not only affects the purity and performance of the products but also causes serious water-pollution problems;(2) since the polymerization within the monomer droplet experiences a transition from liquid to solid,it is difficult to directly obtain uniform particles.