In polymer chemistry, suspension polymerization is a heterogeneous radical polymerization process that uses mechanical agitation to mix a monomer or mixture of monomers in a liquid phase, such as water, while the monomers polymerize, forming spheres of polymer. The monomer droplets are suspended in the liquid phase. The individual monomer droplets can be considered as undergoing bulk polymerization. The liquid phase outside these droplets help in better conduction of heat and thus tempering the increase in temperature.