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Free-radical suspension polymerization is a heterogeneous process in which droplets of a monomer-rich phase are dispersed in a continuous liquid phase, usually water, and polymerize by a free-radical chain mechanism. A monomer-soluble initiator generates radicals inside the droplets, so each stabilized droplet behaves approximately as a small bulk-polymerization reactor ^[1]. Protective colloids or particulate stabilizers limit droplet coalescence, while agitation and interfacial stabilization determine the droplet and final bead size distributions. Within each droplet, initiation, propagation, chain transfer, and bimolecular termination follow the usual free-radical mechanism. The product is generally obtained as polymer beads after separation from the continuous phase. Suspension polymerization differs from emulsion polymerization because initiation and principal growth occur in monomer droplets rather than in surfactant micelles or nucleated latex particles; recent reviews of aqueous dispersed radical polymerization maintain this distinction ^[2].