| abstract |
Disclosed is a free radical polymerization process for the preparation of a thermoplastic resin or resins comprising heating a mixture of a free radical initiator, a stable free radical agent, and at least one polymerizable monomer compound to form a thermoplastic resin or resins with a high monomer to polymer conversion; cooling said mixture; optionally isolating the thermoplastic resin or resins; and optionally washing and drying thermoplastic resin or resins. Related free radical processes are also disclosed for the preparation of mixtures and block copolymer thermoplastic resins. Resins prepared by the disclosed processes possess a narrow polydispersity and a modality that is controlled by the selection of a free radical initiator and stable free radical agent addition step or steps. The figure is a plot of percent conversion versus molecular weight of a polystyrene homopolymer product obtained from a bulk or solventless stable free radical agent moderated polymerization of styrene at 130 degrees centigrade. |