Patent ID: 6911511

Claim:
Process for the preparation of a polymer or copolymer having a polydispersity of from about 1.8 to about 1.9, comprising a step of polymerization or copolymerization of at least one monomer via a radical route, in the presence of a polymerization or copolymerization initiator and of a stable free radical, the step being such that, per 100 mol of monomer, the following relationships are confirmed: F SFR × ( SFR ) F INIT × ( INIT ) < 0.1 ; SFR ×(SFR) ranges from 0.0001 to 0.2 mol, and further wherein F INIT ×(INIT) ranges from 0.1 to 20 mol, wherein: (SFR) represents the number of moles of stable free radical in the polymerization or copolymerization medium, F SFR represents the functionality of the stable free radical and is equal to 1 or 2, (INIT) represents the number of moles of polymerization or copolymerization initiator in the polymerization or copolymerization medium, and (F INIT ) represents the functionality of the initiator and is equal to 1.