Novel Initiators For Atom Transfer Radical Polymerization And Synthesis Of PCL-g-PSt By Combing Ring-Opening Polymerization And Atom Transfer Radical Polymerization

This dissertation consists of the following two parts: Part I, novelinitiators for atom transfer radical polymerization; Part II, synthesis ofPCL-g-PSt by combining ring-opening polymerization (ROP) and atomtransfer radical polymerization (ATRP). In the first part, three novel initiators, 2-bromocyclohexanone,2-bromo-2-nitropropane and 2-bromo-ε-caprolactone for ATRP wereinvestigated. To our knowledge, this is the first report to usemonohaloketone and halogenated nitroparaffin as initiator for ATRP. Forall these three initiators, Mn increased with the conversion of monomerlineally, and polymers with narrow polydispersities were obtained. Theexistence of terminal Br atom was confirmed by NMR. In the second part, ring-opening copolymerization ofε-caprolactoneand 2-bromo-ε-caprolactone was carried out, giving random copolymer,poly(ε-caprolactone)-co-poly(2-bromo-ε-caprolactone). The obtainedcopolymer was used as macroinitiator for atom transfer radicalpolymerization of styrene, generating graft copolymerpoly(ε-caprolactone)-g-polystyrene with controlled molecular weight anddefined structure.