| Abstract
| - The heterogeneous atom transfer radical polymerization (ATRP) of tert-butyl methacrylate(tBMA) using CuX/N,N,N‘,N‘ ‘,N‘ ‘-pentamethyldiethylenetriamine (PMDETA) catalytic system with variousinitiators R−X (X = Br, Cl) was investigated. The importance of the structure of the initiator on thepolymerization of tBMA was briefly examined. Polymerization of tBMA with ethyl 2-bromoisobutyrateresulted in uncontrolled polymerization due to slow initiation because of the low back strain effect andrelatively high propagation rate constant of tBMA. Well-controlled polymers were obtained withp-toluenesulfonyl chloride and 2,2,2-trichloroethanol initiators. This can be explained by the fast initiationcoupled with the rapid establishment of the equilibrium between the active and dormant species in thepolymerization. Poly(methyl methacrylate) macroinitiators were used to synthesize poly(tBMA-b-MMA-b-tBMA) triblock copolymers in a range of tBMA compositions. The use of a mixed halogen system in theblock copolymer synthesis leads to fast initiation and fast deactivation, resulting in controlled molecularweights and a low polydispersity index. Gradient polymer elution chromatography was used to confirmthe block copolymer structure. The retention time of the block copolymers lie in between the retentiontimes of the two homopolymers, indicating the existence of a (block) copolymer structure. This techniquewas successfully used to identify the influence of the ATRP reaction conditions on the final block copolymerstructure.
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