Controlled preparation of brush polymers is important in the design of functional materials. In this study, poly(tert-butyl acrylate) macromonomers functionalized with norbornenyl end group(NB-PtBA) were synthesized via atom transfer radical polymerization in three different molecular weights, 2000(NB-PtBA-2k), 3000(NB-PtBA-3k), and 8000(NB-PtBA-8k). Additionally, brush polymers with PtBA as side chains were synthesized via ring-opening metathesis polymerization(ROMP). Kinetic studies on ROMP of NB-PtBA showed that there was a ceiling degree of polymerization(CDP) for the brush polymers, beyond which the polymerization of NB-PtBA was out of control. For brush polymers of P[NB-PtBA-2k] and P[NB-PtBA-3k], CDPs were estimated to be ca. 400, but the value of P[NB-PtBA-8k] was ca. 100. Therefore, the controlled ROMP of brush polymers was critical at the CDP limit with increased macromonomer molecular weight.
Ring-opening metathesis polymerization Macromonomer Brush polymer Ceiling degree of polymeriza-tion Kinetics study
This is a preview of subscription content, log in to check access.