Copolymer vinylimidazole, synthesis

This strategy was first realized by Lozinsky et al., who studied the redox-initiated free-radical copolymerization of thermosensitive N-vinylcaprolactam with hydrophilic N-vinylimidazole at different temperatures, as well as by Chi Wu and coworkers. Lozinsky presents an extensive review of the experimental approaches, both already described in the literature and potential new ones, to chemical synthesis of protein-like copolymers capable of forming core-shell nanostructures in a solution. 

The synthesis of a well defined block copolymer, containing a poly(N-vinylimidazole) block (PVim), has been demonstrated by Ge et al. [23]. The polymerization was realized via a RAFT procedure employing xanthates as chain transfer agents. Initially, the polymerization of NIPAM monomer, affording PNIPAM macro-CTA, was realized followed by the polymerization of Vim, Figure 4. The obtained block copolymers had controllable molecular characteristics with a Mw/M value ca. 1.2. The living nature of the Vim polymerization has been confirmed by kinetic experiments, for the first 150 min of the polymerization reaction. It has to be noted that the above procedure was the first example of the synthesis of PVim containing block copolymers. 

The microgel particles used in present study are based on copolymer of vinylcaprolactam (VCL) and acetoace-toxye yl methacrylate (AAEM). As described in our previous studies the microgel particles possess heterogeneous stmcture and consist of AAEM-rich core and VCL-rich shell due to some peculiarities of the polymerization process [30], The use of small fraction of vinylimidazole (Vim) during VCL/AAEM microgel synthesis allows selective incorporation of Vim units in the... 

Bozknrt A, Karadedeli B (2007) Copolymers of 4(5)-vinylimidazole and ethyleneglycol methaoylate phosphate synthesis and proton ctmductivity properties. React Funct Polym 67 348-354... 

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