LIVING CATIONIC POLYMERIZATION OF VINYL ETHERS AND STYRENE DERIVATIVES - DESIGN OF INITIATING SYSTEMS BASED ON ADDED SALTS WITH HALOGEN ANIONS

This paper overviews three living cationic polymerization systems (for styrene, p-methoxystyrene, and isobutyl vinyl ether) that are, in common, featured by: (i) specifically in nonpolar solvents, the use of the hydrogen halide/metal halide initiating systems (HX/MX(n); X: I, Br, Cl; MX(n): ZnX2, SnCl4), which generate a living growing carbocation stabilized by a nucleophilic counteranion (X-...MX(n)); (ii) specifically in polar solvents, the use of externally added ammonium salts (nBu4N+Y-; Y-: I-, Br-, Cl-), which permit the generation of living species from HX/MX(n) by providing nucleophilic halogen anions Y-, either the same as or different from the halogen X- in HX.