2-vinylpyridine-co-N-vinyl-2-pyrrolidone and 4-vinylpyridine-co-N-vinyl-2-pyrrolidone copolymers: Synthesis and reactivity ratios

Copolymers containing 2-vinylpyridine (2VPy) and 4-vinylpyridine (4VPy) with N-vinyl-2-pyrrolidone (VP) (2VPy-co-VP and 4VPy-co-VP, respectively) were synthesized and characterized. Copolymers with different compositions were obtained. The reactivity ratios were estimated by using the classical Finemann-Ross and Kelen Tüdos linear procedures. These parameters were also estimated by using a computer program based on a non-linear minimization algorithm (NLMA), starting from the values of r₁ and r₂ obtained by the above linear procedures. Random Copolymers with zones containing vinylpyridine blocks were obtained.