N-1-alkylitaconamic acids-co-styrene copolymers. 1. Synthesis, characterization and monomer reactivity ratios

Copolymers containing N-1-ethylitaconamic acid, N-1-propylitaconamic acid, N-1-butylitaconamic acid, N-1-hexylitaconamic acid, N-1-octylitaconamic acid and N-1-decylitaconamic acid with styrene of different comonomer compositions were synthesized and characterized. Copolymer composition was determined by elemental analysis following the nitrogen content in the resulting copolymers. Monomer reactivity ratios r₁ and r₂ of the different copolymers were estimated using straight line intersection procedures such as Fineman-Ross (F-R) and Kelen-Tüdos (K-T) and by a nonlinear one, according to the reactivity ratios error-in-variables model (RREVM). Good agreement between the different procedures for r₁ and r₂ determination was found. Differences in the reactivity of N-1-alkylitaconamic acids (NAIA) relative to styrene were found i.e., ethyl and propyl derivative are less reactive with itself than butyl, hexyl, octyl, and decyl derivatives with itself. Copolymers with some tendency toward small block formation are found.