Amines release from schiff bases polymers and diffusion from dosage forms with eudragit RL in acidic medium

Chloromethylstyrene 1 (mixture meta and para; 60/40) can be oxydized in corresponding aldehyde 2. Vinylbenzaldehyde 2 reacts with primary amines such as aniline, benzylamine, 2‐phenylethylamine, 3‐phenylpropylamine, and 2‐aminopyridin to give Schiff bases that are polymerized in bulk with a radical initiator. Poly(vinyl benzaldehyde) 6 prepared from corresponding monomer 2 also reacts with primary amines to give polymeric Schiff bases. Hydrolyses of these polymeric imines have been carried out either in heterogeneous acidic medium or basic heterogeneous medium; a suitable percentage of amines has been released after some hours. Finally, a study of hydrolysis and of diffusion of released amines in a dosage form (Eudragit RL) has been also carried out with some polymeric Schiff bases.