Interactions between poly(acrylamide)poly(itaconic acid) and cerium(IV)-nitrilotriacetic acid redox pair in the synthesis of acrylamide and itaconic acid homo- and copolymers

Homopolymers of itaconic acid (PIA) and its copolymers with acrylamide (P(I A-AAm) were synthesized using eerie ammonium nitrate (NH4)(2)Ce(NO3)(6) in combination with nitritotriaeetic acid (NTA) as redox initiator, and potass ium persulphate at pH 1. The chain structures of the resulting products hav e been studied by FTIR spectroscopy. It is concluded from a comparison of s pectroscopic results with gravimetric and viscometric data that the depress ions in the yields and viscosity numbers in the case of Ce(IV)-NTA redox pa ir result from interactions between the constituents of the redox initiator and IA. Spectra of the insoluble and pale yellow precipitates, which are f ormed during the first 4h of the reaction, after addition of Ce(IV) solutio n to the NTA and NTA-IA homogeneous solutions, also indicate the presence o f various oxidation products. Furthermore, it is observed that H-bonded homopolymer complex obtained from PAAm-PIA blends, prepared from aqueous solutions containing equal unit mol es of each polymer, contain both ordered and defective structures. (C) 2001 Society of Chemical Industry.