Morphology and radical reactions of Cu(II) and Co(II) sulfonated phthalocyanines covalently linked to poly(ethylenamide)

The tetrasulfonated Cu II ( tspc ) 4- , tspc = 4,4′,4″,4‴-phthalocyaninetetrasulfonate, and the trisulfonated Co II ( trspc ) 3- , trspc = n , n ′, n ″-phthalocyanine-trisulfonate and n, n′ and n″ indicate the sulfonated positions of the various isomers, were covalently linked to a polyethyleneimine, M n ~ 10000 and M w ~ 25000, backbone. A fraction of the amine groups in a strand was converted to Cu II pc (- SO 3 ) 3 (- SO 2 N <) \3- or Co II pc (- SO 3 ) 2 (- SO 2 N <) \2- pendants and the remaining were acetylated. Strands of the polymers, poly(K 3 Cu II tspc) and poly(K 2 Co II trspc) , formed spherical bundles with diameters ~1000 nm for poly(K 3 Cu II tspc) and ~100 nm for poly(K 2 Co II trspc) . The stability of the bundles is metal-dependent. Poly(K 2 Co II trspc) forms the most stable bundles with respect to hydrolytic and redox reactions. ESR and optical spectroscopies as well as reactions of the pendants with pulse radiolytically generated radicals, namely e - sol , C • H 2 OH, (CH 3 ) 2 COHC • H 2 , CO 2 •- , N 3 • and SO 4 •- , revealed a distribution of pendants between isolated and aggregated forms in a bundle. The reduction of the Cu(II) to Cu(I) in aqueous solutions of the poly(K 3 Cu II tspc) was associated with pendants present in a mostly hydrophobic environment. Unstable phthalocyanine pendants with Co III -carbon bonds are formed when Co II pc(-SO 3 ) 2 (-SO 2 N<) \2- reacted with C -centered radicals, ( CH 3 ) 2 COHC • H 2 and C • H 2 OH . The species with Co III -carbon bonds were precursors to the formation of Co I pc(-SO 3 ) 2 (-SO 2 N<) \3- pendants. The redox reactions of the pendants in these polymers are compared with those of K 4 Cu II tspc and K 3 Co II trspc .