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Macroporous styrene‐divinylbenzene copolymers as carriers for poly(vinylamine)‐cobaltphthalocyanine oxidation catalysts

1980; Wiley; Volume: 89; Issue: 1 Linguagem: Inglês

10.1002/apmc.1980.050890117

1522-9505

Jan H. Schutten, Christianus H. Van Hastenberg, Pieter Piet, Anton L. German,

Advanced Polymer Synthesis and Characterization

Abstract Macroporous highly crosslinked styrene(St)‐divinylbenzene(DVB) copolymers were prepared by solution and suspension polymerization techniques. The obtained materials allowed the grafting of poly(N‐vinyl‐tert‐butylcarbamate) (PVCa) either by addition of VCa macroradicals to the solid bound double bonds or by termination involving the reaction of VCa macroradicals with radicals present on the carrier. Poly(vinylamine) (PVAm) grafted on St‐DVB carriers was obtained after the hydrolysis of grafted PVCa with HCl and the subsequent removal of the aminebonded HCl by means of NaOH. Heterogeneous bifunctional catalysts were obtained by attachment of cobalt(II) 4,4′,4″,4‴‐tetracarboxyphthalocyanine (CoPc(COOH) 4 ) to the grafted PVAm. The prepared catalysts were applied to the autoxidation of thiols to disulfides, both in predominantly apolar media and in aqueous media. It was demonstrated, that important prerequisites for the applicability of macroporous St‐DVB copolymers as carriers for the PVAm‐CoPc(COOH) 4 catalyst include a high surface area, a sufficiently large average pore diameter and accessibility of the pendent double bonds.