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

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(viny1amine) (PVAm) grafted on St-DVB carriers was obtained after the hydrolysis of grafted PVCa with HCl and the subsequent removal of the aminebonded HCI by means of NaOH. Heterogeneous bifunctional catalysts were obtained by attachment of cobalt(I1) 4,4 ',4 ",4"'-tetracarboxyphthalocyanine (CoPc(COOH),)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), catalyst include a high surface area, a sufficiently large average pore diameter and accessibility of the pendent double bonds. ZUSAMMENFASSUNG: MakroporBse hochvernetzte Copolymere aus Styrol (St) und Divinylbenzol (DVB) wurden durch LBsungs-und Perlpolymerisation hergestellt. Die dargestellten Triiger erm8glichten die Pfropfung von Poly(N-vinyl-tert-butylcarbamat) (PVCa) entweder durch Addition von VCa-Makroradikalen an die am unI8slichen Triiger anhangenden Doppelbindungen oder durch Termination von VCa-Makroradikalen rnit Radikalen, die sich an der Trageroberfllche befinden. Poly(viny1amin) (PVAm) gepfropft auf St-DVB Trager wurde durch Hydrolyse von gepfropftem PVCa mit HCI und nachfolgende Entfernung von amingebundenem HCI mittels NaOH erhalten. Heterogene bifunktionelle Katalysatoren wurden dargestellt durch Bindung von Kobalt(I1) 4,4',4",4"'-tetracarboxyphthalocyanin (CoPc(COOH),) an gepfropftes PVArn. Die hergestellten Katalysatoren wurden zur Oxidation von Thiolen zu Disulfiden, sowohl in vorwiegend apolaren als auch in wurigen Ldsungsmitteln verwendet. Es wurde bewiesen, daI3 eine groDe innere Oberflkhe, ein hinreichend grol3er mittlerer Porendurchmesser und Zuglnglichkeit der anhlngenden Doppelbindungen wichtige Voraussetzungen sind fur die Anwendbarkeit vom makropordsen St-DVB Copolymeren als Trlger fur den PVAm-CoPc(COOH), Katalysator.

Phthalocyanines in Macromolecular Phases - Methods of Synthesis and Properties of the Materials

“…Other reports describe the binding of tetracarboxyphthalocyanines at linear polystyrene [111] or macroporous polystyrene grafted with poly(vinylamine), [112,113] of chlorosulfonated phthalocyanines at macroreticular polystyrene [114] and of tetrachlorocarboxyphthalocyanines at poly(c-benzyl-l-glutamate). [115] The immobilization of phthalocyanines by covalent binding to inorganic macromolecular carriers, such as silica, is a prospective approach to achieve heterogeneous catalysts and photocatalysts in which the carrier is stable against several chemicals including oxygen.…”

“…a-and b-modification are characterized by slip stack orientation of adjacent phthalocyanine rings giving distinguishable bands in the visible region. [159] The spectrum of 1 (R = H, M = Zn(II)) in Figure 7 [113,114] shows that in polymers embedded particles exhibit a different polymorphic arrangement of molecules. The amount of splitting indicates the strength of intermolecular electronic interaction thus being most intense in b-crystals, intermediate in a-crystals and weak for the zinc complex dispersed in poly(vinylidene fluoride).…”

Fabrication of Epoxide Functional Hydrophobic Composite Polymer Particles by Suspension Polymerization and Subsequent Doping with Fe³O⁴ Nanoparticles

“…The average size and coefficient of variations (CVs) are 9.44 µm and 54.88 % for P(LMA-DVB) seed particles, 8.55 µm and 20.31 % for P(LMA-DVB)/PGMA and 11.26 µm and 45.78 % for P(LMA-DVB)/PGMA/Fe 3 O 4 composite particles respectively. It is evident that seed particles have broad particle size distribution as normally observed for latex particles prepared by suspension polymerization [22][23][24][25]. Due to very high polydispersity index it is not wise to follow the increase in average particle size after seeded polymerization.…”

Quaternised poly(4-vinylpyridine) anchored on a macroporous poly(trimethylolpropane trimethacrylate-methylmethacrylate) resin, as cocatalyst in the cobaltphthalocyanine catalysed oxidative coupling of 2-mercaptoethanol

“…Schutten et al [15] suggested that the upper limit of the block length may be equated to the degree of polymerisation of the homopolymerised 4VP extracted from the resin. Viscosity measurements showed that the number average degree of polymerisation for this polymer is ~ 120.…”