Surface-modified Zirconium Oxide Clusters and their Use as Components for Inorganic-Organic Hybrid Materials

Abstract

Pre-formed transition metal oxide clusters with methacrylate ligands were polymerized in the presence of organic co-monomers to form inorganic-organic hybrid polymers. The number of polymerizable ligands and thus the crosslinking density of the hybrid polymers can be varied for a given cluster type by partially exchanging the methacrylate ligands for non-reactive ones. The properties of the hybrid polymers can also be varied by adjusting the conditions of the polymerization reaction, especially by a pre-polymerization procedure. It is shown that the thermal stability of polystyrene crosslinked by Zr 6 O 4 (OH) 4 (OMc) 12 is thus greatly improved.

Oxocluster-reinforced organic–inorganic hybrid materials: effect of transition metal oxoclusters on structural and functional properties

“…were observed in many studies. [37][38][39][40][41][42][43][44][45][46][47][48][49][50][51] By the step polymerisation method implemented by Schubert and coworkers, 38,44 the Zr 6 O 4 (OH) 4 (OMc) 12 (OMc ¼ methacrylate) (Zr6) oxocluster was copolymerised with polystyrene (PS) in different amounts (0.24-0.87 mol% oxocluster proportion). The dynamic mechanical response of the hybrid was shown to be typical of thermoplastic materials.…”

Can the Clusters Zr6O4(OH)4(OOCR)12 and [Zr6O4(OH)4(OOCR)12]2 Be Converted into Each Other?

“…Partial exchange resulted in mixed-ligand clusters, which can alternatively be prepared by reaction of the metal alkoxide with mixtures of two carboxylic acids. [8,6] 4 with 10 molar equivalents of acetic acid in CH 2 Cl 2 . This Hf12 cluster is isostructural to the zirconium cluster 2 and is therefore included in the discussion.…”

“…To explore the ability of the Zr12 clusters to undergo ligand exchange reactions and to compare this with the already known exchange behavior of the Zr6 clusters [8,6] we analyzed the mixed propionate-methacrylate cluster 6. The 1 H NMR spectrum of 6 in [D 8 ]toluene at room temperature showed broad and unstructured lines, due to ligand exchange.…”

“…[1] During this work, we obtained several types of zirconium oxo clusters, among them Zr 6 O 4 (OH) 4 (OOCR) 12 (Zr6) and the dimer [Zr 6 O 4 (OH) 4 -(OOCR) 12 ] 2 (Zr12), having the same overall stoichiometry. Previous to this work, we obtained crystalline Zr6 clusters for RCOO = methacrylate (1) [2] and 5-norbornene-2-carboxylate, [3] and the Zr12 type for RCOO = acrylate.…”

Hybrid Materials Based on the Embedding of Organically Modified Transition Metal Oxoclusters or Polyoxometalates into Polymers for Functional Applications: A Review

“…Coming to the topic of this paper, and concerning the above mentioned nature of the functionalization, in the literature are reported, inter alia , oxoclusters which have been functionalized with acrylates or methacrylates [158–164,182,185–187] for free radical polymerization, norbornene-2-carboxylate derivatives for ring-opening metathesis polymerization [125], 4-pentynoate derivatives for click reactions [188], 2-bromo-isobutyrate derivatives as initiator for atom-transfer radical polymerization [189], and thiol carboxylate-substituted metal oxocluster for thiol-ene polymerization [142,190]. …”