High temperature resistant silane/zirconium‐oxocluster hybrid copolymers containing “free” thiol/ene functionalities in the polymer matrix

Abstract

Inorganic-organic hybrid copolymers are promising materials where the size of the inorganic/organic domains, the phase continuity and the interface between the domains play an important role in their behavior. Two types of hybrid copolymers composed of 3-butynoate-substituted zirconium-oxoclusters covalently bonded to a (3-mercaptopropyl)trimethoxysilane or a vinyltrimethoxysilane matrix are investigated in bulk. Their properties are directly correlated with the degree of condensation of the silanes and the alkyne-3-mercaptopropyl or alkyne-vinyl interface. Both copolymers show storage moduli and glass-transition temperatures (T gG 00 ) above 130 MPa and 230 C. However, the more impressive results are achieved with the (3-mercaptopropyl)trimethoxysilane copolymer where a T gG 00 of about 300 C holds over six dynamical mechanical spectroscopy analyses. In addition to their excellent thermo-mechanical proprieties, the copolymers show unreacted 3-mercaptopropyl or vinyl groups which could be employed either in direct usage of the materials or for post-functional modifications.

(I/O) Hybrid Alkoxysilane/Zirconium-Oxocluster Copolymers as Coatings for Wood Protection

“…Both DC values were higher than the DC calculated for the copolymers in bulk. 33 The water static and vibrationally induced equilibrium (VIECA) contact angles, measured on the surface of the coated wood samples, are shown in Table 3. For each series of samples, six measurements of water static and equilibrium contact angles were performed in different points of the surface.…”

“…The 3butynoic acid, [Zr 6 O 4 (OH) 4 (O 2 CCH 2 CΞCH) 12 ], and copolymer Zr 6 / MPTMS/BPO were synthesized according to the procedure in the literature. 33,34 The wood substrates employed were wood blocks of Pinus sylvestris L. sapwood, of dimension 30 longitudinal × 10 tangential × 5 radial mm 3 , which were cut from boards with the longitudinal faces parallel to the direction of the grain. On average, the tangential direction of the wood grain intersected the 10 mm face of the samples at an angle between 30 and 45 o .…”

“…The MPTMS monomer was selected because of the high conversion rates and insensitivity to oxygen inhibition of the thiol-alkyne polymerization, as well as for the antioxidant properties of the thiol groups, 29−31 which could help to protect the wood from photodegradation and fungal decay (free radicals assist fungal decay). 32 From a previous characterization of the copolymers in bulk, 33,34 it was observed that the copolymers possess unreacted 3-mercaptopropyl or vinyl groups, even when wellformed. These can be used to introduce an extra functionality.…”

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]. …”

Stimulated Emission Depletion Lithography with Mercapto-Functional Polymers

“…We are aware that parts of the mercapto functionalized ligands participate in thiol–ene polymerization and the underlying chemistry was described before. − However, unreacted mercapto functionalized ligands remain reactive on the surface of the structure for further reactions, as will be outlined below.…”