Organic−Inorganic Poly(Methyl Methacrylate) Hybrids with Confined Polyhedral Oligosilsesquioxane Macromonomers

Abstract

We herein report the synthesis of organic−inorganic hybrid poly(methyl methacrylate) containing polyhedral oligosilsesquioxanes. Octakis(3-hydroxypropyldimethylsiloxy)octasilsesquioxane (OHPS) was synthesized from octakis(hydridodimethylsiloxy)octasilsesquioxane [Si8O12(OSiMe2H)8, Q8M8 H] following literature procedures. Octakis(methacryloxypropyldimethylsiloxy) octasilsesquioxane (OMPS) was synthesized via the reaction of methacryloyl chloride or methacrylic acid anhydride with OHPS, with the latter giving improved purity. Polymerization of OMPS with methyl methacrylate using a dibenzoylperoxide initiator gave a highly cross-linked polymer. Characterization of the polymer was performed using Fourier transform IR spectroscopy, 29Si NMR, differential scanning calorimetry, thermogravimetric analysis, atomic force microscopy, and transmission electron microscopy with energy-dispersive X-ray analysis. The polymer was found to be largely homogeneous. Increasing the OMPS concentration in the polymer gave increased decomposition and glass transition temperatures.

Polymer dynamics in rubbery epoxy networks/polyhedral oligomeric silsesquioxanes nanocomposites

“…14 Toepfer et al observed an increase of T g in PMMA-POSS hybrids. 15 Kopesky et al analyzed viscosity data in PMMA-POSS, tethered and untethered, and found a significant slowing down of chain relaxation in the first case and a decrease of viscosity, correlated with an increase of free volume, in the second case. 16 Epoxy networks modified by POSS were prepared (often by using multifunctional epoxy-POSS monomers 5,8 ) and investigated by several researchers.…”

Anticorrosive interfacial coatings for metallic substrates

“…100 It has also been shown that POSS can effectively act as a nano cross-linking agent, provided it has been functionalized, producing hybrid materials with superb structural and physical properties. 101,102 In these studies, highly cross-linked PMMA-POSS hybrids were developed by functionalizing POSS with methacryloyl groups via methacrylic acidanhydride 101 or modification of POSS-PEG with methacryloyl chloride 102 and then reacting with methacrylic monomer. Figure 15 shows all the possible structures and incorporation methods of POSS into polymer chains.…”

Silsesquioxane-based luminescent PMMA nanocomposites

“…Recently, some works on dendritic ligands based on cages, for example, β-diketone, carboxyl, and their complexes with some rare earth ions have been successfully prepared. [13][14][15] Multimethacrylate substituted cages have been synthesized by different methods, such as hydrosilylation, 16 nucleophilic substitution 17 and hydrolytic condensation, 18 and some hybrid nanocomposites have been prepared from these cage monomers via thermal polymerization [19][20][21][22] or photopolymerization. 23,24 However, these cage compounds have not been used as a ligand to coordinate with rare earth ion to form a hybrid complex containing polymerizable methacrylate group.…”