Utilization of Alkoxysilyl Groups for the Creation of Structurally Controlled Siloxane-Based Nanomaterials

Kuroda, Kazuyuki; Shimojima, Atsushi; Kawahara, Kazufumi; Wakabayashi, Ryutaro; Tamura, Yasuhiro; Asakura, Yusuke; Kitahara, Masaki

doi:10.1021/cm4023387

Cited by 96 publications

(79 citation statements)

References 79 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…are suitable for a large variety of further reactions (both HSG and NHSG condensations [29,118], hydrosilylation, co-polymerization, etc.) and therefore are very useful building blocks for the synthesis of structured silica-based materials [119]. Importantly, it was shown that these precursors can be reacted selectively and in a controlled way [117,118].…”

Section: Siloxanes By Nhsg Condensations Piers-rubinsztajn Reactionmentioning

confidence: 99%

The Power of Non-Hydrolytic Sol-Gel Chemistry: A Review

et al. 2017

View full text Add to dashboard Cite

This review is devoted to non-hydrolytic sol-gel chemistry. During the last 25 years, non-hydrolytic sol-gel (NHSG) techniques were found to be attractive and versatile methods for the preparation of oxide materials. Compared to conventional hydrolytic approaches, the NHSG route allows reaction control at the atomic scale resulting in homogeneous and well defined products. Due to these features and the ability to design specific materials, the products of NHSG reactions have been used in many fields of application. The aim of this review is to present an overview of NHSG research in recent years with an emphasis on the syntheses of mixed oxides, silicates and phosphates. The first part of the review highlights well known condensation reactions with some deeper insights into their mechanism and also presents novel condensation reactions established in NHSG chemistry in recent years. In the second section we discuss porosity control and novel compositions of selected materials. In the last part, the applications of NHSG derived materials as heterogeneous catalysts and supports, luminescent materials and electrode materials in Li-ion batteries are described.

show abstract

Section: Siloxanes By Nhsg Condensations Piers-rubinsztajn Reactionmentioning

confidence: 99%

The Power of Non-Hydrolytic Sol-Gel Chemistry: A Review

et al. 2017

View full text Add to dashboard Cite

show abstract

“…A wide variety of polyhedral oligomeric silsesquioxane (POSS)-based functional materials have been developed using ionic species. [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] We recently reported the synthesis of POSS-based ILs, and we investigated their thermal properties. 25,26 By tethering multiple ion pairs composed of imidazolium cations and carboxylates to the vertices of POSS cores or by simply adding POSS molecules with acid groups, the melting temperatures of the ion pairs decreased and their thermal stabilities increased.…”

Section: Introductionmentioning

confidence: 99%

POSS ionic liquid crystals

et al. 2015

View full text Add to dashboard Cite

Here we report the use of unique organic − inorganic hybrid materials composed of octa-substituted polyhedral oligomeric silsesquioxane (POSS) cores as ionic liquid (IL) crystals. These materials have a wide temperature range in which they exist in liquid crystal (LC) phase because of the stabilizing effect of the POSS core. We synthesized ion pairs composed of alkyl chainsubstituted imidazolium and carboxylates of various lengths that were or were not connected to the POSS core; then the thermal properties of these materials were investigated. It was found that both ion salts and the octadecyl-substituted imidazolium ion pairs with or without connection to POSS could form LCs. Interestingly, the LC phase of the POSS-tethered ion salts was maintained until decomposition. In contrast, the octadecyl-substituted imidazolium ion salts that were not tethered to the POSS core showed a clearance point during heating. The highly symmetric structure of POSS contributes not only to the suppression of the molecular motion of the ion salts, but also results in the formation of regular structures, leading to thermally stable, thermotropic IL crystals. In addition, by using electrostatic interactions originating among ionic moieties, robust chiral structures can be produced. 3,4 Even a small quantity of chiral ionic sources can efficiently induce enantiomeric structures in a bulk sample, and ionic moieties can be assembled to form regularly ordered structures. 5,6 These well-ordered ionic moieties are expected to work as efficient cation carriers and scaffolds for ordering cations. These materials, which comprise closely assembled ionic species, can exhibit interesting optical and magnetic properties. Thus, new molecular designs for preparing thermally stable LCs composed of ionic species are needed to produce advanced functional materials.The concept of supported IL phases (SILPs) has been recently proposed. Several materials based on SILPs have exhibited important characteristics such as high ion conductivity and compatibility with organic reaction media; these materials have been used as templates for the formation of nanostructures. 1 Silica supports improve the thermal stability of LCs. 7,8 Carmichael et al. 9 have synthesized and explored silicon wafer-assisted SILP materials. They created layers with thicknesses between 10 and 21 nm of an ionic LC with [C 18 C 1 Im] [PF 6 ] on the planar wafer surface and found that the ionic LC formed a mesophase. Inspired by their work, Wasserscheid et al. 7 fabricated SILP materials using silicon nanoparticles and used them as supports for preparing mesoporous structures that could act as effective gasphase catalysts. 8 To construct advanced materials based on the concept of SILP materials, their properties must be fine-tuned according to preprogramed designs at the molecular level. A wide variety of

show abstract

“…14−19 Hybrid Sibased xerogels are of particular interest because they are inexpensive and readily prepared by sol−gel processing, 20 they are heavily cross-linked, and the films can be covalently bonded to naturally stable metal oxide surfaces. 21 In addition, xerogel chemistry and topography can be adjusted by controlling substitution at the −R′ group on the (OR) 3 Si−R′ precursor(s) and the precursor molar ratios, 22 allowing one to form materials that combine the benefits of physically engineered and amphiphilic materials (vide supra). 15,19 While the AF properties and efficacy of hybrid xerogel coatings have been established in field studies, their characterization has lagged, relying primarily on atomic force microscopy (AFM) and Fourier transform infrared (FTIR) microscopy.…”

Section: ■ Introductionmentioning

confidence: 99%

Probing Nanoscale Chemical Segregation and Surface Properties of Antifouling Hybrid Xerogel Films

et al. 2015

View full text Add to dashboard Cite

Over the past decade there has been significant development in hybrid polymer coatings exhibiting tunable surface morphology, surface charge, and chemical segregation-all believed to be key properties in antifouling (AF) coating performance. While a large body of research exists on these materials, there have yet to be studies on all the aforementioned properties in a colocalized manner with nanoscale spatial resolution. Here, we report colocalized atomic force microscopy, scanning Kelvin probe microscopy, and confocal Raman microscopy on a model AF xerogel film composed of 1:9:9 (mol:mol:mol) 3-aminopropyltriethoxysilane (APTES), n-octyltriethoxysilane (C8), and tetraethoxysilane (TEOS) formed on Al2O3. This AF film is found to consist of three regions that are chemically and physically unique in 2D and 3D across multiple length scales: (i) a 1.5 μm thick base layer derived from all three precursors; (ii) 2-4 μm diameter mesa-like features that are enriched in free amine (from APTES), depleted in the other species and that extend 150-400 nm above the base layer; and (iii) 1-2 μm diameter subsurface inclusions within the base layer that are enriched in hydrogen-bonded amine (from APTES) and depleted in the other species.

show abstract

Utilization of Alkoxysilyl Groups for the Creation of Structurally Controlled Siloxane-Based Nanomaterials

Cited by 96 publications

References 79 publications

The Power of Non-Hydrolytic Sol-Gel Chemistry: A Review

The Power of Non-Hydrolytic Sol-Gel Chemistry: A Review

POSS ionic liquid crystals

Probing Nanoscale Chemical Segregation and Surface Properties of Antifouling Hybrid Xerogel Films

Contact Info

Product

Resources

About