Sol–gel approach to the novel organic–inorganic hybrid composite films with ternary europium complex covalently bonded with silica matrix

This work successfully prepared an UV curable organic-inorganic hybrid material consisting of organic modified colloidal silica. Applications of UV curable organic-inorganic hybrid materials include abrasion resistant coatings, photo-patternable thin films and waveguides. Colloidal silica containing reactive functional groups were also prepared by reacting organic silane and tetraethyl orthosilicate (TEOS) using sol-gel process. In addition, the efficiency of grafting organic moiety onto silica nanoparticles was investigated by applying TGA and FTIR techniques. Experimental results indicated a strong interdependence between surface modification efficiency and solution pH. Acrylate-SiO2 hybrid formation could result in a shifting of thermal degradation temperature of organic component from about 200°C to near 400°C. In addition, the stability of organic modified colloidal silica in UV curable formula and the physical properties of resulting coatings were discussed. Furthermore, the morphology of organic modified colloidal silica was investigated by performing TEM and SEM studies‥

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Macrocellular Titanosilicate Monoliths as Highly Efficient Structured Olefin Epoxidation Catalysts

10.26434/chemrxiv.7578599 ◽

2019 ◽

Author(s):

Valentin Smeets ◽

Ludivine van den Biggelaar ◽

Tarek Barakat ◽

Eric M. Gaigneaux ◽

Damien Debecker

Keyword(s):

Sol Gel ◽

Silica Matrix ◽

Flow Mode ◽

Tetrahedral Coordination ◽

Excellent Performance ◽

One Pot ◽

Templating Method ◽

Porous Texture ◽

Internal Phase ◽

Epoxidation Of Cyclohexene

Self-standing macrocellular titanosilicate monolith foams are obtained using a one-pot sol-gel route and show excellent performance in the epoxidation of cyclohexene. Thanks to the High Internal Phase Emulsion (HIPE) templating method, the materials feature a high void fraction, a hierarchically porous texture and good mechanical strength. Highly dispersed Ti species can be incorporated in tetrahedral coordination the silica matrix. These characteristics allow the obtained ‘SiTi(HIPE)’ materials to reach high catalytic turnover in the epoxidation of cyclohexene. The monoliths can advantageously be used to run the reaction in continuous flow mode.<br>

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Preparation of covalently bonded silica-alginate hybrid hydrogels by SCHIFF base and sol-gel reactions

Carbohydrate Polymers ◽

10.1016/j.carbpol.2021.118186 ◽

2021 ◽

pp. 118186

Author(s):

Aurora C. Hernández-González ◽

Lucía Téllez-Jurado ◽

Luis M. Rodríguez-Lorenzo

Keyword(s):

Schiff Base ◽

Sol Gel ◽

Hybrid Hydrogels ◽

Covalently Bonded

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Significantly Improved Dielectric Performance of Poly(1-butene)-Based Composite Films via Filling Polydopamine Modified Ba(Zr0.2Ti0.8)O3-Coated Multiwalled Carbon Nanotubes Nanoparticles

Polymers ◽

10.3390/polym13020285 ◽

2021 ◽

Vol 13 (2) ◽

pp. 285

Author(s):

Lingfei Li ◽

Qiu Sun ◽

Xiangqun Chen ◽

Zhaohua Jiang ◽

Yongjun Xu

Keyword(s):

Carbon Nanotubes ◽

Dielectric Constant ◽

Energy Storage ◽

Composite Film ◽

Multiwalled Carbon Nanotubes ◽

Sol Gel ◽

Composite Films ◽

Weak Electric Field ◽

Multiwalled Carbon ◽

Dielectric Performance

The low dielectric constant of the nonpolar polymer poly(1-butene) (PB-1) limits its application as a diaphragm element in energy storage capacitors. In this work, Ba(Zr0.2Ti0.8)O3-coated multiwalled carbon nanotubes (BZT@MWCNTs) were first prepared by using the sol–gel hydrothermal method and then modified with polydopamine (PDA) via noncovalent polymerization. Finally, PB-1 matrix composite films filled with PDA-modified BZT@MWCNTs nanoparticles were fabricated through a solution-casting method. Results indicated that the PDA-modified BZT@MWCNTs had good dispersion and binding force in the PB-1 matrix. These characteristics improved the dielectric and energy storage performances of the films. Specifically, the PDA-modified 10 vol% BZT@ 0.5 vol% MWCNTs/PB-1 composite film exhibited the best dielectric performance. At 1 kHz, the dielectric constant of this film was 25.43, which was 12.7 times that of pure PB-1 films. Moreover, its dielectric loss was 0.0077. Furthermore, under the weak electric field of 210 MV·m−1, the highest energy density of the PDA-modified 10 vol% BZT@ 0.5 vol% MWCNTs/PB-1 composite film was 4.57 J·cm−3, which was over 3.5 times that of PB-1 film (≈1.3 J·cm−3 at 388 MV·m−1).

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