scholarly journals A New Type of a Sol-Gel-Derived Inorganic-Organic Nanocomposite

1994 ◽  
Vol 346 ◽  
Author(s):  
Reiner Kasemann ◽  
Helmut K. Schmidt ◽  
Elisabeth Wintrich
Keyword(s):  
Polyethylene Oxide ◽  
Sol Gel ◽  
Scratch Resistance ◽  
Nano Composites ◽  
Nano Scale ◽  
The Matrix ◽  
New Type ◽  
Transparent Polymers ◽  
Molecular Dimensions ◽  
C Nmr

ABSTRACTA new type of sol-gel-based transparent inorganic-organic nano composites has been developed by increasing the inorganic phase dimension to values just below the point, where scattering can be neglected. For this purpose, nanosized boehmite particles ≤ 50 nm are homogeneously incorporated in a sol based on tetraethoxysilane and an epoxysilane. The nano-scale boehmite particles act as catalysts for the polymerization of the epoxy silane to polyethylene oxide, as proved by 13C NMR, and are linked to the matrix by Si-O-Al bridges, as proven by 27Al-NMR spectroscopy. The synthesized sols can be applied by standard coating techniques on transparent polymers and are cured thermally. The mechanical properties (scratch resistance, hardness) have been substantially improved compared to systems with molecular dimensions of the inorganic phase. The effect is attributed to the special structure of flexibly suspended nano-scale boehmite particles in an inorganic-organic network by a tailored interface.

scholarly journals TiO2–Polymer Nano–Composites by Sol–Gel

1995 ◽  
Vol 18 (1) ◽  
pp. 31-37 ◽  
Author(s):  
A. C. Pierre ◽  
G. Campet ◽  
S. D. Han ◽  
S. Y. Huang ◽  
E. Duguet ◽  
...  
Keyword(s):  
Composite Materials ◽  
Hybrid Materials ◽  
Polyethylene Oxide ◽  
Sol Gel ◽  
Processing Parameters ◽  
Nano Composites ◽  
Electrochemical Cells ◽  
Primary Evaluation

Sol-gel processes make it possible to develop new hybrid electrolyte materials of the type ceramic-polymer, known as Nano-Crystallite-Insertion-Material (NCIM). They can be used in reversible alkali electrochemical cells after insertion with cations such as Li+. In the present study, TiO2-polyethylene oxide hybrid materials were synthesized from TiCl4and from Ti ethoxide. Their structure is analyzed in relation with the processing parameters. A primary evaluation of the nanoscale composite materials for reversible Li insertion was performed.

Sol-Gel Synthesis of Nano-Scale, End-Member Albite Feldspar (NaAlSi3O8)

2021 ◽  
Author(s):  
L.M. Anovitz ◽  
A. Affolter ◽  
M.C. Cheshire ◽  
A.J. Rondinone ◽  
Lawrence F. Allard
Keyword(s):  
Sol Gel ◽  
Nano Scale ◽  
Sol Gel Synthesis

Synergistic Effect of Eu3+ and Sm3+ Co-Doping on Photocatalytic Activity of TiO2 Nanoparticles

2011 ◽  
Vol 197-198 ◽  
pp. 891-894 ◽  
Author(s):  
Cheng Zhi Jiang ◽  
Xu Dong Lu
Keyword(s):  
Photocatalytic Activity ◽  
Synergistic Effect ◽  
Sol Gel ◽  
Blue Shift ◽  
Nano Particles ◽  
Absorption Profile ◽  
Co Doping ◽  
The Matrix ◽  
Co Doped ◽  
The Eu

Pure TiO2, Eu3+and Sm3+co-doping TiO2composite nanoparticles have been prepared by sol-gel method and characterized by the techniques such as XRD, SEM and DRS. The photocatalytic degradation of methylene blue (MB) in aqueous solution was used as a probe reaction to evaluate their photocatalytic activity. The matrix distortion of TiO2nano-particles increases after co-doping of Eu3+and Sm3+and a blue-shift of the absorption profile are clearly observed. The results show that co-doping of Eu3+and Sm3+inhibits the phase transformation of TiO2from anatase to rutile, decreases the diameter of TiO2nano-particles and significantly enhance the photocatalytic activity of TiO2. The Eu3+and Sm3+co-doped into TiO2nano-particles exert a synergistic effect on their photocatalytic activity.

A New Design of a Piezoelectric Triaxial Micro-Accelerometer

2015 ◽  
Vol 645-646 ◽  
pp. 841-846 ◽  
Author(s):  
Jian Yan Wang ◽  
Ting Ting Wang ◽  
Hang Guo
Keyword(s):  
Simulation Analysis ◽  
Structural Parameters ◽  
Sol Gel ◽  
Triaxial Accelerometer ◽  
Response Frequency ◽  
Pzt Films ◽  
New Type ◽  
The Cross ◽  
Cross Axis ◽  
Micro Accelerometer

Accelerometer in MEMS always is made by capacitive or piezoresistive, whose dynamic response is not good, the operating frequency is narrow, and the cross-axis sensitivity is low. A new type of piezoelectric micro-accelerometer is designed, and its structure is “x” type. The sensing unit is piezoelectric PZT films, which is achieved by sol-gel method. The accelerometer is a triaxial accelerometer. The theoretical and simulation analysis is used to achieve the charge sensitivity and response frequency, and also get the optimal structural parameters. A new circuit connection is proposed to improve the sensitivity and avoid the cross-axis sensitivity. The design achieves the z-axis sensitivity with more than 40 pC/g, x, y-axis sensitivity with more than 8pC/g, and the response frequency is about 3000Hz.

scholarly journals New approach to the formation of organo-inorganic borosyloxane polymer structures

2019 ◽  
Vol 57 (2) ◽  
pp. 35-40
Author(s):  
Alexander B. Zachernyuk ◽  
◽  
Boris A. Zachernyuk ◽  
Ekaterina N. Solovyova ◽  
Vladimir I. Nedelkin ◽  
...  
Keyword(s):  
Boron Oxide ◽  
Sol Gel ◽  
Thermal Characteristics ◽  
Inorganic Materials ◽  
Organic Modifiers ◽  
Synthesis Time ◽  
Transparent Films ◽  
Boric Anhydride ◽  
The Matrix ◽  
Synthetic Approaches

Using sol-gel methods, new synthetic approaches to the preparation of boron-containing organic-inorganic hybrid polymers based on boron oxide (boric anhydride), which is a part of many inorganic materials, have been developed. Previously, such methods were used to obtain amorphous silicate glasses and their use allows introducing various inorganic and organic modifiers into the matrix of silicon dioxide and other compounds at temperatures up to 120 °C. Within the framework of this work: a) the conditions for obtaining saturated solutions of boron oxide in organic solvents were found and it was found that boric anhydride is most completely dissolved in triethyl orthoformiate (approximately 25%) at 110-110 °C retaining its structure; b) by the condensation of boric acid with 1,3-dichlorotetraphenyl disiloxane, functional borcyclosiloxanes were synthesized to further modify boron oxide. The reaction conditions, spectral and thermal characteristics of condensation products were investigated. It is shown the increasing in the synthesis time to 15-18 h, a bicyclic borsiloxane is formed; c) homophasic modification of boric anhydride with monofunctional cyclic borsiloxanes was carried out and it was shown that the formation of Si-O-B bonds at 110-120 °C occurs due to the use of anhydrous sol-gel process. Transparent films are obtained from modified boric anhydride solutions deposited on glass and stainless steel, followed by curing at a temperature of 160-280 °C, that are not subjected to hydrolysis under the action of air moisture and are stable in air up to 600 °C. As a result of the work, the possibility of obtaining a borsiloxane type polymeric structures having an inorganic molecular skeleton modified with organosilicon compounds has been investigated.

scholarly journals Cyanate Ester Resin/Silica subnanocomposites and their superiority over nanocomposites due to fundamental role of constrained interfacial dynamics

2021 ◽  
Vol 2103 (1) ◽  
pp. 012100
Author(s):  
V A Bershtein ◽  
A M Fainleib ◽  
D A Kirilenko ◽  
P N Yakushev
Keyword(s):  
Positive Impact ◽  
Sol Gel ◽  
Cyanate Ester ◽  
Interfacial Dynamics ◽  
Cyanate Ester Resin ◽  
Sol Gel Process ◽  
Matrix Properties ◽  
Interfacial Areas ◽  
The Matrix

Abstract The study of nanostructure, thermal and relaxation properties (by HAADF-STEM, EDXS, DMA and DSC), combined with the calculations of interparticle distances and interfacial areas, has been performed for a series of the hybrid Cyanate Ester Resin (CER)/Si02 polymer composites with 0.01 to 10 wt.% Si02 units introduced via a sol-gel process. The absence of clusterization, arising only subnanometric Si02 nodes and their quasi-regular distribution within the amorphous matrix, with the shortest distances between nodes, provided their exceptional positive impact on the matrix properties at ultra-low Si02 contents of 0.03-0.1 wt.%. The superiority of these subnanocomposites over the nanocomposites was determined by the role of constrained interfacial dynamics over the whole matrix.

scholarly journals Micro Hardness and Erosive Wear Behavior of Tungsten Carbide Filled Epoxy Polymer Nano Composites

2020 ◽  
Vol 5 (3) ◽  
pp. 405-415
Author(s):  
M. Kameswara Reddy ◽  
V. Suresh Babu ◽  
K. V. Sai Srinadh
Keyword(s):  
Tungsten Carbide ◽  
Polymer Nanocomposites ◽  
Adhesive Bonding ◽  
Epoxy Polymer ◽  
Wear Behavior ◽  
Erosive Wear ◽  
Nano Composites ◽  
Erosion Wear ◽  
Wear Properties ◽  
The Matrix

The present work studies the tribological performance of Tungsten Carbide (WC) nanoparticles reinforced epoxy polymer nanocomposites. Polymer nanocomposites are prepared by hand lay-up method. Erosive wear and hardness tests were conducted to examine the physical and wear properties of epoxy/WC nanocomposites. Addition of WC nanoparticles led to significant reduction in erosion rate. In addition to that, incorporation of WC nanoparticles enhanced the hardness of epoxy nano composites. At 2% weight of WC nano filler, nanocomposites showed better performance in erosion wear properties and also in hardness. While at 3wt% of WC filler, least performance in hardness was caused by the weak adhesive bonding between the matrix and filler. The nature of erosion wear behavior was observed. Finally worn surfaces of nanocomposites were inspected using a “scanning electron microscope (SEM)”.

scholarly journals A Novel Amperometric Biosensor Based on Poly(allylamine hydrochloride) for Determination of Ethanol in Beverages

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6510
Author(s):  
Oana Maria Istrate ◽  
Lucian Rotariu ◽  
Camelia Bala
Keyword(s):  
Good Accuracy ◽  
Sol Gel ◽  
Storage Conditions ◽  
Applied Potential ◽  
Screen Printed Electrode ◽  
Response Range ◽  
New Type ◽  
Allylamine Hydrochloride ◽  
Working Parameters

Herein, we report on a new type of ethanol biosensor based on a screen-printed electrode modified with poly(allylamine hydrochloride). The alcohol dehydrogenase was immobilized on the surface of the sensor using the sol–gel matrix. Working parameters such as applied potential, pH, NAD+ concentration, storage conditions were optimized. A response range between 0.05 and 2 mM was found with a sensitivity of 13.45 ± 0.67 µA/mM·cm2 and a detection limit of 20 µM. The developed biosensor was used to detect ethanol in commercial beverages with good accuracy.

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