scholarly journals The Effect of Catalyst in the Process of Nano-Silica Particle Formation as a Hydrophobic Material

2018 ◽  
Vol 2 (3) ◽  
pp. 152
Author(s):  
Ikhwanul Muslim ◽  
Wulan Safrihatini ◽  
Witri Aini
Keyword(s):  
Tensile Strength ◽  
Colloidal Suspension ◽  
Sol Gel ◽  
Acid Catalyst ◽  
Phase Changes ◽  
Nano Silica ◽  
Base Catalysts ◽  
Sol Gel Process ◽  
Silk Fabrics ◽  
Hydrophobic Material

<p>Nano Silica is known as a hydrophobic material used to coat the material that further modifies the surface properties of the material. In this study the process of making nano silica material is using sol-gel method. The sol gel process is defined as the process of forming an inorganic compound through chemical reaction in solution at a low temperature wherein the process a phase changes from the colloidal suspension (sol) to a continuous liquid phase (gel). The types of catalyst were studied. The result was then applied to cotton, polyamide and silk fabrics. Acid catalyst showed the greatest moisture reduction based on Moisture Content and Moisture Regain evaluation in cotton and polyamide fabrics, whereas base catalysts showed a significantly less moisture reduction on the three fabrics. The use of these types of catalyst will also affect the value of the tensile strength of each fiber. Tensile test results showed that the use of acid catalysts decreased the maximum tensile strength in cotton fabrics by 88.57%, compared to polyamide and silk fabrics and the use of base catalyst showed less significant decreased on tensile strength for all fabrics.</p>

A Preliminary Study on Cryogenic Mechanical Properties of Epoxy Blend Matrices and SiO2/Epoxy Nanocomposites

2006 ◽  
Vol 312 ◽  
pp. 211-216 ◽  
Author(s):  
Shao Yun Fu ◽  
Qin-Yan Pan ◽  
Chuan Jun Huang ◽  
Guo Yang ◽  
Xin-Hou Liu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Room Temperature ◽  
Sol Gel ◽  
Sio2 Nanoparticles ◽  
Diglycidyl Ether ◽  
Slight Reduction ◽  
Epoxy Nanocomposites ◽  
Sol Gel Process ◽  
Cryogenic Mechanical Properties

Epoxy blend matrices were prepared by incorporating polyurethane-epoxy into diglycidyl ether of bisphenol-F (DGEBF) type epoxy while SiO2/epoxy nanocomposites were made using DGEBF type epoxy and tetraethylorthosilicate (TEOS) via a sol-gel process. The mechanical properties including tensile and impact properties at 77 K of the matrices and nanocomposites were studied. The mechanical properties at room temperature were also given for the purpose of comparison with the cryogenic mechanical properties. The results showed that the incorporation of polyurethane-epoxy with a proper content into DGEBF type epoxy enhanced the mechanical properties at both room and cryogenic temperatures. Addition of SiO2 nanoparticles to DGEBF type epoxy led to significant increase in tensile strength at cryogenic temperature (77 K) while no evident change in tensile strength at room temperature. In addition, a slight enhancement by the addition of 2 wt % silica while a slight reduction by the addition of 4 wt % silica were observed in impact energy.

Synthesis of Bi4-xYbxTi3O12 Nanopowders by a Modified Sol-Gel Process

2007 ◽  
Vol 336-338 ◽  
pp. 2002-2004
Author(s):  
Xian Qun Chen ◽  
Qiu Sun ◽  
Hong Cheng Liu
Keyword(s):  
Heat Treatment ◽  
Grain Size ◽  
Bismuth Titanate ◽  
Sol Gel ◽  
Treatment Temperature ◽  
Phase Changes ◽  
Nanocrystalline Powders ◽  
Temperature Phase ◽  
Cation Substitution ◽  
Sol Gel Process

Rare earth Yb-doped bismuth titanate Bi4-xYbxTi3O12 (BYT) nanocrystalline powders were obtained by a modified sol-gel method. TG-DTA, FI-IR and XRD were used to determine the lowest heat treatment temperature. Phase changes in the formation of BYT crystalline powders were discussed by XRD. The effect of Yb3+ cation substitution for Bi3+ cation on the microstructure of BYT was also developed with XRD. The grain size of BYT nanopowders is about 40 nm determined by TEM.

Designing hierarchical porosity in tin oxide monoliths and their application as solid acid catalyst

2021 ◽  
Author(s):  
Yoshinao Suzuki ◽  
George Hasegawa ◽  
Kazuyoshi Kanamori ◽  
Kazuki Nakanishi
Keyword(s):  
Phase Separation ◽  
Tin Oxide ◽  
Solid Acid ◽  
Aprotic Solvent ◽  
Low Cost ◽  
Solid Acid Catalyst ◽  
Sol Gel ◽  
Acid Catalyst ◽  
Hierarchical Porosity ◽  
Sol Gel Process

Hierarchically porous tin oxide monoliths have been prepared from a low-cost tin(IV) chloride precursor through an epoxide-mediated sol-gel process in an aprotic solvent N,N-dimethylformamide. Phase separation is induced in the...

COTTON FABRIC PROPERTIES WITH WATER-REPELLENT FINISHING VIA SOL–GEL PROCESS

2008 ◽  
Vol 15 (06) ◽  
pp. 833-839 ◽  
Author(s):  
CHAOXIA WANG ◽  
MAO LI ◽  
MIN WU ◽  
LI CHEN
Keyword(s):  
Tensile Strength ◽  
Cotton Fabric ◽  
Abrasion Resistance ◽  
Gas Permeability ◽  
Sol Gel ◽  
Cotton Fabrics ◽  
Water Repellent ◽  
Sol Gel Process ◽  
Dyed Fabrics ◽  
Water Repellence

The properties of the cotton fabric with water-repellence finishing by sol method with the hexadecyltrimethoxysilane as additive were observed. The cotton fabrics were immersed in the prepared sols with double dip and double nip dried at 90°C, annealed at 160°C for 3 min. The water repellence and the physical properties such as gas permeability, bending properties, beetling properties, tensile strength, elongation at break, abrasion resistance, and anti-crease properties of the cotton fabrics were investigated. The results showed that anti-crease and tensile strength were improved. However, the abrasion resistance of the cotton fabrics decreased in some way. Both the bending and beetling properties measurement proved that the handle of the treated cotton fabrics changed stiffness. For the dyed fabrics by the water-repellent finishing, the hue was slightly changed, the deeper color was achieved. There is no adverse effect for treated fabric by water-repellent finishing on the fastness.

A Hydrophobic Bombyx Silk Preparation Using Sol-Gel Techniques

2011 ◽  
Vol 175-176 ◽  
pp. 276-279
Author(s):  
Yi Hu ◽  
Jing Hong Yuan
Keyword(s):  
Sol Gel ◽  
Fiber Surface ◽  
Microscopic Analysis ◽  
Lower Surface ◽  
Water Repellent ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Water Contact ◽  
Sol Gel Process ◽  
Silk Fabrics

A hydrophobic bombyx silk achieved by sol coating is characterized. The agent was firstly prepared by Dodecafluoroheptyl-propyl-trimethoxylsilane（DFS）hydrolysis, then through a sol–gel process, it coated and gelled on the fiber surface with lower surface free energy using bombyx silk fabrics as a substrate. The results of the wide-angle X-ray diffraction measurements (WAXD), TGA and DTG indicated that the thermal stability of the modified fiber was improved with the sol introduction. Scanning electron microscopic analysis (SEM) showed the morphology of the fibers in detail. The results indicated that the treated textiles had excellent water repellent property and water contact angle (CA) increased to 120.2 o.

scholarly journals Functionalization of Si-C Using TEOS (Tetra Ethyl Ortho Silica) as Precursor and Organic Catalyst

2020 ◽  
Vol 148 ◽  
pp. 07008 ◽  
Author(s):  
Riani Ayu Lestari ◽  
Muthia Elma ◽  
Erdina Lulu Atika Rampun ◽  
Anna Sumardi ◽  
Adhe Paramitha ◽  
...  
Keyword(s):  
Citric Acid ◽  
Sol Gel ◽  
Acid Catalyst ◽  
Silica Xerogel ◽  
Silica Network ◽  
Infrared Band ◽  
Oh Groups ◽  
Structured Materials ◽  
Sol Gel Process ◽  
Organic Catalyst

Silica network was tailored configuring siloxane (Si-O-Si) and silanol (Si-OH) groups which are essential to produce porous-structured materials. As silanols are hydrophilic, react with water to form fouling. This research address to actualize strategy for synthesizing highly functionalized silica carbon (Si-C) using hybrid organic-inorganic structures as the primary method for improving hydro-stability by employing precursor TEOS and organic catalyst through a sol-gel process. Catalysis employs citric acid or citric acid-ammonia whereas carbon templated into silica network. The synthesis scheme involves: a) sol-gel process at 0°C and b) calcination. Silica sol dried into xerogels were prepared and calcined at 200°C and 250°C. Characterization of xerogels showed the infrared band areas of the organic groups to evaluate the thermal stability. For xerogel employed single (pH 5.5) and dual (pH 7.65) catalyst, infrared spectra showed mostly look similar Si-C area at similar wavelength. Silica xerogel is more effectively prepared from TEOS with one-step single acid catalyst including calcination.

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