Polycondensation of Urea and Boric Acid to Give Polyborate Ester, a Precursor for Boron Nitride

2007 ◽  
Vol 29-30 ◽  
pp. 199-202 ◽  
Author(s):  
S. Mondal ◽  
A.K. Banthia
Keyword(s):  
Boron Nitride ◽  
Boric Acid ◽  
Elemental Analysis ◽  
High Performance ◽  
Powder Processing ◽  
Condensation Reaction ◽  
Ceramic Materials ◽  
Attractive Alternative ◽  
Condensation Polymerization ◽  
Multifunctional Compounds

Polycondensations (condensation polymerization) are stepwise reactions between bifunctional or polyfunctional compoents, with elimination of simple molecules such as water or alcohol and the formation of macromolecular substances. Polyborate ester , formed by this process, gives ceramic materials during pyrolysis. Polymer pyrolysis offers an attractive alternative to the typical high temperature powder processing approach in the fabrication of high-performance ceramics. This approach might also prove to be useful in the fabrication of fibers, coatings, and composites. It is within this framework that the present study was undertaken; its aim is the preparation of boron-containing oligomeric precursors which gives boron nitride after pyrolysis. The precursor was synthesized by the condensation reaction between boric acid and urea (or other N-containing reactive multifunctional compounds). The oligomeric precursor and its pyrolysed products were thoroughly characterized by elemental analysis, IR, NMR, XRD, Thermal Analysis and Transmission Electron Microscopy(TEM). The elemental analysis results of the oligomer are---- C-13.40%, H-5.97%, N-32.44% and B-17.09%. X-ray diffraction and TEM studies showed that boron nitride obtained from this system possess tetragonal structure.

Synthesis of 3-(Cyclohexylamino)-2-arylimidazo[1,2-a]pyridine-8- carboxylic Acids Via an Efficient Three-component Condensation Reaction between Cyclohexylisocyanide and 2-Aminopyridine-3-carboxylic Acid in the Presence of Aromatic Aldehyde

2018 ◽  
Vol 21 (4) ◽  
pp. 298-301 ◽  
Author(s):  
Ghasem Marandi
Keyword(s):  
Biological Sciences ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
High Performance ◽  
Condensation Reaction ◽  
Aromatic Aldehydes ◽  
New Materials ◽  
One Pot ◽  
High Yields ◽  
Benzaldehyde Derivatives

Aim and Objective: The reaction of cyclohexylisocyanide and 2-aminopyridine-3- carboxylic acid in the presence of benzaldehyde derivatives in ethanol led to 3-(cyclohexylamino)-2- arylimidazo[1,2-a]pyridine-8-carboxylic acids in high yields. In a three component condensation reaction, isocyanide reacts with 2-aminopyridine-3-carboxylic acid and aromatic aldehydes without any prior activation. Material and Methods: The synthesized products have stable structures which have been characterized by IR, 1H, 13C and Mass spectroscopy as well as CHN-O analysis. Results: In continuation of our attempts to develop simple one-pot routes for the synthesis of 3- (cyclohexylamino)-2-arylimidazo[1,2-a]pyridine-8-carboxylic acids, aromatic aldehydes with divers substituted show a high performance. Conclusion: In conclusion, this study introduces the art of combinatorial chemistry using a simple one-pot procedure for the synthesis of new materials which are interesting compounds in medicinal and biological sciences.

scholarly journals About the possibility of creating a high-performance sensor based on boron nitride nanotubes

2020 ◽  
Author(s):  
N. P. Boroznina ◽  
M. A. Vdovin ◽  
I. V. Zaporotskova ◽  
S. V. Boroznin ◽  
P. A. Zaporotskov
Keyword(s):  
Boron Nitride ◽  
High Performance ◽  
Boron Nitride Nanotubes

Porous boron nitride: A novel metal-free cataluminescence material for high performance H2S sensing

2021 ◽  
Vol 332 ◽  
pp. 129512
Author(s):  
Yingman Bian ◽  
Li Li ◽  
Hongjie Song ◽  
Yingying Su ◽  
Yi Lv
Keyword(s):  
Boron Nitride ◽  
High Performance ◽  
Metal Free

scholarly journals Ambient-Temperature Synthesis of (E)-N-(3-(tert-Butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanimine

Molbank ◽  
10.3390/m1250 ◽  
2021 ◽  
Vol 2021 (3) ◽  
pp. M1250
Author(s):  
Diana Becerra ◽  
Justo Cobo ◽  
Juan-Carlos Castillo
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Ambient Temperature ◽  
Magnesium Sulfate ◽  
Elemental Analysis ◽  
Condensation Reaction ◽  
2D Nmr ◽  
2D Nmr Spectroscopy ◽  
Temperature Synthesis ◽  
Tert Butyl

We report the ambient-temperature synthesis of novel (E)-N-(3-(tert-butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanamine 3 in 81% yield by a condensation reaction between 3-(tert-butyl)-1-methyl-1H-pyrazol-5-amine 1 and 2-pyridinecarboxaldehyde 2 in methanol using magnesium sulfate as a drying agent. The N-pyrazolyl imine 3 was full characterized by IR, 1D, and 2D NMR spectroscopy, mass spectrometry, and elemental analysis.

Optimal plasma process routes for boron nitride (BN) powder production from boric acid (H3BO3)

2000 ◽  
Vol 26 (2) ◽  
pp. 165-170 ◽  
Author(s):  
Života G. Kostić ◽  
Predrag Lj. Stefanović ◽  
Pavle B. Pavlović ◽  
Dejan B. Cvetinović ◽  
Slobodan Đ. Šikmanović
Keyword(s):  
Boron Nitride ◽  
Boric Acid ◽  
Plasma Process ◽  
Powder Production

Influence of the Type of Dispersant on the Properties of Casting Slips of Porcelains with Soda-Lime Glass

2006 ◽  
Vol 530-531 ◽  
pp. 449-455
Author(s):  
S.R. Bragança ◽  
R. Camaratta ◽  
A.C. Taborda ◽  
C.P. Bergmann
Keyword(s):  
Slip Casting ◽  
Soda Lime ◽  
Ceramic Materials ◽  
Partial Substitution ◽  
Attractive Alternative ◽  
Soda Lime Glass ◽  
Glass Waste ◽  
Different Types ◽  
Casting Slip ◽  
Extruded Products

The use of glass residues for the reduction of firing temperature of ceramic materials products has become an attractive alternative. For pressed or extruded products, such as tiles and bricks, the use of glass is sufficiently simple, since only milling and mixing to the industrial mass batch in partial substitution of conventional fluxes are necessary. However, in slip casting products, such as china and porcelains, the glass presence destabilizes the casting slip. This is the motivation of this work. Different types of dispersants and their influence on the properties of slips containing glass waste were evaluated. The experimental results showed that the use of conventional dispersant (sodium silicate) is not adequate. The stabilization of slips was possible only with organic dispersants. Therefore, the factors that determine the success or failure of dispersants were also analyzed.

scholarly journals Effect of SiC Particulate Reinforcement in A356 / LM25 Alloy Composites and in their Hybrids

2019 ◽  
Vol 8 (2S11) ◽  
pp. 3984-3988
Keyword(s):  
Aluminium Alloy ◽  
High Performance ◽  
Hybrid Composites ◽  
Turbine Blades ◽  
A356 Alloy ◽  
Ceramic Materials ◽  
Brake Pads ◽  
Piston Cylinder ◽  
Treatment Processes ◽  
Sic Composites

LM25/A356 Aluminium Silicon alloy is characterized by high mechanical strength, corrosion resistance, machinabilty and excellent castability. Its prominent usage is found in high performance applications like in the automotive piston, cylinder blocks and heads, valve lifters, alloy wheels, brake pads and also in turbine blades. The prospects in applications of A356 are improved by heat treatment processes. Moreover the production of A356 Aluminium alloy composites renders provision for effectively tailoring the mechanical properties of the material by reinforcing the particulates of different ceramic materials at varying propositions. Although there are wide ranges of ceramic materials that could be potentially reinforced into A356 aluminium alloys, this paper exclusively reviews on SiC particulate reinforced A356 alloy composites and also its hybrid composites fabricated by strir casting method. This paper brings out the researches performed with A356/SiC composites under various experiment conditions to make this aluminium alloy available for other wide applications.

The New Technology of Precision Grinding High Performance Ceramic Materials

2013 ◽  
Vol 483 ◽  
pp. 61-64
Author(s):  
Feng Hua Kang
Keyword(s):  
High Performance ◽  
New Technology ◽  
Ceramic Materials ◽  
Precision Grinding

This paper gives further discussions refer to the precision grinding of high performance ceramic materials through the two aspects of the Grinding Properties and depth.

Synthesis and Characterization of Fluorinated Alkyl Substituted Disiloxane

2014 ◽  
Vol 529 ◽  
pp. 13-15
Author(s):  
Qing Chuan Xi ◽  
Ke Cao ◽  
Ya Wen Huang ◽  
Guan Jun Chang ◽  
Jun Xiao Yang
Keyword(s):  
High Performance ◽  
Chemical Structure ◽  
Rust Resistance ◽  
Condensation Reaction ◽  
Synthesis And Characterization ◽  
Silicon Oil ◽  
Temperature Performance ◽  
Diffusion Pump ◽  
Measurement Results

Alkyl substituted disiloxanes demonstrated promising applications as high performance hydraulic oil, diffusion pump oil, etc. In this study, fluorinated alkyl substituted disiloxane was synthesized via Grignard reaction followed by condensation reaction. Its chemical structure was verified by FTIR and NMR. Measurement results showed that this silicon oil exhibited good high temperature performance, oxidation resistance and rust resistance.

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