Graphene, single sheets of graphite and Fullerene, where the carbon atoms are bonded together in a spherical cage. Different bonding within the structures gives rise to distinct forms with different properties. Structure of carbon allotropes Graphite Diamond Fullerene Graphene GRAPHITE: Each atom of carbon is sp2 hybridized oriented at 120 degrees, and is therefore covalently bonded 3 other carbon atoms forming hexagons in parallel layers. The weakest form of intermolecular forces, London Dispersion Forces, holds the layers together. This allows them to slide over each other.
The walls of these tubes are made up of a hexagonal lattice of carbon atoms analogous to the atomic planes of graphite. There are two types of carbon nanotubes, single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT). Single walled nanotubes (SWCNTs) consist of a single sheet of graphene rolled seamlessly to form a cylinder with diameter of order of 1 nm and length of up to centimeters. Multi-walled carbon nanotubes (MWCNTs) consist of an array of such cylinders formed concentrically and separated by 0.35 nm, similar to the basal plane separation in graphite. MWCNTs can have diameters from 2 to 100 nm and lengths of tens of microns[8].
These isomers can actually be interconverted by rotation around a single bond. Conformational isomers can be best displayed in Newman Projections. Newman Projections is defined as the representation of a molecule in which the atoms as well as bonds are viewed along the axis of rotation. The carbon in the front part of the molecule is indicated as a dot while the back one indicated using the shape of circle. The substituent on those carbon atoms can be viewed from the front and also from the back of the carbon-carbon single bond.
The aim of this essay is to explain the chemical and physical properties of carbon allotropes which are graphite, diamond, buckminsterfullerene, amorphous carbon and their applications in industry. Allotropes are element which is made up of the same material and have different ways of bonding to form different structure (NOVA 1995)(KALDOR 1988).There are four types of carbon allotropes which are diamond , graphite ,amorphous carbon and buckminsterfullerene (Evan, 2001) . Graphite is a slippery, black material which has high melting point and is insoluble in water. Therefore, graphite electrodes are used in electrochemical industries where corrosive gases are produced and used in high temperature electric furnace (Graphite, Encarta online,
Many efforts have been made in the development of new and versatile methods for various bond constructions. The advancement of coupling technology greatly affects the developments of organic synthesis, host–guest chemistry, functional materials etc. A number of coupling reactions between nucleophiles and electrophiles have been explored and
2. This implies that only one diastereomer out of the 23 possibilities is formed. Thus the aminolysis of the epoxide rings in [ZnL3]2+ by 4-substituted anilines is diastereoselective. The same diastereomers are obtained when L.H2O and L are reacted directly with Zn(ClO4)2.6H2O in tetrahydrofuran (THF) at room temperature in 70-80 % yield. L.H2O yields [ZnL3](ClO4)2.0.75THF.5H2O but L gives [ZnL3](ClO4)2.4H2O the same complex obtained by aminolysis of [ZnL3](ClO4)2.2H2O by 4-methoxyaniline in water.
INTRODUCTION Carbon nanotubes are the form of cylindrical carbon molecules and have such properties which make them potentially useful for a variety of applications. It has been used in many fields and other fields of material science carbon nanotubes are good conductors of heat and can also be synthesized as inorganic. For example such as electronics, optics, in material science carbon nanotubes are used as a minor s ratio in carbon fibers such as in Baseball Bats, Golf Clubs, Car Parts. As carbon nanotubes are good conductors of heat but as well as it is good insulators of heat along the tube axis. It is being seen that the simples one SWNT’s[singe walled nanotube] shows its conductivity along its axis 8 times more than that of copper which is well known for the thermal conduction and is has room temperature conductivity across its axis which is as thermal conductive as that of soil.
1. Introduction Carbon nanotubes (CNTs) have widely been used as reinforcement in polymer matrix–based composites. This is because of their unique properties such as mechanical, thermal, and electrical properties. In addition, carbon nanotubes have high aspect ratios and more surface area per gram which make them suitable for their use as multi-functional reinforcement materials in polymer matrixes , . The performance of a composite material system depends mainly on the interfacial properties of the reinforcement and the matrix material .
1 Development of Poly-Cyclohexanone Resin Material for Coating Applications Appala Naidu Uttaravalli*, Srikanta Dinda Dept. of Chem. Engg., BITS?Pilani Hyderabad Campus, Hyderabad ? 500078, India *Corresponding author Email: uanaiduchemz@gmail.com Abstract: In the present work, polymerization reactions of cyclohexanone were carried out in a high pressure reactor. The effect of reaction parameters such as reaction time, temperature, and catalyst loading on hydroxyl value, iodine value, solubility, and average molecular weight of products was investigated.
Effect of Different Operating Conditions on NAC Preparation The target of the present part is to discuss and evaluate the parameters affecting the preparation of AC via carbonization and activation steps, to obtain the optimum conditions for AC preparation in the nano form. The studied factors were the carbonization time, RH particle size, temperature of carbonization, solid: liquid ratio and H3PO4 concentration. 4.2.1. Effect of Carbonization Time on NAC preparation The effect of carbonization time was studied at 16 hours and 2 hours (Exp.1 and Exp. 2).