Esters are sweet smelling organic compounds. An ester is a derivative of a carboxylic acid except that in the ester the –OH part of the carboxylic group has been replaced by –OR group where R may be alkyl or aryl group. Esters are the most important class of acid derivatives. A large number of them occur in flowers and fruits which owe their fragrance to these compounds.
Polyester Fabric
Importance of the Esters:
The esters are very important both in the living world and in industry. The lipids that have a vital role in the structure and
metabolism of cells, as well as being used for storage and energy in the body, are esters of long–chain organic acids.
Esters are also important in the production of soaps and other detergents.
Their other major role is in the production of synthetic polymers – polyester. The polyesters are made by polymerizing diols and dicarboxylic acids to produce long–chain molecules that are unreactive and that have great tensile strength they are used widely as fibers in the production of synthetic fabrics and because of their great tensile strength, they are also used as a bonding resin in glass fiber products to give flexible strength to the material. Polyester withstands higher temperatures than most plastics so it is used in food roasting bags. Polyester fabrics such as Terylene have also had a big impact on the production of clothing. Many polyesters can be broken down by hydrolysis and so they are usually biodegradable, an important feature in an increasingly environmentally conscious world.
Polyester
Ethyl acetate can be used to make the following things:
- Artificial fruits, perfume, film, food additives, solvents (e.g. crystallization solvent) etc.
- Ethyl acetate is used as crystallization solvent since it usually does not reacts with the compound which needed to be crystallized, and it boils at low temperature (77°C).
- It usually dissolves large amount of the organic compound when it is hot but dissolves small amount of the organic compound when it is cold.
- Ethyl acetate is moderately volatile so that the final crystal can be dried readily.