The role that esters play in society
The word ester was first used in the late 19th century by the German chemist Leopold Gmelin. www.encyclopedia.com
Esters are all around us, when you smell flowers and fruits, you smell esters, our body’s genetic makeup, the phosphoesters are the backbone of DNA, and esters are used for making material, esters are used as surfactants namely soap and detergents and polyesters are used to make plastics. Esters are naturally occurring pheromones, esters are found in vegetable oil and animal fat, nitrate esters are used to make explosives. Esters are organic compounds that have a wide application in the worlds of medicine, biological materials, industrial and organic chemistry. Esters are naturally occurring compounds. Esters have the general formula of RCOOR, where the two R’s represent organic radicals. We need and use esters every day. www.chemguide.co.uk
An ester is an organic compound, it is produced when a carboxylic acid, the carboxylic acid contains a COOH group, in esterfication the hydrogen is
…show more content…
Polyethylene terephthalate is used as textile fibres and we know them by the following names Terylene, and Dacron, to name two. It consists of a synthetic polymer that is made out of a purified terephthale acid or its dimethyl ester, dimethyl terephthalate and mono ethylene glycol. Today 18% of the market shares of all plastic materials produced is polymers from dicarboxylic acid and a diol. There are many applications and depends on the production and orientation of the polymer chains. Also used in textiles and food packaging, maybe you will recognise the trivial name, polyethylene terephthalate, PET. The annual production is about 40 million tonnes; of this 40 million tonnes 65% is for fibres production, 5% for film production, and 30% for packaging material. These polymers do not discolour in light and their melting point is high
The experimental Fischer esterification of 8.92g of acetic acid with 5.0g of isopentyl alcohol using concentrated sulfuric acid as a catalyst yielded 4.83g (65.3% yield) of isopentyl acetate. The product being isopentyl acetate was confirmed when the boiling point during distillation had similar characteristics to that of the literature boiling points2. Physical characteristics like color and smell also concluded a match of our product with what was intended. 1H-NMR spectroscopy analysis supported this claim due to the fact that the integration values and chemical shifts were comparable to isopentyl acetate. Lastly, infrared spectroscopy (IR) showed similar key characteristics of our product’s wavelengths to that of pure isopentyl acetate5.
The most classic and standard procedure for producing esters is the Fisher-esterification reaction. Discovered in 1895 by German chemists Emil Fischer and Arthur Speier 4, this reaction involves refluxing a carboxylic acid and an alcohol in the presence of an acid catalyst. In order to drive the equilibrium towards the products, the water from the dehydration process must be removed and there must be an excess amount of alcohol. A vast range of carboxylic acids may be used for this reaction however the type of alcohols are limited. Primary and secondary alcohols are most frequently used in esterification reactions, tertiary alcohols are steric ally hindered usually resulting in poor yields5 and tend to undergo elimination reactions instead. In this rea...
Biological waxes are esters of long-chain (C14 to C36) saturated and unsaturated fatty acids with long-chain (C16 to C30) alcohols. Their melting points (60 to 100 _C) are generally higher than those of triacylglycerols.In plankton, the free-floating microorganism sat the bottom of the food chain for marine animals, and waxes are the chief storage form of metabolic fuel. Waxes also serve a diversity of other functions related to their water-repellent properties and their firm consistency. Certain skin glands of vertebrates secrete waxes to protect hair and skin and keep it pliable, lubricated, and waterproof. Birds, particularly waterfowl, secrete waxes from their preen glands to keep their feathers water-repellent. The shiny leaves of holly, rhododendrons, poison ivy, and many tropical plants are coated with a thick layer of waxes, which prevents excessive evaporation of water and protects against parasites. Biological waxes find a variety of applications in the pharmaceutical, cosmetic, and other industries. Lanolin (from lamb’s wool), beeswax carnauba wax (from a Brazilian palm tree), and wax extracted from spermaceti oil (from whales ;)
amount of ester but with water added in, which gives us a good amount of product,
Fatty acids such as linoleic acid, linolenic acid and arachidonic acid are known as essential fatty acid because they cannot be synthesized in the body so must be supplied in the food. Human being lacks the ability to introduce double bonds in fatty acids beyond carbons 9 & 10. About 20 different fatty acids are synthesized from the two essential fatty acids linoleic acid and linolenic acid. Omega three fatty acid is synthesized from linolenic acid and omega six fatty acid is synthesized from linolic acid.
Before using ethylene to produce polyethylene, the compound needs to be purified to almost 100%. In order to reach this level of purity the ethylene needs to be freed of olefins, acetylenes, dienes and water through several processes such as: driers are used to take out the water, a demethanizer is used to remove methane, etc. ...
Service life The effect of fillers on polymers is that they are very beneficial because they don’t get ruined for a long time. Glass fillers are the most commonly used fillers in polymers. This is because they last longer and their service life is longer.
Unlike most hydrocarbons, cholesterol does not have an alternative name; it is simply cholesterol. The formula for cholesterol is C27H46O and the structure is on the cover page of this document. The “-ol” in cholesterol implies that it is part of the hydroxyl or alcohol functional group. Being part of the alcohol functional group means that one of the parent hydrocarbons was replaced with the alcohol functional group –OH.
There were many things that I learned in Module 7 . Some of them where: what is the difference between an acid and a base; what is pH; what is equilibrium, what is Le Châtelier’s principle; and what is oxidation. Here are some of the things that I learned in lesson 07.01 (Acids and Bases) and lesson 07.02 (Acid-Base Reactions).
The synthesis of polymers starts with ethylene, (or ethene). Ethylene is obtained as a by-product of petrol refining from crude oil or by dehydration of ethanol. Ethylene molecules compose of two methylene units (CH2) linked together by a double carbon
Polymer-Polyethylene is partially crystalline as well as amorphous because it has crystalline and amorphous regions. Also it has linear chains so this is the simplest structure compared to a branched or network chain. This can be of an advantage to it over other types of materials as its good toughness and elongation makes it very significant in the engineering industry as it can be moulded or extruded into shape...
Methyl butyrate or methyl ester of butyric acid is an ester with a fruity odor of pineapple, apple and strawberry. Present in small amounts in several plant products, especially pineapple flavor is produced by distillation from essential oils of vegetable origin. This ester is also manufactured on a small scale for use in perfumes or food flavors. Esters, in general, can be defined as the reaction products of carboxylic acids and organic alcohols. Chemically, an ester is the condensation product that results when a carboxylic acid is reacted with an alcohol1. Esterification of carboxylic acids with alcohols represents a well-known category of liquid-phase reactions of considerable industrial interest due to enormous practical importance of organic ester products. Esters are important fine chemicals used widely in the manufacturing of flavors, pharmaceuticals, plasticizers, solvents of paints, adhesives, pesticides, polymerization monomers and in the preparation of biodiesel from lower quality feedstock. Derivatives of some esters are useful as chemical intermediates and monomers for resins and high molecular weight polymers. They are also used as emulsifiers in the food and cosmetic industries2, 3.
Fatty acids are another type of lipid. The common feature of fatty acids is that they are all esters of moderate to long chain fatty acids. Two polyunsaturated fatty acids, linoleic and linoleic, are designated "essential" because their absence in the human diet has been associated with health problems, such as scaly skin, stunted growth and increased dehydration. These acids are also precursors to the prostaglandins, a family of physiologically potent lipids present in minute amounts in most body tissues.
Acids such as nitric acid, sulfuric acid, phosphoric acid have countless uses in industrys. Soe acids like acetic acid or the phosphoric acid in soft drinks are sold as consumer products. Other acids are used on synthesis of dyes, fertilizers, explosives, and many other chemical substances that are essential in our lives
used to make products such as plastic lumber, toys, containers, carpet, fiber fill for jackets