Showing posts with label Cellulose Acetate. Show all posts
Showing posts with label Cellulose Acetate. Show all posts

Wednesday, 4 November 2015

Classification of different acetates

Acetate; also known as “ethanoate” is an ester of acetic acid or a salt. Reaction of an organic acid with an alcohol forms an ester, that’s a salt. The very term “acetate” also denotes to fibres obtained from cellulose acetate commonly found over discs used in music production. There’s a variety of acetates with each having a dozen commercial and industrial applications.

1. Ethyl Acetate

When ethanol reacts with acetic acid, an ester we know as ethyl acetate is formed which is a colourless liquid with a sweet and fruity smell. Its natural occurrence exists as a derivative of wine and fruits fermentation. Synthetic production takes place in a lab following Fischer Esterification method with strong acid being a catalyst to accelerate the reaction. There’re various uses of ethyl acetate such as decaffeinating agent for coffee and tea, a preservative, production of cosmetic products, as a solvent, confectionary, perfume and paint hardener to name a few.

2. Methyl Acetate

Methyl Acetate is a pale liquid carrying a mild odour that’s achieved from reaction of methanol and acetic acid. It’s a highly volatile solvent used widely in perfume industry and is capable to dissolve various organic compounds such as polyvinyl acetate, resins, cellulose acetate, oils and fats. This volatility and solvent nature makes it a primary compound during manufacture of films, paints, lacquers and dyes.

3. Polyvinyl Acetate

Free radical polymerisation of vinyl acetate produces “Polyvinyl Acetate” that’s a vinyl polymer. Polymerisation is a process by which smaller molecules are paired to create a large chain of molecules classified as polymers. Polyvinyl acetate is actually a thermoplastic which we commonly identify as wood glue or Elmer’s glue.

4. Cellulose Acetate

Cellulose acetate is formed with reaction of cellulose, acetic acid, sulphuric acid and acetic anhydride. Further processing is executed to remove sulphates whereas product achieved is dissolved in acetone. As a result, long, fine filaments are produced that are used to create synthetic fabric. This acetate fibre is a major compound used to manufacture cigarette, furniture, fittings, clothing, upholstery and accessories. Various compounds with which we get cellulose acetate also follow a unique manufacturing cycle; for instance, acetic anhydride production!

Here’s a briefing about various types of acetates we consume frequently!