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Date: 21-12-2019
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Waxes
Waxes are esters of fatty acids with long chain monohydric alcohols (one hydroxyl group). Natural waxes are often mixtures of such esters, and may also contain hydrocarbons. The formulas for three well known waxes are given below, with the carboxylic acid moiety colored red and the alcohol colored blue.
Spermaceti |
Beeswax |
Carnuba wax |
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CH3(CH2)14CO2-(CH2)15CH3 |
CH3(CH2)24CO2-(CH2)29CH3 |
CH3(CH2)30CO2-(CH2)33CH3 |
Waxes are widely distributed in nature. The leaves and fruits of many plants have waxy coatings, which may protect them from dehydration and small predators. The feathers of birds and the fur of some animals have similar coatings which serve as a water repellent. Carnuba wax is valued for its toughness and water resistance.
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