The degree of branching has an important influence on the properties.
A typical alkane paraffin wax chemical composition comprises hydrocarbons with the general formula C nH 2 n+2, such as hentriacontane, C 31H 64. Paraffin waxes are mixtures of saturated n- and iso- alkanes, naphthenes, and alkyl- and naphthene-substituted aromatic compounds. These materials represent a significant fraction of petroleum.
#Viscosity definition chemistry series#
Petroleum derived waxes Īlthough many natural waxes contain esters, paraffin waxes are hydrocarbons, mixtures of alkanes usually in a homologous series of chain lengths. This approach has relied on green chemistry approaches including olefin metathesis and enzymatic reactions and can be used to produce waxes from inexpensive starting materials like vegetable oils. Plant and animal based waxes or oils can undergo selective chemical modifications to produce waxes with more desirable properties than are available in the unmodified starting material. Other more specialized vegetable waxes include jojoba oil, candelilla wax and ouricury wax. Containing the ester myricyl cerotate, it has many applications, such as confectionery and other food coatings, car and furniture polish, floss coating, and surfboard wax. įrom the commercial perspective, the most important plant wax is carnauba wax, a hard wax obtained from the Brazilian palm Copernicia prunifera. The epicuticular waxes of plants are mixtures of substituted long-chain aliphatic hydrocarbons, containing alkanes, alkyl esters, fatty acids, primary and secondary alcohols, diols, ketones and aldehydes. Plants secrete waxes into and on the surface of their cuticles as a way to control evaporation, wettability and hydration. Lanolin is a wax obtained from wool, consisting of esters of sterols. One of its main constituents is cetyl palmitate, another ester of a fatty acid and a fatty alcohol. Spermaceti occurs in large amounts in the head oil of the sperm whale. A major component of beeswax is myricyl palmitate which is an ester of triacontanol and palmitic acid. The best-known animal wax is beeswax used in constructing the honeycombs of beehives, but other insects also secrete waxes. The composition depends not only on species, but also on geographic location of the organism.
In waxes of plant origin, characteristic mixtures of unesterified hydrocarbons may predominate over esters. Those of animal origin typically consist of wax esters derived from a variety of fatty acids and carboxylic alcohols. Waxes are synthesized by many plants and animals. Synthetic waxes often consist of homologous series of long-chain aliphatic hydrocarbons ( alkanes or paraffins) that lack functional groups. Natural waxes may contain unsaturated bonds and include various functional groups such as fatty acids, primary and secondary alcohols, ketones, aldehydes and fatty acid esters. Waxes are organic compounds that characteristically consist of long aliphatic alkyl chains, although aromatic compounds may also be present. From the Museo del Objeto del Objeto collection
Ceroline brand wax for floors and furniture, first half of 20th century.
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