Candle is a diverse class of lipophilic, solid organic compounds that can be formed near ambient temperature. They include higher alkanes and lipids, usually with a melting point above about 40 Ã, Â ° C (104Ã, Â ° F), melting to provide a low viscosity liquid. The wax is not soluble in water but dissolves in nonpolar organic solvent. Natural waxes of various kinds are produced by plants and animals and occur in petroleum.
Video Wax
Chemistry
Candles are organic compounds typically composed of long alkyl chains. They may also include various functional groups such as fatty acids, long chain alcohols and secondary, unsaturated, aromatic, amide, ketone, and aldehyde bonds. They often contain fatty acid esters as well. Synthetic waxes are often long-chain hydrocarbons (alkanes or paraffins) that do not have functional groups.
Plant and animal wax
Candles are synthesized by many plants and animals. Those derived from animals usually consist of wax esters derived from various carboxylic acids and fatty alcohols. At night the origin of the plant, a mixture of non-esterified hydrocarbon characteristics can predominate the esters. Its composition depends not only on the species, but also on the geographical location of the organism.
Animal candle
The best known animal wax is beeswax, but other insects release (release) the wax. The main component of beeswax used in building honeycomb is the myricyl palmitate esters which are esters of triacontanol and palmitic acid. The melting point is 62-65 Â ° C. Spermaceti occurs in large amounts in sperm whale oil. One of the major constituents is cetyl palmitate, another ester of fatty acids and fatty alcohols. Lanolin is a wax obtained from wool, which consists of a sterol esters.
Planting candles
Plants excrete waxes in and on the surface of their cuticles as a way to control evaporation, wettability and hydration. The epiduric wax plant is a mixture of a substituted long-chain aliphatic hydrocarbon, containing alkanes, alkyl esters, fatty acids, primary and secondary alcohols, diols, ketones, aldehydes. From a commercial perspective, the most important wax of plants is carnauba wax, a hard wax obtained from Brazilian Coppericia prunifera. Containing myricyl cerotate ester, it has many applications, like confectionery and other food coatings, car polish and furniture, yarn layers, and surfboard candles. Other special vegetable candles include candelilla candles and ouricury candles.
Modified plant and animal wax
Plant and animal waxes and oils may undergo selective chemical modification to produce waxes with more desirable properties than those available in unmodified starting materials. This approach relies on green chemical approaches including metathesis olefins and enzymatic reactions and can be used to produce waxes from inexpensive starting materials such as vegetable oils.
Petroleum-derived wax
Although many natural waxes contain esters, paraffin wax is a hydrocarbon, a mixture of alkanes usually in a series of long chain homologues. These materials represent most of the petroleum. They are refined with a vacuum distillation. Paraffin wax is a mixture of saturated aromatic compounds n- and iso-alkanes, naphthen, and alkyl and naphthen-substituted. The chemical composition of typical paraffin alkane waxes comprises hydrocarbons of the general formula C n H 2 n 2 , such as Hentriacontane, C 31 H 64 . The level of branching has an important influence on the property. Microcrystalline waxes are lower-wax petroleum-based waxes containing higher percentages of isoparaffinic (branched) hydrocarbons and naphthenic hydrocarbons.
Millions of tons of paraffin wax are produced every year. They are used in foods (such as chewing gum and cheese wrappers), in wax and cosmetics, as a nonstick coating and waterproof and in polish.
Lilin Montan
The Montan candle is a wax fossil extracted from coal and lignite. It is very hard, reflecting the high concentration of saturated fatty acids and alcohols. Although dark brown and smelly, they can be purified and bleached to provide commercially useful products.
In 1995, about 200 million kilograms/year was consumed.
Polyethylene wax is made with one of three methods: 1- direct polymerization of ethylene (may include co-monomers as well); 2 - thermal degradation of high molecular weight polyethylene resins; 3 - recovery of low molecular weight fractions from production of high molecular weight resins.
Each production technique produces products with slightly different properties. The key properties of low molecular weight polyethylene wax are viscosity, density and melting point.
Polyethylene wax produced by degradation or recovery from polyethylene resin stream contains very low molecular weight material that must be disposed to prevent volatilization and potential fire hazards during use. The polyethylene wax produced by this method is usually stripped from a low molecular weight fraction to generate a flash point & gt; 500 Â ° F (& gt; 260 Â ° C). Many polyethylene resin plants produce low molecular weight streams commonly referred to as Low Polymer Wax (LPW). LPW is not purified and contains volatile oligomers, corrosive catalysts and may contain other foreign materials and water. The purification of LPW to produce polyethylene wax involves removing oligomers and dangerous catalysts. Proper purification of LPW to produce polyethylene wax is essential when used in applications requiring FDA or other regulatory certification.
Maps Wax
Usage
The wax is mainly consumed by industry as a complex formulation component, often for coating. The main use of polyethylene and polypropylene waxes is in the dye formulations for plastics. Candles give the effect of webbing and wear resistance to paint. Polyethylene wax is inserted into the ink in the form of dispersion to reduce friction. They are employed as release agents, finding use as slip agents in furniture, and providing corrosion resistance.
Candle
Candles such as paraffin wax or beeswax, and hard fat such as fat are used to make candles, used for lighting and decoration.
Candle products
Candles are used as the final coating and coating for wood products. Beeswax is often used as a lubricant on the slide of the drawer where the wood contact to the wood occurs.
Other uses
The sealing wax was used to cover important documents in the Middle Ages. Wax tablets are used as writing surfaces. There are various types of candles in the Middle Ages, namely four types of candles (Ragusan, Montenegro, Byzantium, and Bulgaria), "ordinary" candles from Spain, Poland and Riga, unrefined candles and colored candles (red, white, and black). green). Candles are used to make wax paper, impregnate and coat paper and card to make it waterproof or make it resistant to stains, or to modify its surface properties. Candles are also used in shoe polish, wood polish, and automotive polishing, as a mold release agent in mold making, as a coating for many cheeses, and for leather and waterproof fabrics. Candles have been used since time immemorial as a temporary model that can be removed on casting of gold, silver, and other lost-wax materials.
Candles with colorful pigments added have been used as media in encaustic painting, and are used today in the manufacture of crayons, china markers and colored pencils. The carbon papers, used to make duplicate typed documents are coated with black carbon suspended in wax, are usually montan candles, but have largely been replaced by photocopiers and computer printers. In other contexts, lipstick and mascara are a mixture of various fats and candles stained with pigments, and both beeswax and lanolin are used in other cosmetics. Ski wax used in skiing and snowboarding. In addition, surf and skateboard sports often use candles to improve performance.
Some candles are considered safe for food and used to coat wood cutting board and other items that come into contact with food. Beeswax or colored synthetic candles are used to decorate Easter eggs in Romania, Ukraine, Poland, Lithuania and the Czech Republic. Paraffin wax is used to make chocolate candy.
Candles are also used in wax candles, which are used as auxiliary tools.
Specific examples
Night animals
- Beeswax - produced by honey bee
- Chinese candles - produced by scale insects Ceroplas ceriferus
- Lanolin (wool wax) - from the sebaceous glands
- The wax candle - from insect lacca Kerria lacca
- Spermaceti - from the sperm's head and fat cavity
Vegetable candles
- Bayberry wax - from the fruit surface wax from bayberry bush, Myrica faya
- Candle wax - from the Mexican bush Euphorbia cerifera and Euphorbia antisyphilitica
- Carnauba candles - from carnauba palm leaves, Copernicia cerifera
- Castings of castings - hydrogenated catalyst distance oil
- Esparto candles - byproducts of esparto grass, ( Macrochloa tenacissima )
- Japanese candle - vegetable triglyceride (not original candle), from berry fruit Rhus and Toxicodendron species
- Our candle candles - from the Brazilian fur palm, Syagrus coronata .
- Bran rice bran - obtained from rice bran ( Oryza sativa )
- Soy candles - from soy oil
- Tallow candle - from tallow seed Triadica sebifera .
Mineral candle
- Ceresin wax
- The montan wax - extracted from lignite and brown coal
- Ozocerite - found in lignite beds
- Peat candle
Petroleum wax
- Paraffin wax - made of long chain alkane hydrocarbons
- Microcrystalline wax - with a very fine crystal structure
Also see
- Melting point slips
- A candle argument or "wax sample ball", is a thought experiment originally articulated by Ren? Descartes.
Reference
External links
- Candles
Source of the article : Wikipedia
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