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Metallic Soap
A metallic soap is a metallic salt of a fatty acid. Theoretically, soaps can be made of any metal, although not all enjoy practical uses. Varying the metal can strongly affect the properties of the compound, particularly its solubility. Alkali, alkaline earth soaps Alkali metal and alkaline earth soaps are white solids. The most commonly encountered are traditional household soaps, which are the fatty acid salts of sodium (hard soap) and potassium (soft soap). Lithium soap or greases, such as lithium stearate, are insoluble in water and find use in lubricating grease. Calcium and magnesium soaps are most commonly encountered as soap scum but the pure materials have a variety of uses. Magnesium stearate and calcium stearate are used as excipients, lubricants, release agents, and food additives, with the later use being covered by the generic E numbers of E470b and E470 respectively. Other metal soaps Aluminium soaps are used as thickening agents, in the production of c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal
A metal () is a material that, when polished or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. These properties are all associated with having electrons available at the Fermi level, as against nonmetallic materials which do not. Metals are typically ductile (can be drawn into a wire) and malleable (can be shaped via hammering or pressing). A metal may be a chemical element such as iron; an alloy such as stainless steel; or a molecular compound such as polythiazyl, polymeric sulfur nitride. The general science of metals is called metallurgy, a subtopic of materials science; aspects of the electronic and thermal properties are also within the scope of condensed matter physics and solid-state chemistry, it is a multidisciplinary topic. In colloquial use materials such as steel alloys are referred to as metals, while others such as polymers, wood or ceramics are nonmetallic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Food Additive
Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives, such as vinegar ( pickling), salt ( salting), smoke ( smoking) and sugar ( crystallization), have been used for centuries to preserve food. This allows for longer-lasting foods, such as bacon, sweets, and wines. With the advent of ultra-processed foods in the late 20th century, many additives having both natural and artificial origin were introduced. Food additives also include substances that may be introduced to food indirectly (called "indirect additives") in the manufacturing process through packaging, storage or transport. In Europe and internationally, many additives are designated with E numbers, while in the United States, additives in amounts deemed safe for human consumption are designated as GRAS. Identification To regulate these additives and inform consumers each additive is assigned a unique number called an "E number", whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saponification
Saponification is a process of cleaving esters into carboxylate salts and Alcohol (chemistry), alcohols by the action of aqueous alkali. Typically aqueous sodium hydroxide solutions are used. It is an important type of alkaline hydrolysis. When the carboxylate is long chain, its salt is called a soap. The saponification of ethyl acetate gives sodium acetate and ethanol: : Saponification of fats Vegetable oils and animal fats are the traditional materials that are saponified. These greasy materials, triesters called triglycerides, are usually mixtures derived from diverse fatty acids. In the traditional saponification, the triglyceride is treated with lye, which cleaves the ester bonds, releasing fatty acid salts (soaps) and glycerol. In one simplified version, the saponification of stearin gives sodium stearate. : This process is the main industrial method for producing glycerol (). Some soap-makers leave the glycerol in the soap. Others precipitation (chemistry), precipitate t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil-based Paint
Oil paint is a type of slow-drying paint that consists of particles of pigment suspended in a drying oil, commonly linseed oil. Oil paint also has practical advantages over other paints, mainly because it is waterproof. The earliest surviving examples of oil paint have been found in Asia from as early as the 7th century AD, in examples of Buddhist paintings in Afghanistan. Oil-based paints made their way to Europe by the 12th century and were used for simple decoration, mostly on wood. Common modern applications of oil paint are in finishing and protection of wood in buildings and exposed metal structures such as ships and bridges. Its hard-wearing properties and luminous colors make it desirable for both interior and exterior use on wood and metal. Due to its slow-drying properties, it has recently been used in paint-on-glass animation. The thickness of the coat has considerable bearing on the time required for drying: thin coats of oil paint dry relatively quickly. The visco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crosslink
In chemistry and biology, a cross-link is a bond or a short sequence of bonds that links one polymer chain to another. These links may take the form of covalent bonds or ionic bonds and the polymers can be either synthetic polymers or natural polymers (such as proteins). In polymer chemistry "cross-linking" usually refers to the use of cross-links to promote a change in the polymers' physical properties. When "crosslinking" is used in the biological field, it refers to the use of a probe to link proteins together to check for protein–protein interactions, as well as other creative cross-linking methodologies. Although the term is used to refer to the "linking of polymer chains" for both sciences, the extent of crosslinking and specificities of the crosslinking agents vary greatly. Synthetic polymers : 260px, left, Chemical reactions associated with crosslinking of drying oils, the process that produces curing'' refers to the crosslinking of thermosetting">linoleum. Cros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil Drying Agent
An oil drying agent, also known as siccative, is a coordination compound that accelerates ( catalyzes) the hardening of drying oils, often as they are used in oil-based paints. This so-called "drying" (actually a chemical reaction that produces an organic plastic) occurs through free-radical chemical crosslinking of the oils. The catalysts promote this free-radical autoxidation of the oils with air. Typical oil drying agents are derived from ions of cobalt, manganese, and iron, prepared as "salts" of lipophilic carboxylic acids such as naphthenic acids, in order to give them a soap-like chemical formula and make them oil-soluble. Varieties of drying agents In technical literature, oil drying agents, such as naphthenates, are described as salts, but they are probably also non-ionic coordination complexes with structures similar to basic zinc acetate. These catalysts were traditionally hydrocarbon carboxylate chelates of lead, but due to lead's toxicity, cobalt and other e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese
Manganese is a chemical element; it has Symbol (chemistry), symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese was first isolated in the 1770s. It is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels. It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent, as a rubber additive, and in glass making, fertilisers, and ceramics. Manganese sulfate can be used as a fungicide. Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. It is found mostly in the bones, but also the liver, kidneys, and brain. In the human brain, the manganese is bound to manganese metalloproteins, most notably glutamine synthetase in astrocytes. Manganese is commonly found in labo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobalt
Cobalt is a chemical element; it has Symbol (chemistry), symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, somewhat brittle, gray metal. Cobalt-based blue pigments (cobalt blue) have been used since antiquity for jewelry and paints, and to impart a distinctive blue tint to glass. The color was long thought to be due to the metal bismuth. Miners had long used the name ''kobold ore'' (German language, German for ''goblin ore'') for some of the blue pigment-producing minerals. They were so named because they were poor in known metals and gave off poisonous arsenic-containing fumes when smelted. In 1735, such ores were found to be reducible to a new metal (the first discovered since ancient times), which was ultimately named for the ''kobold''. Today, some cobalt is produced sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's outer and inner core. It is the fourth most abundant element in the Earth's crust, being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or furnaces capable of reaching , about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, due to their mechan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyvinyl Chloride
Polyvinyl chloride (alternatively: poly(vinyl chloride), colloquial: vinyl or polyvinyl; abbreviated: PVC) is the world's third-most widely produced synthetic polymer of plastic (after polyethylene and polypropylene). About 40 million tons of PVC are produced each year. PVC comes in rigid (sometimes abbreviated as RPVC) and flexible forms. Rigid PVC is used in construction for pipes, doors and windows. It is also used in making plastic bottles, packaging, and bank or membership cards. Adding plasticizers makes PVC softer and more flexible. It is used in plumbing, electrical cable insulation, flooring, signage, phonograph records, inflatable products, and in rubber substitutes. With cotton or linen, it is used in the production of canvas. Polyvinyl chloride is a white, brittle solid. It is soluble in ketones, chlorinated solvents, dimethylformamide, THF and DMAc. Discovery PVC was synthesized in 1872 by German chemist Eugen Baumann after extended investigation and experimenta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thickening Agent
A thickening agent or thickener is a substance which can increase the viscosity of a liquid without substantially changing its other properties. Edible thickeners are commonly used to thicken sauces, soups, and puddings without altering their taste; thickeners are also used in paints, inks, explosives, and cosmetics. Thickeners may also improve the suspension of other ingredients or emulsions which increases the stability of the product. Thickening agents are often regulated as food additives and as cosmetics and personal hygiene product ingredients. Some thickening agents are gelling agents (gellants), forming a gel, dissolving in the liquid phase as a colloid mixture that forms a weakly cohesive internal structure. Others act as mechanical thixotropic additives with discrete particles adhering or interlocking to resist strain. Thickening agents can also be used when a medical condition such as dysphagia causes difficulty in swallowing. Some of these people may benefit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
