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Epichlorhydrin
Epichlorohydrin (abbreviated ECH) is an organochlorine compound and an epoxide. Despite its name, it is not a halohydrin. It is a colorless liquid with a pungent, garlic-like odor, moderately soluble in water, but miscible with most polar organic solvents. It is a chiral molecule generally existing as a racemic mixture of right-handed and left-handed enantiomers. Epichlorohydrin is a highly reactive electrophilic compound and is used in the production of glycerol, plastics, epoxy glues and resins, epoxy diluents and elastomers. Production Epichlorohydrin is traditionally manufactured from allyl chloride in two steps, beginning with the addition of hypochlorous acid, which affords a mixture of two isomeric alcohols: : In the second step, this mixture is treated with base to give the epoxide: : In this way, more than 800,000 tons (1997) of epichlorohydrin are produced annually. Glycerol routes Epichlorohydrin was first described in 1848 by Marcellin Berthelot. The compound ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biodiesel
Biodiesel is a form of diesel fuel derived from plants or animals and consisting of long-chain fatty acid esters. It is typically made by chemically reacting lipids such as animal fat ( tallow), soybean oil, or some other vegetable oil with an alcohol, producing a methyl, ethyl or propyl ester by the process of transesterification. Unlike the vegetable and waste oils used to fuel converted diesel engines, biodiesel is a drop-in biofuel, meaning it is compatible with existing diesel engines and distribution infrastructure. However, it is usually blended with petrodiesel (typically to less than 10%) since most engines cannot run on pure Biodiesel without modification. Biodiesel blends can also be used as heating oil. The US National Biodiesel Board defines "biodiesel" as a mono-alkyl ester. Blends Blends of biodiesel and conventional hydrocarbon-based diesel are most commonly distributed for use in the retail diesel fuel marketplace. Much of the world uses a syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Isomer
In chemistry, a structural isomer (or constitutional isomer in the IUPAC nomenclature) of a compound is another compound whose molecule has the same number of atoms of each element, but with logically distinct bonds between them. The term metamer was formerly used for the same concept. For example, butanol , methyl propyl ether , and diethyl ether have the same molecular formula but are three distinct structural isomers. The concept applies also to polyatomic ions with the same total charge. A classical example is the cyanate ion and the fulminate ion . It is also extended to ionic compounds, so that (for example) ammonium cyanate and urea are considered structural isomers,William F. Bynum, E. Janet Browne, Roy Porter (2014): ''Dictionary of the History of Science''. 530 pages. and so are methylammonium formate and ammonium acetate . Structural isomerism is the most radical type of isomerism. It is opposed to stereoisomerism, in which the atoms and bonding s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epoxy Resin
Epoxy is the family of basic components or cured end products of epoxy resins. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. The epoxide functional group is also collectively called ''epoxy''. The IUPAC name for an epoxide group is an oxirane. Epoxy resins may be reacted ( cross-linked) either with themselves through catalytic homopolymerisation, or with a wide range of co-reactants including polyfunctional amines, acids (and acid anhydrides), phenols, alcohols and thiols (usually called mercaptans). These co-reactants are often referred to as hardeners or curatives, and the cross-linking reaction is commonly referred to as curing. Reaction of polyepoxides with themselves or with polyfunctional hardeners forms a thermosetting polymer, often with favorable mechanical properties and high thermal and chemical resistance. Epoxy has a wide range of applications, including metal coatings, composites, u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bisphenol A Diglycidyl Ether
Bisphenol A diglycidyl ether (commonly abbreviated BADGE or DGEBA) is an organic compound used as constituent of epoxy resins. The compound is a colorless solid (commercial samples can appear yellow) that melts slightly above room temperature. Preparation and reactions It is prepared by O-alkylation of bisphenol A with epichlorohydrin. This reaction mainly affords bisphenol A diglycidyl ether, as well as some oligomer. The degree of polymerization may be as low as 0.1. The epoxide content of such epoxy resins is of interest. This parameter is commonly expressed as the epoxide number, which is the number of epoxide equivalents in 1 kg of resin (Eq./kg), or as the equivalent weight, which is the weight in grams of resin containing 1 mole equivalent of epoxide (g/mol). Since unsymmetrical epoxides are chiral, the bis epoxide consists of three stereoisomers, although these are not separated. Bisphenol A diglycidyl ether slowly hydrolyzes to 2,2-bis left, 352px, vinyl_e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epoxidation
In organic chemistry, an epoxide is a cyclic ether () with a three-atom ring. This ring approximates an equilateral triangle, which makes it strained, and hence highly reactive, more so than other ethers. They are produced on a large scale for many applications. In general, low molecular weight epoxides are colourless and nonpolar, and often volatile. Nomenclature A compound containing the epoxide functional group can be called an epoxy, epoxide, oxirane, and ethoxyline. Simple epoxides are often referred to as oxides. Thus, the epoxide of ethylene (C2H4) is ethylene oxide (C2H4O). Many compounds have trivial names; for instance, ethylene oxide is called "oxirane". Some names emphasize the presence of the epoxide functional group, as in the compound ''1,2-epoxyheptane'', which can also be called ''1,2-heptene oxide''. A polymer formed from epoxide precursors is called an ''epoxy'', but such materials do not contain epoxide groups (or contain only a few residual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalyst
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxylic Acid
In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids. Deprotonation of a carboxylic acid gives a carboxylate anion. Examples and nomenclature Carboxylic acids are commonly identified by their trivial names. They at oftentimes have the suffix ''-ic acid''. IUPAC-recommended names also exist; in this system, carboxylic acids have an ''-oic acid'' suffix. For example, butyric acid (C3H7CO2H) is butanoic acid by IUPAC guidelines. For nomenclature of complex molecules containing a carboxylic acid, the carboxyl can be considered position one of the parent chain even if there are other substituents, such as 3-chloropropanoic acid. Alternately, it can be named as a "carboxy" or "carboxylic acid" substituent on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substitution Reaction
A substitution reaction (also known as single displacement reaction or single substitution reaction) is a chemical reaction during which one functional group in a chemical compound is replaced by another functional group. Substitution reactions are of prime importance in organic chemistry. Substitution reactions in organic chemistry are classified either as electrophilic or nucleophilic depending upon the reagent involved, whether a reactive intermediate involved in the reaction is a carbocation, a carbanion or a free radical, and whether the substrate is aliphatic or aromatic. Detailed understanding of a reaction type helps to predict the product outcome in a reaction. It also is helpful for optimizing a reaction with regard to variables such as temperature and choice of solvent. A good example of a substitution reaction is halogenation. When chlorine gas (Cl2) is irradiated, some of the molecules are split into two chlorine radicals (Cl•), whose free electrons are strongl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dow Chemical
The Dow Chemical Company, officially Dow Inc., is an American multinational corporation, multinational chemical corporation headquartered in Midland, Michigan, United States. The company is among the three List of largest chemical producers, largest chemical producers in the world. Dow manufactures plastics, chemicals, and agricultural products. With a presence in about 160 countries, it employs about 54,000 people worldwide. Dow has been called the "chemical companies' chemical company," as its sales are to other industries rather than directly to end-use consumers. Dow is a member of the American Chemistry Council. In 2015, Dow and fellow chemical company DuPont agreed to a corporate reorganization which involved the merger and split of Dow and DuPont into three different companies. The plan commenced in 2017, when Dow and DuPont merged to form DowDuPont, and finalized in April 2019, as the materials science division was spunoff from DowDuPont and took the name of the Dow Chemica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biofuel
Biofuel is a fuel that is produced over a short time span from biomass, rather than by the very slow natural processes involved in the formation of fossil fuels, such as oil. According to the United States Energy Information Administration (EIA), biofuels are mostly used for transportation, but can also be used for heating and electricity. Biofuel can be produced from plants or from agricultural, domestic or industrial biowaste. The greenhouse gas mitigation potential of biofuel varies considerably, from emission levels comparable to fossil fuels in some scenarios to negative emissions in others. See the biomass article for more on this particular subject. The two most common types of biofuel are Ethanol#Fuel, bioethanol and biodiesel. The U.S. is the largest producer of bioethanol, while the EU is the largest producer of biodiesel. The energy content in the global production of bioethanol and biodiesel is 2.2 and 1.8 EJ per year, respectively. * Bioethanol is an Alcohol (chem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Chloride
The compound hydrogen chloride has the chemical formula and as such is a hydrogen halide. At room temperature, it is a colourless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hydrogen chloride gas and hydrochloric acid are important in technology and industry. Hydrochloric acid, the aqueous solution of hydrogen chloride, is also commonly given the formula HCl. Reactions Hydrogen chloride is a diatomic molecule, consisting of a hydrogen atom H and a chlorine atom Cl connected by a polar covalent bond. The chlorine atom is much more electronegative than the hydrogen atom, which makes this bond polar. Consequently, the molecule has a large dipole moment with a negative partial charge (δ−) at the chlorine atom and a positive partial charge (δ+) at the hydrogen atom. In part because of its high polarity, HCl is very soluble in water (and in other polar solvents). Upon contact, and HCl combine to form hydronium cations a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
