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Oxetane, 3,3-bis(chloromethyl)-
3,3-Bis(chloromethyl)oxetane (BCMO) is a useful monomer in the field of energetic materials for synthesis of poly(bis(azidomethyl)oxetane (PolyBAMO), which is being researched by numerous militaries around the world. Poly-BAMO is an energetic polymer that have potential to replace the current propellant binder formulations. ttp://www.dtic.mil/dtic/tr/fulltext/u2/a377866.pdf It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities. It can cause kidney damage, lacrimation, and somnolence if consumed. Preparation and reaction BCMO is formed in solution via cyclization of pentaerythritol trichlorohydrin with a non-organic base like sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monomer
In chemistry, a monomer ( ; ''mono-'', "one" + '' -mer'', "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization. Classification Monomers can be classified in many ways. They can be subdivided into two broad classes, depending on the kind of the polymer that they form. Monomers that participate in condensation polymerization have a different stoichiometry than monomers that participate in addition polymerization: : Other classifications include: *natural vs synthetic monomers, e.g. glycine vs caprolactam, respectively *polar vs nonpolar monomers, e.g. vinyl acetate vs ethylene, respectively *cyclic vs linear, e.g. ethylene oxide vs ethylene glycol, respectively The polymerization of one kind of monomer gives a homopolymer. Many polymers are copolymers, meaning that they are derived from two different monomers. In the case of condensation polymerizations, the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclic Compound
A cyclic compound (or ring compound) is a term for a compound in the field of chemistry in which one or more series of atoms in the compound is connected to form a ring. Rings may vary in size from three to many atoms, and include examples where all the atoms are carbon (i.e., are carbocycles), none of the atoms are carbon (inorganic cyclic compounds), or where both carbon and non-carbon atoms are present (heterocyclic compounds). Depending on the ring size, the bond order of the individual links between ring atoms, and their arrangements within the rings, carbocyclic and heterocyclic compounds may be aromatic or non-aromatic; in the latter case, they may vary from being fully saturated to having varying numbers of multiple bonds between the ring atoms. Because of the tremendous diversity allowed, in combination, by the valences of common atoms and their ability to form rings, the number of possible cyclic structures, even of small size (e.g., < 17 total atoms) numbers in the many b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase-transfer Catalyst
In chemistry, a phase-transfer catalyst or PTC is a catalyst that facilitates the transition of a reactant from one phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of heterogeneous catalysis. Ionic reactants are often soluble in an aqueous phase but insoluble in an organic phase in the absence of the phase-transfer catalyst. The catalyst functions like a detergent for solubilizing the salts into the organic phase. Phase-transfer catalysis refers to the acceleration of the reaction upon the addition of the phase-transfer catalyst. By using a PTC process, one can achieve faster reactions, obtain higher conversions or yields, make fewer byproducts, eliminate the need for expensive or dangerous solvents that will dissolve all the reactants in one phase, eliminate the need for expensive raw materials and/or minimize waste problems. Phase-transfer catalysts are especially useful in green chemistry—by allowing the use of water, the nee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabutylammonium Bromide
Tetrabutylammonium bromide (TBAB) is a quaternary ammonium salt with a bromide commonly used as a phase transfer catalyst. It is used to prepare many other tetrabutylammonium salts by salt metathesis reactions. The anhydrous form is a white solid. In addition to being cheap, tetrabutylammonium bromide is also environmentally friendly, has a greater degree of selectivity, is operationally simple, non-corrosive, and can be recycled easily as well. Preparation and reactions Tetrabutylammonium bromide can be prepared by the alkylation of tributylamine with 1-bromobutane. Tetrabutylammonium bromide is used to prepare other salts of the tetrabutylammonium cation by salt metathesis reactions., , ;. It serves as a source of bromide ions for substitution reactions. It is one of a commonly-used phase transfer catalyst. As its melting point is just over 100 °C and decreases in the presence of other reagents, it can be considered an ionic liquid. Role in semi-clathrate formation TBAB ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hydroxide
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and may cause severe chemical burns. It is highly soluble in water, and readily absorbs moisture and carbon dioxide from the air. It forms a series of hydrates . The monohydrate crystallizes from water solutions between 12.3 and 61.8 °C. The commercially available "sodium hydroxide" is often this monohydrate, and published data may refer to it instead of the anhydrous compound. As one of the simplest hydroxides, sodium hydroxide is frequently used alongside neutral water and acidic hydrochloric acid to demonstrate the pH scale to chemistry students. Sodium hydroxide is used in many industries: in the manufacture of pulp and paper, textiles, drinking water, soaps and deterge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base (chemistry)
In chemistry, there are three definitions in common use of the word base, known as Arrhenius bases, Brønsted bases, and Lewis bases. All definitions agree that bases are substances that react with acids, as originally proposed by G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form Hydroxide ions OH−. These ions can react with hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction An acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH via titration. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their applica .... A base was therefore a metal hydroxide such as Sodium hydroxide, NaOH or Calcium hydroxide, Ca(OH)2. Such aqueous hydroxide solutions were also described by certain characteristic properties. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentaerythritol Trichlorohydrin
Pentaerythritol is an organic compound with the formula C(CH2OH)4. Classified as a polyol, it is a white solid. Pentaerythritol is a building block for the synthesis and production of explosives, plastics, paints, appliances, cosmetics, and many other commercial products. The word pentaerythritol is a blend of ''penta-'' in reference to its 5 carbon atoms and ''erythritol'', which also possesses 4 alcohol groups. Synthesis Pentaerythritol was first reported in 1891 by German chemist Bernhard Tollens and his student P. Wigand. It may be prepared via a base-catalyzed multiple-addition reaction between acetaldehyde and 3 equivalents of formaldehyde to give pentaerythrose (CAS: 3818-32-4), followed by a Cannizzaro reaction with a fourth equivalent of formaldehyde to give the final product. Uses Pentaerythritol is a versatile building block for the preparation of many compounds, particularly polyfunctionalized derivatives. applications include alkyd resins, varnishes, polyvinyl c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Somnolence
Somnolence (alternatively sleepiness or drowsiness) is a state of strong desire for sleep, or sleeping for unusually long periods (compare hypersomnia). It has distinct meanings and causes. It can refer to the usual state preceding falling asleep, the condition of being in a drowsy state due to circadian rhythm disorders, or a symptom of other health problems. It can be accompanied by lethargy, weakness and lack of mental agility. Somnolence is often viewed as a symptom rather than a disorder by itself. However, the concept of somnolence recurring at certain times for certain reasons constitutes various disorders, such as excessive daytime sleepiness, shift work sleep disorder, and others; and there are medical codes for somnolence as viewed as a disorder. Sleepiness can be dangerous when performing tasks that require constant concentration, such as driving a vehicle. When a person is sufficiently fatigued, microsleeps may be experienced. In individuals deprived of sleep, somno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poly(bis(azidomethyl)oxetane
Poly, from the Greek πολύς meaning "many" or "much", may refer to: Businesses * China Poly Group Corporation, a Chinese business group, and its subsidiaries: ** Poly Property, a Hong Kong incorporated Chinese property developer ** Poly Real Estate, a Chinese real estate developer ** Poly Technologies, a defense manufacturing company * Poly (company), formerly Polycom, an American communications technology company People * Poly (footballer) (1906-1986), full name Policarpo Ribeiro de Oliveira, Brazilian footballer * Natasha Poly (born 1985), stage name of Russian supermodel Natalya Sergeyevna Polevshchikova * Poly Styrene (1957–2011), stage name of British musician Marianne Joan Elliott-Said Other uses * Hong Kong Polytechnic University, locally known as Poly * Poly (website), a website by Google * Polynesian, often shortened to poly, as in ‘Poly people are also called “Pasifika” or “Tangata Moana” (people of the ocean)’ * Polyamory, often shortened to poly, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacrimation
Tears are a clear liquid secreted by the lacrimal glands (tear gland) found in the eyes of all land mammals. Tears are made up of water, electrolytes, proteins, lipids, and mucins that form layers on the surface of eyes. The different types of tears—basal, reflex, and emotional—vary significantly in composition. The functions of tears include lubricating the eyes (basal tears), removing irritants (reflex tears), and also aiding the immune system. Tears also occur as a part of the body's natural pain response. Emotional secretion of tears may serve a biological function by excreting stress-inducing hormones built up through times of emotional distress. Tears have symbolic significance among humans. Physiology Chemical composition Tears are made up of three layers: lipid, aqueous, and mucous. Tears are composed of water, salts, antibodies, and lysozymes (antibacterial enzymes); though composition varies among different tear types. The composition of tears caused by an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
