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1,4-Butanediol Diglycidyl Ether
1,4-Butanediol diglycidyl ether (B14DODGE) is an organic chemical in the glycidyl ether family. It is aliphatic and a colorless liquid. It has two epoxide (oxirane) groups per molecule. Its main use is in modifying epoxy resins especially viscosity reduction. It is REACH registered. The IUPAC name is 2- -(oxiran-2-ylmethoxy)butoxymethylxirane. Synthesis 1,4-Butanediol and epichlorohydrin are reacted in the presence of a Lewis acid as catalyst to form a halohydrin: each hydroxyl group of the diol reacts with an epoxide on epichlorohydrin. This process is followed by washing with sodium hydroxideto re-form the epoxide rings in dehydrochlorination reaction. One of the quality control tests would involve measuring the Epoxy value by determination of the epoxy equivalent weight. Uses A key use is modifying the viscosity and properties of epoxy resins which may then be formulated into CASE applications: Coatings, Adhesives, Sealants, Elastomers, composite materials, fillers, putties, p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycidol
Glycidol is an organic compound that contains both epoxide and alcohol functional groups. Being bifunctional, it has a variety of industrial uses. The compound is a slightly viscous liquid that is slightly unstable and is not often encountered in pure form. Synthesis and applications Glycidol is prepared by the epoxidation of allyl alcohol.Guenter Sienel, Robert Rieth, Kenneth T. Rowbottom "Epoxides" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. Glycidol is used as a stabilizer for natural oils and vinyl polymers and as a demulsifier. It is used as a chemical intermediate in the synthesis of glycerol, glycidyl ethers, esters and amines. It is used in surface coatings, chemical synthesis, pharmaceuticals, sanitary chemicals and sterilizing milk of magnesia, and as a gelation agent in solid propellants. #Alkylation of 2-methylquinazolin-4(3H)-one with glycidol affords diproqualone. #Dyphylline was made by the alkylation of theophylline with glycid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydrochlorination
In chemistry, dehydrohalogenation is an elimination reaction which removes a hydrogen halide from a substrate. The reaction is usually associated with the synthesis of alkenes, but it has wider applications. Dehydrohalogenation from alkyl halides Traditionally, alkyl halides are substrates for dehydrohalogenations. The alkyl halide must be able to form an alkene, thus halides having no C–H bond on an adjacent carbon are not suitable substrates. Aryl halides are also unsuitable. Upon treatment with strong base, chlorobenzene dehydrohalogenates to give phenol via a benzyne intermediate. Base-promoted reactions to alkenes When treated with a strong base many alkyl chlorides convert to corresponding alkene. It is also called a β-elimination reaction and is a type of elimination reaction. Some prototypes are shown below: :\begin \ce\ &\ce \\ \ce\ &\ce \\ \ce\ &\ce \end Here ethyl chloride reacts with potassium hydroxide, typically in a solvent such as ethanol, giving ethylene. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermatitis
Dermatitis is inflammation of the skin, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can vary from small to covering the entire body. Dermatitis is often called eczema, and the difference between those terms is not standardized. The exact cause of the condition is often unclear. Cases may involve a combination of allergy and poor venous return. The type of dermatitis is generally determined by the person's history and the location of the rash. For example, irritant dermatitis often occurs on the hands of those who frequently get them wet. Allergic contact dermatitis occurs upon exposure to an allergen, causing a hypersensitivity reaction in the skin. Prevention of atopic dermatitis is typically with essential fatty acids, and may be treated with moisturizers and steroid creams. The steroid creams should generally be of mid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reactive Diluent
Reactive diluents are substances which reduce the viscosity of a lacquer or resin for processing and become part of the lacquer or coating during its subsequent curing via copolymerization. A non-reactive diluent would be a solvent or plasticizer. Diluents (or thinners) are usually added to lacquers or other resins, to reduce their viscosity and rheology). In thermal cured lacquers, such diluents added are volatile substances which evaporate from the lacquer during drying. In the case of radiation-curing lacquers (for example UV lacquers), those diluents should be avoided. The addition of reactive diluents facilitates the processing of the lacquers, allows the addition of more fillers and improves the wetting behavior on the substrate.Bodo Müller, Walter Rath: Formulierung von Kleb- und Dichtstoffen – das kompetente Lehrbuch für Studium und Praxis. 2. Auflage. Vincentz Network, Hannover 2009, , S. 149–150 If volatile diluents are replaced by reactive diluents, flammabi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epoxy
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, use in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Material
A composite material (also called a composition material or shortened to composite, which is the common name) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions. Typical engineered composite materials include: *Reinforced concrete and masonry *Composite wood such as plywood *Reinforced plastics, such as fibre-reinforced polymer or fiberglass *Ceramic matrix composites ( composite ceramic and metal matrices) *Metal matrix composites *and other advanced composite materials There are various reasons where new material can be favoured. Typical examples include materials which are less expensive, lighter, stronger or more durable when compared with commo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elastomer
An elastomer is a polymer with viscoelasticity (i.e. both viscosity and elasticity) and with weak intermolecular forces, generally low Young's modulus and high failure strain compared with other materials. The term, a portmanteau of ''elastic polymer'', is often used interchangeably with rubber, although the latter is preferred when referring to vulcanisates. Each of the monomers which link to form the polymer is usually a compound of several elements among carbon, hydrogen, oxygen and silicon. Elastomers are amorphous polymers maintained above their glass transition temperature, so that considerable molecular reconformation is feasible without breaking of covalent bonds. At ambient temperatures, such rubbers are thus relatively compliant ( E ≈ 3 M Pa) and deformable. Their primary uses are for seals, adhesives and molded flexible parts. Application areas for different types of rubber are manifold and cover segments as diverse as tires, soles for shoes, and damping and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sealant
Sealant is a substance used to block the passage of fluids through openings in materials, a type of mechanical seal. In building construction ''sealant'' is sometimes synonymous with ''caulking'' and also serve the purposes of blocking dust, sound and heat transmission. Sealants may be weak or strong, flexible or rigid, permanent or temporary. Sealants are not adhesives but some have adhesive qualities and are called ''adhesive-sealants'' or ''structural sealants''. History Sealants were first used in prehistory in the broadest sense as mud, grass and reeds to seal dwellings from the weather such as the daub in wattle and daub and thatching. Natural sealants and adhesive-sealants included plant resins such as pine pitch and birch pitch, bitumen, wax, tar, natural gum, clay (mud) mortar, lime mortar, lead, blood and egg. In the 17th century glazing putty was first used to seal window glass made with linseed oil and chalk, later other drying oils were also used to make oil-bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesive
Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantages over other binding techniques such as sewing, mechanical fastenings, or welding. These include the ability to bind different materials together, the more efficient distribution of stress across a joint, the cost-effectiveness of an easily mechanized process, and greater flexibility in design. Disadvantages of adhesive use include decreased stability at high temperatures, relative weakness in bonding large objects with a small bonding surface area, and greater difficulty in separating objects during testing. Adhesives are typically organized by the method of adhesion followed by ''reactive'' or ''non-reactive'', a term which refers to whether the adhesive chemically reacts in order to harden. Alternatively, they can be organized eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coating
A coating is a covering that is applied to the surface of an object, usually referred to as the Substrate (materials science), substrate. The purpose of applying the coating may be decorative, functional, or both. Coatings may be applied as liquids, gases or solids e.g. Powder coatings. Paints and lacquers are coatings that mostly have dual uses of protecting the substrate and being decorative, although some artists paints are only for decoration, and the paint on large industrial pipes is for preventing corrosion and identification e.g. blue for process water, red for fire-fighting control etc. Functional coatings may be applied to change the surface properties of the substrate, such as adhesion, Wetting, wettability, corrosion resistance, or wear resistance. In other cases, e.g. semiconductor device fabrication (where the substrate is a wafer (electronics), wafer), the coating adds a completely new property, such as a magnetic response or electrical conductivity, and forms an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epoxy Value
Epoxy is the family of basic components or Curing (chemistry), 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, ... [...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] |
