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Isophorone Diamine
Isophorone diamine (usually shortened to IPDA) is a diamine with the formula (CH3)3C6H7(NH2)(CH2NH2). It is a colorless liquid. It is a precursor to polymers and coatings. Production It is usually produced as a mixture of the ''cis''- and ''trans''-isomers. It is produced by hydrocyanation of isophorone followed by reductive amination and hydrogenation of the nitrile. Uses IPDA is used as a precursor in the manufacture of isophorone diisocyanate by phosgenation. Like other diamines or amines in general, it is a curing agent for epoxy resins. When used in coatings applications the higher cost compared to other amines is justified by the enhanced UV stability and thus lower yellowing tendency. In the production of Advanced composite materials (engineering) its higher cost compared to other amines is less critical as performance is the key criteria. Cycloaliphatic amines such as IPDA also are known to have lower yellowing tendency than other amines and are thus used in coatings ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamine
A diamine is an amine with exactly two amino groups. Diamines are used as monomers to prepare polyamides, polyimides, and polyureas. The term ''diamine'' refers mostly to primary diamines, as those are the most reactive. In terms of quantities produced, 1,6-diaminohexane (a precursor to Nylon 6-6) is most important, followed by ethylenediamine. Vicinal diamines (1,2-diamines) are a structural motif in many biological compounds and are used as ligands in coordination chemistry. Aliphatic diamines Linear * 1 carbon: methylenediamine (diaminomethane) of theoretical interest only * 2 carbons: ethylenediamine (1,2-diaminoethane). Related derivatives include the N-alkylated compounds, 1,1-dimethylethylenediamine, 1,2-dimethylethylenediamine, ethambutol, tetrakis(dimethylamino)ethylene, TMEDA. File:Ethylene_diamine.png, Ethylenediamine * 3 carbons: 1,3-diaminopropane (propane-1,3-diamine) * 4 carbons: putrescine (butane-1,4-diamine) * 5 carbons: cadaverine (pentane-1,5-diamine) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis–trans Isomerism
''Cis''–''trans'' isomerism, also known as geometric isomerism or configurational isomerism, is a term used in chemistry that concerns the spatial arrangement of atoms within molecules. The prefixes "''cis''" and "''trans''" are from Latin: "this side of" and "the other side of", respectively. In the context of chemistry, ''cis'' indicates that the functional groups (substituents) are on the same side of some plane, while ''trans'' conveys that they are on opposing (transverse) sides. ''Cis''–''trans'' isomers are stereoisomers, that is, pairs of molecules which have the same formula but whose functional groups are in different orientations in three-dimensional space. ''Cis-trans'' notation does not always correspond to E–Z notation, ''E''–''Z'' isomerism, which is an ''Absolute configuration, absolute'' stereochemical description. In general, ''cis''–''trans'' stereoisomers contain double bonds that do not rotate, or they may contain ring structures, where the rotation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocyanation
In organic chemistry, hydrocyanation is a process for conversion of alkenes to nitriles. The reaction involves the addition of hydrogen cyanide and requires a catalyst. This conversion is conducted on an industrial scale for the production of precursors to nylon. Hydrocyanation of unactivated alkenes Industrially, hydrocyanation is commonly performed on alkenes catalyzed by nickel complexes of phosphite () ligands. A general reaction is shown:Piet W.N.M. van Leeuwen "Homogeneous Catalysis: Understanding the Art", 2004, Wiley-VCH, Weinheim. :RCH=CH2 + HCN -> RCH2-CH2-CN Stoichiometry and mechanism The reaction involves the addition of and cyanide () to the substrate. Usually the substrate is an alkene and the product is a nitrile. The reaction proceeds via the oxidative addition of HCN to a low-valent metal complex to give a hydrido cyanide complex. Subsequent binding of the alkene gives the intermediate , which then undergoes migratory insertion to give an alkylmetal cya ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isophorone
Isophorone is an Alpha-beta Unsaturated carbonyl compounds, α,β-unsaturated cyclic ketone. It is a colorless liquid with a characteristic peppermint-like odor, although commercial samples can appear yellowish. Used as a solvent and as a precursor to polymers, it is produced on a large scale industrially. Structure and reactivity Isophorone undergoes reactions characteristic of an α,β-unsaturated ketone. Hydrogenation gives the cyclohexanone derivative. Epoxidation with basic hydrogen peroxide affords the oxide. Isophorone is degraded by attack of hydroxyl radicals. Photodimerization When exposed to sunlight in aqueous solutions, isophorone undergoes 2+2 photocycloaddition to give three isomeric photodimers (Figure). These "diketomers" are cis-syn-cis, head to tail (HT), cys-anti-cys (HT), and head-head (HH). The formation of HH photodimers is favored over HT photodimers with increasing polarity of the medium. Natural Occurrence Isophorone occurs naturally in cran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isophorone Diisocyanate
Isophorone diisocyanate (IPDI) is an organic compound in the class known as isocyanates. More specifically, it is an aliphatic diisocyanate. It is produced in relatively small quantities, accounting for (with hexamethylene diisocyanate) only 3.4% of the global diisocyanate market in the year 2000.{{cite book , first=David , last=Randall , author2=Lee, Steve , title=The Polyurethanes Book , publisher=Wiley , location=New York , year=2002 , isbn=0-470-85041-8 Aliphatic diisocyanates are used, not in the production of polyurethane foam, but in special applications, such as enamel coatings which are resistant to abrasion and degradation from ultraviolet light. These properties are particularly desirable in, for instance, the exterior paint applied to aircraft. Synthesis IPDI is obtained by phosgenation of isophorone diamine: Chemistry IPDI exists in two stereoisomers, cis and trans. Their reactivities are similar. Each stereoisomer is an unsymmetrical molecule, and thus has ... [...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] |
Advanced Composite Materials (engineering)
In materials science, advanced composite materials (ACMs) are materials that are generally characterized by unusually high strength fibres with unusually high stiffness, or modulus of elasticity characteristics, compared to other materials, while bound together by weaker matrices. These are termed "advanced composite materials" in comparison to the composite materials commonly in use such as reinforced concrete, or even concrete itself. The high strength fibers are also low density while occupying a large fraction of the volume. Advanced composites exhibit desirable physical and chemical properties that include light weight coupled with high stiffness ( elasticity), and strength along the direction of the reinforcing fiber, dimensional stability, temperature and chemical resistance, flex performance, and relatively easy processing. Advanced composites are replacing metal components in many uses, particularly in the aerospace industry. Composites are classified according to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,3-BAC
1,3-BAC (1,3-bis(aminomethyl)cyclohexane) is an organic molecule belonging to the sub class cycloaliphatic amine. It has the CAS Registry Number of 2579-20-6. Its key use is as an epoxy resin curing agent. Manufacture It has been produced commercially as part of a mixture with the 1,4 derivative. The primary route of manufacture is by catalytic hydrogenation of ''m''-xylylenediamine usually called MXDA. Uses Like most amines it maybe used as an epoxy curing agent. However, the presence of the amino group also means it can be used in polyurethane chemistry by reacting with isocyanates. In this case a polyurea would be produced. It may also be reacted with phosgene (phosgenation) to produce an isocyanate. Safety It is corrosive with a Packing Group I designation. See also * 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 ep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M-Xylylenediamine
''m''-Xylylenediamine is an organic compound with the formula C6H4(CH2NH2)2. A colorless oily liquid, it is produced by hydrogenation of isophthalonitrile. Uses and reactions ''m''-Xylylenediamine (MXDA) is used in a variety of industrial applications including amine based curing agents for epoxy resins which may then be formulated into coatings, adhesives, sealants, and elastomers. ''m''-Xylylenediamine undergoes to Sommelet reaction to give isophthalaldehyde. Hazards Exposure to ''m''-xylylenediamine may occur by inhalation, skin contact, eye exposure, or ingestion. It can cause chemical burns, tissue damage, delayed pulmonary edema, shock, and skin sensitization. Symptoms of inhalation include a burning sensation in the respiratory tract, cough, sore throat, labored breathing, and dyspnea (shortness of breath). It is also flammable and produces toxic fumes when burned. ''m''-Xylylenediamine reacts with acids, acid chlorides, and acid anhydride An acid anhydride is a type of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4,4-Diaminodicyclohexylmethane
4,4'-Diaminodicyclohexylmethane is the name for organic compounds with the formula CH2(C6H10NH2)2. It is classified as a diamine. In the epoxy industry it is often referred to as PACM, short for ''para''-diaminodicyclohexylmethane. It is used as a curing agent for epoxy resins It finds particular use in epoxy flooring. Another use is to produce diisocyanates, which are precursors to polyurethane. The mixture is a colorless solid, but typical samples are yellowish and oily. The compound is produced as a mixture of three isomers by the hydrogenation of methylenedianiline. These isomers are, in decreasing order of their yield from the hydrogenation, trans-trans, cis-trans, and a small amount of cis-cis. Uses This diamine is mainly used to make epoxy resin curing agents for CASE (Coatings, Adhesives, Sealants, and Elastomers) applications especially flooring. Another application arises from its reaction with phosgene to produce a cycloaliphatic diisocyanate Hydrogenated ... [...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] |
