Neopentyl glycol diglycidyl ether (NPGDGE) is an organic chemical in the glycidyl ether family. It is aliphatic and a colorless liquid. It has the formula C₁₁H₂₀O₄ and the CAS registry number of 17557-23-2. It has two oxirane groups per molecule. Its principle use is in modifying

epoxy Epoxy is the family of basic components or Curing (chemistry), cured end products of epoxy Resin, resins. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. The epoxide fun ...

resins. It is REACH registered. The IUPAC name is 2- 2,2-dimethyl-3-(oxiran-2-ylmethoxy)propoxyethyl]oxirane.

Synthesis

Neopentyl glycol Neopentyl glycol (IUPAC name: 2,2-dimethylpropane-1,3-diol) is an organic chemical compound. It is used in the synthesis of polyesters, paints, lubricants, and plasticizers. When used in the manufacture of polyesters, it enhances the stability of ...

and

epichlorohydrin 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 miscibility, miscible with most p ...

are reacted in the presence of a

Lewis acid A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any ...

catalyst Catalysis () is the increase in rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quick ...

to form a

halohydrin In organic chemistry a halohydrin (also a haloalcohol or β-halo alcohol) is a functional group in which a halogen and a hydroxyl are bonded to adjacent carbon atoms, which otherwise bear only hydrogen or hydrocarbyl groups (e.g. 2-chloroethanol ...

. This is followed by washing with

sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula . It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly corrosive base (chemistry), ...

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 halide ...

step. This forms Neopentyl glycol diglycidyl ether. The waste products are water and sodium chloride and excess caustic soda. One of the quality control tests would involve measuring the

Epoxy value Epoxy value derives from the Epoxy equivalent weight (EEW) or Weight Per Epoxide (WPE) and is a measure of the epoxy content of an epoxy resin or epoxy reactive diluent, or glycidyl ether. This is an important parameter as it allows determination ...

by determination of the epoxy equivalent weight.

Uses

A key use is modifying the viscosity and properties of epoxy resins. As an

Epoxy Epoxy is the family of basic components or Curing (chemistry), cured end products of epoxy Resin, resins. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. The epoxide fun ...

modifier it is classed as an epoxy

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 ...

. which may then be formulated into CASE applications:

Coating A coating is a covering that is applied to the surface of an object, or 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 ...

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 advantage ...

Sealant Sealant is a substance used to block the passage of fluids through openings in materials, a type of Seal (mechanical), mechanical seal. In building construction ''sealant'' is sometimes synonymous with ''caulk'' (especially if acrylic latex or ...

s and

Elastomer An elastomer is a polymer with viscoelasticity (i.e. both viscosity and elasticity) and with weak intermolecular forces, generally low Young's modulus (E) and high failure strain compared with other materials. The term, a portmanteau of ''ela ...

s and

composite material A composite or composite material (also composition material) 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 ...

s. These uses include cationic polymerization reactions. The use of the diluent does effect mechanical properties and microstructure of epoxy resins. It is also used to synthesize other molecules.

Toxicity

NPGDGE toxicity is fairly well understood. It is classed as a skin irritant and skin sensitizer.

References

External links

Hexion difunctional epoxy diluents

Denacol epoxy diluent range

Aalchem NPGDGE

Cargill Reactive diluents
{{Glycidyl ethers Glycidyl ethers Reactive diluents

Synthesis

Uses

Toxicity

See also

References

Further reading

External links