Epoxy adhesives Glycidyl

Reactive diluents can be used to reduce the modulus and increase the elongation of the cured waterborne epoxy formulations just as they are often used for 100 percent solids and solvent-borne epoxy adhesives. The reactive diluents become codispersed in the formulation with mechanical and chemical stability similar to that of the base epoxy emulsion. Polyglycidyl ether of caster oil, phenyl glycidyl ether, and diglycidyl ether of neophenyl glycol are examples of mono- and difunctional reactive diluents that have been used to improve flexibility and increase the tack-free time of waterborne epoxy adhesives. 

Epoxy adhesives are widely used in electronics assembly and packaging. They are formed by polymerizing epoxy resins having one or more terminal glycidyl ether (epoxy) groups with a variety of curing agents, hardeners, or catalysts. 

Polynuclear Phenol—Glycidyl Ether-Derived Resins. This is one of the first commercially available polyfunctional products. Its polyfunctionahty permits upgrading of thermal stabiUty, chemical resistance, and electrical and mechanical properties of bisphenol A—epoxy systems. It is used in mol ding compounds and adhesives. 

Epoxy resin adhesives from lignin were reported by Tai et al. (19,20) in 1967. Satisfactory gluability was found. The solubility in organic solvents, however, was found to be poor. In essence, the phenolic hydroxyl groups of kraft lignin were glycidylated directly. 

We have also made an attempt to prepare lignin-epoxy resin adhesives (21). However, in order to improve its reactivity, kraft lignin was first phenolated with bisphenol-A. For phenolation, a small amount of aqueous hydrochloric acid or BF3-ethyl etherate was used as catalyst, and thus two kinds of glycidylation methods were adopted (21). The phenolation with bisphenol-A was found to enhance the solubility of the lignin derivative. In fact, the lignin-epoxy resins obtained were found to be completely soluble in certain organic solvents, including acetone. 

In blends of PTT and ABS, two separate glass transition temperatures are observed, which indicates that the blends are phase separated in the amorphous phase. A styrene/butadiene/maleic anhydride copolymer or glycidyl endcapped epoxy resin may act as a compatibilizer. Compatibilized PTT/ABS blends show a finer morphology and better adhesion between the phases. 

The interfacial adhesion between dispersed particles and the matrix can be improved by functionalizing the core-shell particles with any chemical group that can react with the thermosetting polymer. For example, glycidyl methacrylate can be introduced in the shell composition to incorporate functional groups that can react with epoxy formulations. 

Glycidyl amine epoxy resins are reaction products of aromatic amines and epichlorohy-drin. They have high modulus and high glass transition temperature. These resins find use in aerospace composites and high-temperature adhesive formulations. 

In adhesive formulations, aliphatic amines are most commonly used to cure the DGEBA type of epoxy resin. Aliphatic amines are not widely used with the non-glycidyl ether resins, since the amine-epoxy reaction is slow at low temperatures. The reaction usually requires heat and accelerators for an acceptable rate of cure. Aliphatic amines are primarily used with lower-viscosity DGEBA resins because of the difficulty in mixing such low-viscosity curing agents with the more viscous epoxy resins. 

Monofunctional epoxy diluents are used primarily with DGEBA epoxy blends. The most common monofunctional diluents are butyl glycidyl ether and phenyl glycidyl ether. The effect of butyl glycidyl ether and other reactive diluents on the viscosity of epoxy resin is shown in Fig. 6.3. Because the monofunctional diluents reduce crosslink density, they are used at relatively low levels to avoid degrading heat and chemical resistance or other properties of the adhesive. 

Various aliphatic and aromatic mono-glycidyl ethers are available that can be used as reactive diluents of many formulated epoxy structural adhesives. They are... 

Epichlorohydrin is usually prepared from propene and is mainly used in the manufacture of glycerol and epoxy resins. It is also used in the manufacture of elastomers, glycidyl ethers, cross-linked food starch, surfactants, plasticizers, dyestuffs, pharmaceutical products, oil emulsifiers, lubricants, and adhesives as a solvent for resins, gums, cellulose, esters, paints, and lacquers and as a stabilizer in chlorine-containing substances such as rubber, pesticide formulations, and solvents. 

Cardura E 10 CCRIS 2627 EINECS 247-979-2 2,3-Epoxypropyl neodecanoate Glycidyl ester of neodeoanoic acid Glycidyl neodecanoate Glydexx N 10 Neodecanoic acid, 2,3-epoxypropyl ester Neodecanoic acid, oxiranylmethyi ester 1-Propanoi, 2,3-epoxy-, neodecanoate. Polyfunctional monomer in coatings to improve adhesion to substrate and solvent resistance. Liquid bp = 260° d = 0,97 insoluble in H2O, soluble in organic solvents LDso (rat orl) > 9,59 g/kg, ExxonMobil Chem. Co. 

MAJOR USES Used in the manufacture of epoxy resins, glycerol, pharmaceuticals, agricultural chemicals, coatings, ion excheinge resins glycidyl esters insecticides textile chemicals adhesives plasticizers solvent for natural and synthetic resins, gums, cellulose esters and ethers, paints, varnishes and nail enamels and lacquers stabilizer in chlorine containing materials and an intermediate in the preparation of condensates with polyfiinctional substances. 

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