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Epoxides react by the opening of the carbon-carbon-oxygen ring. This produces 2 reactive sites per epoxide group. This is illustrated by the reaction of hydrochloric acid within an epoxide group.

Epoxidized vegetable oils can also be reacted through their 3 esters groups. For example, Epoxol® 9-5 -Epoxidized Linseed Oil contains approximately 12 epoxide reaction sites and 3 ester sites for a theoretical total of 15 reactive sites per molecule.


The epoxide group can react with all types of acids (mineral, halogenic and carboxylic acids) forming neutral compounds. This reaction makes epoxides effective and efficient acid scavengers.


The reaction of an Epoxides with a diol or polyol, catalyzed by a Lewis acid, will result in the formation of a polyether. Since Epoxol® 9-5 -Epoxidized Linseed Oil has multiple oxirane units, its use in polyether systems increases the degree of crosslinking.

Polyols / Hydroxyl

The reaction of Epoxides with hydroxyl containing materials is a general one. When a monoalcohol is used, the oxirane ring opens to form a vicinal hydroxyether. By using a large excess of alcohol, it is possible to make a polyol from the Epoxides containing as much hydroxyl functionality as there was epoxy functionality in the original Epoxides. Thus, if Epoxol® 9-5 is slowly added to a solution of BF
3 etherate in a large amount of methyl alcohol, the resulting product, after the excess methanol is stripped off, will be a polyol containing about 5 1/2 hydroxyl groups per molecule. This can be used as a reactive monomer, or it can be ethoxylated to make the hydroxyl groups primary for use in urethane polymerization.
Curing of Epoxides with Polyamines

Epoxides can be cured to a rough resin with good flexibility by baking with reactive polyamines, such as tetraethylene pentamine. The reaction rates of Epoxides are considerably slower toward alkaline reagents than are the glycidyl ethers and curing without baking is not feasible.

Normal curing cycles on such systems would include prereactions of the Epoxides  and the polyamine for an hour at not over 100
ºC, and a final cure at up to 16 hours at 150ºC.
Ester Interchange

The Epoxides will undergo ester interchange with reactive alcohols while retaining their oxirane functionality. The reaction is catalyzed by base and is usually done with catalytic amounts of the sodium or potassium salt of the alcohol to be exchanged, or with sodium methoxide or potassium t-butoxide. A large excess of alcohol is necessary, making it both reactant and solvent. Ester interchange is a tool to build additional functionality or reactive centers into a polyepoxide molecule.
Polymer Reactions

Polyesters may be formed by gently warming and mixing stoichiometric amounts of an organic dicarboxylic acid or anhydride with an Epoxides until an exothermic reaction is initiated. The heat necessary to initiate the reaction depends upon the reactivity of the acid or anhydride employed, but generally the acids react more vigorously and at lower temperatures than anhydrides. Both reactions are generally catalyzed by a tertiary amine or a tertiary phosphine.

Epoxy Resins

In some formulas Epoxides are compatible with the Bisphenol A epoxies or the cycloaliphatic epoxies typically used in epoxy resins and castings. Actually, 20% to 40% of these standard epoxy materials can be replaced by Epoxol in order to reduce cost and viscosity of the resin system without materially affecting tensile  strength, hardness or Gahimer temperature/humidity test results. At the same time, electrical properties, heat weight loss, and water absorption characteristics are maintained while thermal shock resistance is improved.

Non Crosslinked Esters

Vicinal hydroxy esters can be prepared by the reaction of organic acids and Epoxols. When monobasic acids are used, non-crosslinked esters are formed at some, or all, of the reactive oxirane groups. The amount of reaction can be controlled by the stoichiometry of the acid to oxirane groups. When a functionally reactive acid, such as acrylic or methacrylic, is used, the resulting esters can be reactive oligomers that will undergo further polymerization reactions in U.V. cured inks and coatings, as comonomers with vinyl-chloride or vinyl acetate, or in anerobic adhesive applications.