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The hydroxyl value means the number of moles of hydroxyl groups contained in 100 g of the epoxy resin. The hydroxyl equivalent refers to the mass of epoxy resin containing 1mol hydroxyl grams. Hydroxyl wood plastic lumber lowes determination of two ways: First, direct determination of hydroxyl content in the epoxy resin; the second is to open the epoxy group to form a hydroxyl group, and further determination of the sum of the hydroxyl content. The former method is based on lithium aluminum hydride and active hydrogen-containing groups for rapid and quantitative reaction principle, for the direct determination of epoxy resin hydroxyl, is a more reliable method.
The latter method is acetic anhydride, pyridine and concentrated sulfuric acid mixture of acetylation reagents and epoxy resin reaction to form a hydroxyl group, and then determine the total hydroxyl content, and then double the epoxy reduced, you can measure the ring The hydroxyl content in Rotational Molding Plastic Fence Panels the oxygen resin is the hydroxyl number. Esterification equivalents: Esterification equivalents refer to the mass grams of epoxy resin needed to esterify 1 mole of monocarboxylic acid (60 g of acetic acid or 280 g of C18 fatty acid). Epoxy hydroxyl and epoxy groups can be esterified with carboxylic acid.
Esterification equivalents may represent the total content of hydroxyl and epoxy groups in the resin. Inorganic chlorine mainly refers to the chloride ion in the resin. The presence of inorganic chlorine affects the electrical properties of the cured resin. The organochlorine Remove Plasticizer Migration from Wood Table content in the resin indicates the content of the part of the chlorohydrin group in the molecule that does not close the ring-closed reaction, and its content should be reduced as much as possible.
Otherwise, the curing of the resin and the properties of the cured product will be affected. Viscosity: The viscosity of epoxy resin epoxy resin is one of the important indicators of the actual use. Different temperatures, the viscosity of epoxy resin is different, its flow properties will be different. Viscosity can usually be measured with cup viscometer, rotational interlocking deck boards viscometer, capillary viscometer and falling ball viscometer.