During epoxy floor construction, a small number of epoxy resin floor paint products must add solvents , the following will introduce to you how to choose the commonly used solvents for epoxy floor paint coatings. Epoxy resin can be dissolved in certain organic solvents, and the solubility of the resin decreases as the molecular weight increases. Ketones, vinegars, ether alcohols and chlorinated hydrocarbons are solvents for epoxy resin and have good dissolving ability for epoxy resin. Aromatic hydrocarbons and alcohols are not solvents for epoxy resins, but when mixed with aromatic hydrocarbons and alcohols, they can be used as solvents for medium molecular weight resins.
Solvents are divided by reactivity, including inactive solvents and active solvents. Inactive solvents cannot chemically react with epoxy resins and curing agents. They only play a physical dissolving role in the composition of epoxy resins; while active solvents contain one or more epoxy groups in the molecular structure of their compounds. , can react chemically with the curing agent and cure together with the epoxy resin.
Inactive solvents are added to reduce the strength of the epoxy resin components and meet construction requirements. , they will eventually evaporate from the cured product, so their selection must not only be based on solubility and solvent evaporation speed, but also cost and toxicity. Although inactive solvents have the advantages of having many varieties, wide sources, and low prices, they are not conducive to environmental protection. Nowadays, people have increasingly stricter control over the content of volatile organic compounds (VOC), and they are required to use as little or no inactive solvents as possible. Therefore, reactive solvents that are low in volatility and can participate in curing reactions have attracted more and more attention.
The solvents used in epoxy resin floor paint are mixed solvents, which are composed of solvents and diluents. There are many advantages to using mixed solvents, such as reducing costs, improving paint film performance and construction performance, and increasing the solubility of solvents. The following introduces the issues that should be paid attention to when preparing mixed solvents:
(1) Solvents with high solubility and molecular weight The resin should use ketones or ether alcohols as solvents; medium molecular weight resins can use a mixture of aromatic hydrocarbons and alcohols as solvents; low molecular weight resins can be soluble in aromatic hydrocarbons, but in order to improve the solubility, mixed solvents of aromatic hydrocarbons and alcohols are often used.
(2) Paint construction method The mixed solvent used in the paint construction, the initial evaporation speed should be Slower to achieve the purpose of saving effort during brushing and fully leveling the brush marks on the paint film. The initial evaporation rate of the mixed solvent used in drying paint should also be controlled to prevent the paint film from becoming morbid due to the solvent evaporating too quickly.
(3) Reactivity of solvents As mentioned earlier, active solvents such as vinegar or ketones can react with amines Reaction will reduce the curing effect of the amine.
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