Crystallization
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What is crystallization in epoxy resin? Crystalization by definition refers to the phase change from a liquid to a solid resin. It is similar to water turning from liquid into ice, and vice versa. Like the freeze/thaw cycles of water crystallization of epoxy resin is completely reversible. As water remains unchanged from repeated cycles, so do the original properties of epoxy resin. At the onset of crystallization, the clear resin begins to look foggy, cloudy, hazy or turbid. Since the crystals are higher in density they will tend to sink to the bottom of the container. Liquid epoxy resins are super-cooled liquids that are supposed to be solid at room temperature with a melt point in the 40°-50° C range. Liquid epoxy resins super-cool due to the slow process of crystallization below the melting temperature. Temperature cycles of as little as 20-30°C are the most common cause of crystallization. Resin purity, viscosity, added fillers and temperature extremes can also lead to crystallization problems. Increasing the temperature of epoxy resins above 50°C for a few hours will re-melt the resin. Examine resin for clarity before cooling to room temperature (23°C). Crystallization of epoxy resin is a common occurrence, but by minimizing temperature fluctuations during storage the tendency to crystallize will be reduced. If crystallization occurs a few hours at a slightly elevated temperature will return the resin to its original clarity and have no effect on the ultimate properties of the epoxy system. To the best of out knowledge, the information contained herein is accurate. However. STAR TECHNOLOGY. Inc.. does not assume any liability whatsoever tor the accuracy or completeness of the information contained herein. Final determination of the suitability of any material is the sole responsibility of the user The information contained herein is considered typical properties and is not intended to be used as specifications for our products This information is offered solely to assist purchaser in selecting the appropriate products for purchaser's own testing. All materials may present unknown hazards and should be used with caution Although certain hazards are described herein and in the material safety data sheet we cannot guarantee that these are the only hazards that exist Repeated and prolonged exposure to epoxy resins can cause sensitization or other allergic responses. 200 EXECUTIVE DRIVE. WATERLOO. IN 46793