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How to cure unsaturated polyester resin ?

Jan 28, 2019

The curing process of unsaturated polyester resin can be divided into three stages, namely:

1. Gel stage (stage A): the stage from the addition of the curing agent and the accelerator until the resin condenses into a jelly form and loses fluidity. In this segment, the resin can be melted and dissolved in certain solvents (such as ethanol, acetone, etc.). This phase takes about a few minutes to tens of minutes.

2. Hardening stage (B stage): From the time of the resin gel, until it becomes a stage with sufficient hardness to reach a substantially non-stick state. In this stage, the resin swells when it comes into contact with certain solvents (such as ethanol, acetone, etc.) but does not dissolve. It softens when heated but does not melt completely. This phase takes about tens of minutes to several hours.

3. Maturing stage (C stage): It is placed at room temperature, and after the hardening, it reaches the hardness required by the product, and has stable physical and chemical properties for use. In this stage, the resin neither dissolves nor melts. The post-cure we usually refer to refers to this stage. This knot is usually a very long process. It usually takes days or weeks or even longer.

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Neweco is one of the leading unsaturated polyester resin manufacturers and  suppliers,widely used in automobiles, ships, rail transit, wind power  generation, pipe cans, heat and corrosion protection, building  materials, stone repair, sanitary ware, artificial stone and other  industries. Suitable for hand lay-up, spray, pultrusion, winding,  molding, vacuum introduction / RTM, casting and other molding processes. Neweco Resin is committed to excellence and focuses on the application  of composite materials to provide customers with comprehensive  solutions.

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