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Unsaturated polyester resin chemical propertie

Jan 28, 2019

Unsaturated polyester resin chemical properties

The unsaturated polyester is a linear polymer compound having a multifunctional group having a polyester chain bond and an unsaturated double bond in its skeleton main chain, and a carboxyl group and a hydroxyl group at each end of the macromolecular chain.

The double bond on the main chain can be copolymerized and crosslinked with the vinyl monomer to convert the unsaturated polyester resin from a soluble, fusible state to an insoluble, infusible state.

The ester bond on the main chain can undergo a hydrolysis reaction, and an acid or a base can accelerate the reaction. When copolymerized with styrene, the hydrolysis reaction can be greatly reduced.

In acidic media, hydrolysis is reversible and incomplete, so polyester can withstand the attack of acidic medium; in alkaline medium, due to the formation of a resonance-stable carboxylate anion, hydrolysis becomes irreversible, so polyester is resistant to alkali. Poor sex.

The carboxyl group at the end of the polyester chain can react with an alkaline earth metal oxide or hydroxide [e.g., MgO, CaO, Ca(OH)2, etc.) to expand the molecular chain of the unsaturated polyester, eventually forming a complex. The molecular chain extension can be such that the initial viscosity is 0.1 to 1.0 Pa·s of a viscous liquid resin, and the viscosity is sharply increased to 103 Pa·s or more in a short period of time until it becomes a non-flowable, non-sticky gel-like substance. When the resin is in this state, it is not crosslinked, it is still soluble in a suitable solvent, and has good fluidity upon heating.

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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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