Definition of polyester resin
: any of various synthetic resins or plastics consisting of or made from polyesters: such as a : alkyd b : a resin that has the same chemical composition as the common polyester fiber but that is extruded as a film (as for use in packaging, as electrical insulation, or as a base for magnetic recording tapes) c : a thermosetting resin that is made from an unsaturated polyester (as one formed from a glycol and maleic acid or fumaric acid), cured by copolymerization (as with styrene), and often reinforced with fillers (as glass fibers) and that is used chiefly in impregnating and laminating and in making cast and molded products
Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.
Start your free trial today and get unlimited access to America's largest dictionary, with:
- More than 250,000 words that aren't in our free dictionary
- Expanded definitions, etymologies, and usage notes
- Advanced search features
- Ad free!
Seen and Heard
What made you want to look up polyester resin? Please tell us where you read or heard it (including the quote, if possible).