Polyester Resin, in its saturated form used for powder coatings, is evaluated under a standard guide covering both raw powder and cured film testing. This page covers that testing framework and what accelerated weathering research shows about why durability varies by binder type — not a fixed property of “polyester” alone.
What is it?
Polyester Resin (saturated), used in powder coatings, falls under ASTM D3451, a guide for selecting and using test procedures across thermoplastic and thermoset coating powders — from raw powder characteristics through cured film performance.
Why should I use it?
- It’s evaluated within an established, broad testing framework covering the full process from powder to cured film — see “What is it?” above.
- Its weathering durability depends heavily on the specific binder system used, not on being “polyester” alone — see Limitations.
How it’s used
In Plastics & Polymers, Polyester Resin (saturated) is used as a powder coating material evaluated under the procedures covered by ASTM D3451.
Limitations — when it isn’t the right choice
- Not every saturated polyester powder coating weathers the same way — the specific binder system determines whether it holds up. A 2016 peer-reviewed study ran accelerated weathering tests (SUNTEST, UVA, and UVB) on four standard-durable and seven superdurable types of polyester thermosetting powder coatings. Degradation behavior differed mainly by the specific reactive binder system: some formulations showed aging driven by hydrolysis, while others showed an increase in degree of polymerization instead, as measured by DSC. Overall gloss and color retention was good, but varied by type. This was documented as a comparison across multiple commercial coating types; it should not be assumed that a given saturated polyester grade is “standard” or “superdurable” without checking its own classification and weathering data.