What is "polyamide-imide"

Polyamide-imides are either thermosetting or thermoplastic, amorphous polymers that have exceptional mechanical, thermal and chemical resistant properties. Polyamide-imides are used extensively as wire coatings in making magnet wire. They are prepared from isocyanates and TMA (trimellic acid-anhydride) in n-methyl-2-pyrrolidone (NMP). A prominent distributor of polyamide-imides is Solvay Specialty Polymers, which uses the trademark Torlon.

Polyamide-imides display a combination of properties from both polyamides and polyimides, such as high strength, melt processibility, exceptional high heat capability, and broad chemical resistance. Polyamide-imide polymers can be processed into a wide variety of forms, from injection or compression molded parts and ingots, to coatings, films, fibers and adhesives. Generally these articles reach their maximum properties with a subsequent thermal cure process.

Other high-performance polymers in this same realm are polyetheretherketones and polyimides.