Code of Federal Regulations Title 21. Food and Drugs § 21.177.2415 Poly(aryletherketone) resins

(a) Identity. For the purposes of this section, poly(aryletherketone) resins are poly(p-oxyphenylene p-oxyphenylene p-carboxyphenylene) resins (CAS Reg. No. 29658–26–2) produced by the polymerization of hydroquinone and 4,4′–difluorobenzophenone, and have a minimum weight-average molecular weight of 12,000, as determined by gel permeation chromatography in comparison with polystyrene standards, and a minimum mid-point glass transition temperature of 142 °C, as determined by differential scanning calorimetry.

(b) Optional adjuvant substances. The basic resins identified in paragraph (a) may contain optional adjuvant substances used in their production. These adjuvants may include substances described in § 174.5(d) of this chapter and the following:

(c) Extractive limitations. The finished food contact article, when extracted at reflux temperatures for 2 hours with the following four solvents, yields in each extracting solvent net chloroform soluble extractives not to exceed 0.05 milligrams per square inch of food contact surface:  Distilled water, 50 percent (by volume) ethanol in distilled water, 3 percent acetic acid in distilled water, and n-heptane. In testing the final food contact article, a separate test sample shall be used for each extracting solvent.