---
kind: "section"
citation: "21 C.F.R. § 177.2415"
title: "21"
number: "177.2415"
heading: "Poly(aryletherketone) resins."
url: "https://uscodex.org/cfr/21/177.2415"
---

# §177.2415. Poly(aryletherketone) resins.


Poly(aryletherketone) resins identified in [paragraph (a)](#a) of this section may be safely used as articles or components of articles intended for repeated use in contact with food subject to the provisions of this section.

- (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)](#a) may contain optional adjuvant substances used in their production. These adjuvants may include substances described in [§ 174.5(d)](/cfr/21/174.5.md?p=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.

## Notes

### Amendments

[63 FR 20315, Apr. 24, 1998]

### Authority

Authority: 21 U.S.C. 321, 342, 348, 379e.

### Source

Source: 42 FR 14572, Mar. 15, 1977, unless otherwise noted.

### Amendments

[63 FR 20315, Apr. 24, 1998]