subchapter_subject: "FOOD FOR HUMAN CONSUMPTION (CONTINUED)"
part_code: "177"
part_subject: "INDIRECT FOOD ADDITIVES: POLYMERS"
subpart_code: "B"
subpart_subject: "Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces"
section_number: "177.1556"
section_subject: "Polyaryletherketone resins."
cfr_reference: "21 CFR 177.1556"
title_name: "Title 21"
title_subject: "Food and Drugs"
parts_covered: "Parts 170 to 199"
revised_date: "Revised as of April 1, 2019"
publication_date: "As of April 1, 2019"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
---
The poly(oxy-1,4-phenylenecarbonyl-1,4-phenyleneoxy-1,4-phenylenecarbonyl-1,4-phenylenecarbonyl-1,4-phenylene) resins (CAS Reg. No. 55088-54-5 and CAS Reg. No. 60015-05-6 and commonly referred to as polyaryletherketone resins) identified in paragraph (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. Polyaryletherketone resins consist of basic resins produced by reacting 4,4′-diphenoxy benzophenone and terephthaloyl dichloride in such a way that the finished resins have a minimum weight average molecular weight of 20,000 grams per mole, as determined by light scattering measurements in sulfuric acid at room temperature.
(b)Optional adjuvant substances. The basic polyaryletherketone resins identified in paragraph (a) of this section may contain optional adjuvant substances required in the production of such basic resins. These adjuvants may include substances used in accordance with § 174.5 of this chapter and the following:
(c)Extractive limitations. The finished food-contact article yields net total extractives in each extracting solvent not to exceed 0.052 milligram per square inch (corresponding to 0.008 milligram per square centimeter) of food-contact surface, when extracted at reflux temperature for 2 hours with the following solvents: Distilled water, 50 percent (by volume) ethyl alcohol in distilled water, 3 percent acetic acid (by weight) in distilled water, and n-heptane.
(d)In testing the finished food-contact article made of polyaryletherketone resin, use a separate test sample for each required extracting solvent.