[Code of Federal Regulations] [Title 21, Volume 3] [Revised as of April 1, 2002] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR177.1040] [Page 232-233] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 177--INDIRECT FOOD ADDITIVES: POLYMERS--Table of Contents Subpart B--Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces Sec. 177.1040 Acrylonitrile/styrene copoly-mer. Acrylonitrile/styrene copolymers identified in this section may be safely used as a component of packaging materials subject to the provisions of this section. (a) Identity. For the purposes of this section acrylonitrile/styrene copoly-mers are basic copolymers meeting the specifications prescribed in paragraph (c) of this section. (b) Adjuvants. (1) The copolymers identified in paragraph (c) of this section may contain adjuvant substances required in their production, with the exception that they shall not contain mercaptans or other substances which form reversible complexes with acryl-onitrile monomer. Permissible adjuvants may include substances generally recognized as safe in food, substances used in accordance with prior sanction, substances permitted under applicable regulations in this part, and those authorized in paragraph (b)(2) of this section. (2) The optional adjuvants for the acrylonitrile/styrene copolymer identified in paragraphs (c) (1) and (3) of this section are as follows: ------------------------------------------------------------------------ Substances Limitation ------------------------------------------------------------------------ Condensation polymer of toluene 0.15 pct maximum. sulfonamide and formaldehyde. ------------------------------------------------------------------------ (c) Specifications. ---------------------------------------------------------------------------------------------------------------- Maximum Maximum residual extractable acrylonitrile Nitrogen fractions at Conformance with Acrylonitrile/styrene copolymers monomer content content of specified certain specifications of finished copolymer temperatures and article times ---------------------------------------------------------------------------------------------------------------- 1. Acrylonitrile/styrene 80 ppm\1\....... 17.4 to 19 pct. Total nonvolatile Minimum number average copolymer consisting of the extractives not molecular weight is copolymer produced by to exceed 0.01 mg/ 30,000.\1\ polymerization of 66-72 parts in \2\ surface by weight of acrylonitrile and area of the food 28-34 parts by weight of contact article styrene; for use with food of when exposed to Type VI-B identified in table 1 distilled water of Sec. 176.170(c) of this and 3 pct acetic chapter under conditions of use acid for 10 d at C, D, E, F, G described in 66 C (150 F). table 2 of Sec. 176.170(c) of The extracted this chapter. copolymer shall not exceed 0.001 mg/in \2\ surface area of the food contact article when exposed to distilled water and 3 pct acetic acid for 10 d at 66 C (150 F) \1\. [[Page 233]] 2. Acrylonitrile/styrene 50 ppm\1\....... 12.2 to 17.2 Extracted Minimum 10 pct solution copolymer consisting of the pct. copolymer not to viscosity at 25 C (77 copolymer produced by exceed 2.0 ppm in F) is 10cP.\1\ polymerization of 45-65 parts aqueous extract by weight of acrylonitrile and or n-heptane 35-55 parts by weigth of extract obtained styrene; for use with food of when 100 g sample Types, I, II, III, IV, V, VI of the basic (except bottles), VII, VIII, copolymer in the and IX identified in table 1 of form of particles Sec. 176.170(c) of this of a size that chapter under conditions B (not will pass through to exceed 93 C (200 F)), C, D, a U.S. Standard E, F, G described in table 2 of Sieve No. 6 and Sec. 176.170(c) of this that will be held chapter. on a U.S. Standard Sieve No. 10 is extracted with 250 mil of deionized water or reagent grade n-heptane at reflux temperature for 2 h.\1\ 3. Acrylonitrile/styrene 0.10 ppm 17.4 to 19 pct. Total nonvolatile Maximum carbon dioxide copolymer consisting of the (calculated on extractives not permeability at 23 C copolymer produced by the basis of to exceed 0.01 mg/ (73 F) for the polymerization of 66-72 parts the weight of in \2\ surface finished article is by weight of acrylonitrile and the area of the food 0.04 barrer.\3\ 28-34 parts by weight of acrylonitrile contact article styrene; for use with food of copolymer resin when exposed to Types VI-A and VI-B identified in the finished distilled water in table 1 of Sec. 176.170(c) articles).\2\ and 3 pct acetic of this chapter under acid for 10 d at conditions of use C, D, E, F, G 66 C (150 F). described in table 2 of Sec. The extracted 176.170(c) of this chapter. copolymer shall not exceed 0.001 mg/in \2\ surface area of the food contact article when exposed to distilled water and 3 pct acetic acid for 10 d at 66 C (150 F).\1\. ---------------------------------------------------------------------------------------------------------------- \1\ Use methods for determination of residual acrylonitrile monomer content, maximum extractable fraction, number average molecular weight, and solution viscosity, titled: ``Determination of Residual Acrylonitrile and Styrene Monomers-Gas Chromatographic Internal Standard Method''; ``Infrared Spectrophotometric Determination of Polymer Extracted from Barex 210 Resin Pellets''; ``Procedure for the Determination of Molecular Weights of Acrylonitrile/Styrene Copolymers,'' and ``Analytical Method for 10% Solution Viscosity of Tyril,'' which are incorproated by reference. Copies are available from the Center for Food Safety and Applied Nutrition (HFS- 200), 5100 Paint Branch Pkwy., College Park, MD 20740, or may be examined at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC 20408. \2\ As determined by the method titled ``Headspace Sampling and Gas-Solid Chromatographic Determination of Residual Acrylonitrile in Acrylonitrile Copolyemr Solutions,'' which is incorporated by reference. Copies are available from the Center for Food Safety and Applied Nutrition (HFS-200), 5100 Paint Branch Pkwy., College Park, MD 20740, or may be examined at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC 20408. \3\ As determined on appropriately shaped test samples of the article or acrylonitrile copolymer layer in a multilayer construction by ASTM method D-1434-82, ``Standard Method for Determining Gas Permeability Characteristics of Plastic Film and Sheeting,'' which is incorporated by reference. Copies are available from the Center for Food Safety and Applied Nutrition (HFS-200), 5100 Paint Branch Pkwy., College Park, MD 20740, and the American Society for Testing Materials, 1916 Race Street, Philadelphia, PA 19103, or may be examined at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC 20408. (d) Interim listing. Acrylonitrile copolymers identified in this section shall comply with the provisions of Sec. 180.22 of this chapter. (e) Acrylonitrile copolymer identified in this section may be used to fabricate beverage containers only if they comply with the specifications of item 3 in paragraph (c) of this section. [42 FR 14572, Mar. 15, 1977, as amended at 42 FR 48543, Sept. 23, 1977; 47 FR 11841, Mar. 19, 1982; 49 FR 36643, Sept. 19, 1984; 52 FR 33803, Sept. 8, 1987]