[Code of Federal Regulations]
[Title 21, Volume 3]
[Revised as of April 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR177.1020]

[Page 228-229]
 
                        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. 177.1020  Acrylonitrile/butadiene/styrene co-polymer.

    Acrylonitrile/butadiene/styrene copolymer identified in this section 
may be safely used as an article or component of articles intended for 
use with all foods, except those containing alcohol, under conditions of 
use E, F, and G described in table 2 of Sec. 176.170(c) of this chapter.
    (a) Identity. For the purpose of this section, the acrylonitrile/
butadiene/styrene copolymer consists of:
    (1) Eighty-four to eighty-nine parts by weight of a matrix polymer 
containing 73 to 78 parts by weight of acrylonitrile and 22 to 27 parts 
by weight of styrene; and
    (2) Eleven to sixteen parts by weight of a grafted rubber consisting 
of (i) 8 to 13 parts of butadiene/styrene elastomer containing 72 to 77 
parts by weight of butadiene and 23 to 28 parts by weight of styrene and 
(ii) 3 to 8 parts by weight of a graft polymer having the same 
composition range as the matrix polymer.
    (b) Adjuvants. The copolymer identified in paragraph (a) of this 
section may contain adjuvant substances required in its production. Such 
adjuvants may include substances generally recognized as safe in food, 
substances used in accordance with prior sanction, substances permitted 
in this part, and the following:

------------------------------------------------------------------------
                 Substance                           Limitations
------------------------------------------------------------------------
2-Mercapto- ethanol.......................  The finished copolymer shall
                                             contain not more than 100
                                             ppm 2-mercaptoethanol
                                             acrylonitrile adduct as
                                             determined by a method
                                             titled ``Analysis of
                                             Cycopac Resin for Residual
                                             -(2-
                                             Hydroxyethylmercapto)
                                             propionitrile,'' which is
                                             incorporated by reference.
                                             Copies are available from
                                             the Bureau of Foods (HFS-
                                             200), Food and Drug
                                             Administration, 200 C St.
                                             SW., Washington, DC 20204,
                                             or available for inspection
                                             at the Office of the
                                             Federal Register, 800 North
                                             Capitol Street, NW., suite
                                             700, Washington, DC 20408.
------------------------------------------------------------------------

    (c) Specifications. (1) Nitrogen content of the copolymer is in the 
range of 16 to 18.5 percent as determined by Micro-Kjeldahl analysis.
    (2) Residual acrylonitrile monomer content of the finished copolymer 
articles is not more than 11 parts per million as determined by a gas 
chromatographic method titled ``Determination of Residual Acrylonitrile 
and Styrene Monomers-Gas Chromatographic Internal Standard Method,'' 
which is incorporated by reference. Copies are available from the Center 
for Food Safety and Applied Nutrition (HFS-200), Food and Drug 
Administration, 200 C St. SW., Washington, DC 20204, or available for 
inspection at the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC 20408.
    (d) Extractive limitations. (1) Total nonvolatile extractives not to 
exceed

[[Page 229]]

0.0005 milligram per square inch surface area when the finished food 
contact article is exposed to distilled water, 3 percent acetic acid, or 
n-heptane for 8 days at 120  deg.F.
    (2) The finished food-contact article shall yield not more than 
0.0015 milligram per square inch of acrylonitrile monomer when exposed 
to distilled water and 3 percent acetic acid at 150  deg.F for 15 days 
when analyzed by a polarographic method titled ``Extracted Acrylonitrile 
by Differential Pulse Polarography,'' which is incorporated by 
reference. Copies are available from the Center for Food Safety and 
Applied Nutrition (HFS-200), Food and Drug Administration, 200 C St. 
SW., Washington, DC 20204, or available for inspection at the Office of 
the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC 20408.
    (e) Acrylonitrile copolymers identified in this section shall comply 
with the provisions of Sec. 180.22 of this chapter.
    (f) Acrylonitrile copolymers identified in this section are not 
authorized to be used to fabricate beverage containers.

[42 FR 14572, Mar. 15, 1977, as amended at 42 FR 48543, Sept. 23, 1977; 
47 FR 11841, Mar. 19, 1982; 54 FR 24897, June 12, 1989]