Isobutylene-butene copolymers identified in paragraph (a) of this section may be safely used as components of articles intended for use in contact with food, subject to the provisions of this section.
(a) For the purpose of this section, isobutylene-butene copolymers consist of basic copolymers produced by the copolymerization of isobutylene with mixtures of n-butenes such that the finished basic copolymers contain not less than 45 weight percent of polymer units derived from isobutylene and meet the specifications prescribed in paragraph (b) of this section when tested by the methods described in paragraph (c) of this section.
(b) Specifications: ----------------------------------------------------------------------------------------------------------------
Maximum
Isobutylene-butene copolymers Molecular weight (range) Viscosity (range) bromine
value----------------------------------------------------------------------------------------------------------------1. Used as release agents in petroleum 300 to 5,000............ 40 to 20,000 seconds Saybolt at 200 40
wax complying with Sec. 178.3710 of F.
this chapter.2. Used as plasticizers in 300 to 5,000............ 40 to 20,000 seconds Saybolt at 200 40
polyethylene or polypropylene F.
complying with Sec. 177.1520, and in
polystyrene complying with Sec.
177.1640.3. Used as components of nonfood 300 to 5,000............ 40 to 20,000 seconds Saybolt at 200 40
articles complying with Secs. F.
175.300, 176.170, 176.210,
177.2260(d)(2), 177.2800, and
178.3570 (provided that addition to
food does not exceed 10 parts per
million), or Sec. 176.180 of this
chapter.4. Used as production aids in the 150 to 5,000............ Less than 20,000 seconds Saybolt at 90.
manufacture of expanded (foamed) 200 F.
polystyrene articles complying with
Sec. 177.1640 of this chapter.5. Used in release coatings on 150 to 5,000............ Less than 20,000 seconds Saybolt at 90
backings or linings for pressure- 200 F.
sensitive adhesive labels complying
with Sec. 175.125 of this chapter.----------------------------------------------------------------------------------------------------------------
(c) The analytical methods for determining whether isobutylene-butene copolymers conform to the specifications in paragraph (b) are as follows:
(1) Molecular weight. Molecular weight shall be determined by American Society for Testing and Materials (ASTM) method D2503-82, ``Standard Test Method for Molecular Weight (Relative Molecular Mass) of Hydrocarbons by Thermoelectric Measurement of Vapor Pressure,'' which is incorporated by reference. Copies may be obtained from the American Society for Testing Materials, 100 Barr Harbor Dr., West Conshohocken, Philadelphia, PA 19428-2959, or may be examined at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
(2) Viscosity. Viscosity shall be determined by ASTM method D445-74, ``Test for Kinematic Viscosity of Transparent and Opaque Liquids,'' which is incorporated by reference. The availability of this incorporation by reference is given in paragraph (c)(1) of this section.
(3) Maximum bromine value. Maximum bromine value shall be determined by ASTM method D1492-78, ``Standard Test Method for Bromine Index of Aromatic Hydrocarbons by Coulometric Titration,'' which is incorporated by reference. The availability of this incorporation by reference is given in paragraph (c)(1) of this section.
(d) The provisions of this section are not applicable to isobutylene-butene copolymers used as provided under Sec. 175.105 of this chapter. [52 FR 11641, Apr. 10, 1987, as amended at 63 FR 36175, July 2, 1998] Sec. 177.1440 4,4'-Isopropylidenediphenol-epichlorohydrin resins minimum molecular weight 10,000.
4,4'-Isopropylidenediphenol-epichlo-rohydrin resins having a minimum molecular weight of 10,000 may be safely used as articles or components of articles intended for use in producing, manufacturing, packing, processing, preparing, treating, packaging, transporting, or holding food in accordance with the following prescribed conditions:
(a) 4,4'-Isopropylidenediphenol-ep-ichlorohydrin resins consist of basic resins produced by the condensation of equimolar amounts of 4,4'-isopropylidenediphenol and epichlorohydrin terminated with phenol, to which may have been added certain optional adjuvant substances required in the production of the resins.
(b) The optional adjuvant substances required in the production of the resins may include substances generally recognized as safe in food, substances used in accordance with a prior sanction or approval, and the following: ------------------------------------------------------------------------
List of substances Limitations------------------------------------------------------------------------Butyl alcohol............................ Not to exceed 300 p.p.m. as
residual solvent in finished
resin.Ethyl alcohol............................Toluene.................................. Not to exceed 1,000 p.p.m. as
residual solvent in finished
resin.------------------------------------------------------------------------
(c) 4,4'-Isopropylidenediphenol-ep-ichlorohydrin resins shall meet the following nonvolatile extractives limitations:
(1) Maximum extractable nonvolatile fraction of 2 parts per million when extracted with distilled water at 70 C for 2 hours, using a volume-to-surface ratio of 2 milliliters per square inch.
(2) Maximum extractable nonvolatile fraction of 3 parts per million when extracted with n-heptane at 70 C for 2 hours, using a volume-to-surface ratio of 2 milliliters per square inch.
(3) Maximum extractable nonvolatile fraction of 6 parts per million when extracted with 10 percent (by volume) ethyl alcohol in distilled water at 70 C for 2 hours, using a volume-to-surface ratio of 2 milliliters per square inch.
(d) The provisions of this section are not applicable to 4,4'-isopropylidene-diphenol-epichlorohydrin resins listed in other sections of subchapter B of this chapter.