[Code of Federal Regulations]
[Title 21, Volume 3]
[Revised as of April 1, 2006]
From the U.S. Government Printing Office via GPO Access
TITLE 21--FOOD AND DRUGS
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN
PART 177_INDIRECT FOOD ADDITIVES: POLYMERS--Table of Contents
Subpart C_Substances for Use Only as Components of Articles Intended for
Sec. 177.2600 Rubber articles intended for repeated use.
Rubber articles intended for repeated use may be safely used in
producing, manufacturing, packing, processing, preparing, treating,
packaging, transporting, or holding food, subject to the provisions of
(a) The rubber articles are prepared from natural and/or synthetic
polymers and adjuvant substances as described in paragraph (c) of this
(b) The quantity of any substance employed in the production of
rubber articles intended for repeated use shall not exceed the amount
reasonably required to accomplish the intended effect in the rubber
article and shall not be intended to accomplish any effect in food.
(c) Substances employed in the preparation of rubber articles
include the following, subject to any limitations prescribed:
(1) Substances generally recognized as safe for use in food or food
(2) Substances used in accordance with the provisions of a prior
sanction or approval.
(3) Substances that by regulation in parts 170 through 189 of this
chapter may be safely used in rubber articles, subject to the provisions
of such regulation.
(4) Substances identified in this paragraph (c)(4), provided that
any substance that is the subject of a regulation in parts 174, 175,
176, 177, 178 and Sec. 179.45 of this chapter conforms with any
specification in such regulation.
Brominated isobutylene-isoprene copolymers complying with Sec.
Butadiene-acrylonitrile-ethylene glycol dimethacrylate copolymers
containing not more than 5 weight percent of polymer units derived from
ethylene glycol dimethacrylate.
Butadiene-acrylonitrile-methacrylic acid copolymer.
Butadiene-styrene-methacrylic acid copolymer.
Chlorotrifluoroethylene-vinylidene fluoride copolymer.
Ethylene-propylene copolymer elastomers which may contain not more than
5 weight-percent of total polymer units derived from 5-methylene-2-
norbornene and/or 5-ethylidine-2-norbornene.
Ethylene-propylene-1,4-hexadiene copolymers containing no more than 8
weight percent of total polymer units derived from 1,4-hexadiene.
Hydrogenated butadiene/acrylonitrile copolymers (CAS Reg. No. 88254-10-
8) produced when acrylonitrile/butadiene copolymers are modified by
hydrogenation of the olefinic unsaturation to leave either: (1) Not more
than 10 percent trans olefinic unsaturation and no [alpha], [beta]-
olefinic unsaturation as determined by a method entitled ``Determination
of Residual [alpha], [beta]-Olefinic and Trans Olefinic Unsaturation
Levels in HNBR,'' developed October 1, 1991, by Polysar Rubber Corp.,
1256 South Vidal St., Sarnia, Ontario, Canada N7T 7MI; or (2) 0.4
percent to 20 percent olefinic unsaturation and Mooney viscosities
greater than 45 (ML 1 + 4 @ 100 [deg]C), as determined by ASTM Standard
Method D1646-92, ``Standard Test Method for Rubber--Viscosity and
Vulcanization Characteristics (Mooney Viscometer),'' which are both
incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR
part 51. Copies of these methods may be obtained from the Division of
Petition Control (HFS-215), Center for Food Safety and Applied
Nutrition, Food and Drug Administration, 5100 Paint Branch Pkwy.,
College Park, MD 20740, or may be examined at the Center for Food Safety
and Applied Nutrition's Library, 5100 Paint Branch Pkwy., College Park,
MD 20740, or 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. A copy of ASTM
Standard Method D1646-92 may also be obtained from the American Society
for Testing and Materials, 100 Barr Harbor Dr., West Conshohocken, PA
Polyamide/polyether block copolymers (CAS Reg. No. 77402-38-1 prepared
by reacting a copolymer of omega-laurolactam and adipic acid with
poly(tetramethylene ether glycol). The polyamide and polyether
components are reacted in ratios such that the polyamide component
constitutes a minimum of 30 weight-percent of total polymer units. The
copolymers may be used in contact with foods of Types I, II, III, IV, V,
VI, VII, VIII, and IX identified in table 1 of Sec. 176.170(c) of this
chapter at temperatures not to exceed 150 [deg]F except that those
copolymers prepared with less than 50 weight-percent of polyamide are
limited to use in contact with such foods at temperatures not to exceed
Polyester elastomers derived from the reaction of dimethyl
terephthalate, 1,4-butanediol, and [alpha]-hydro-omega-hydroxypoly
(oxytetramethylene). Additionally, trimethyl trimellitate may be used as
a reactant. The polyester elastomers may be used only in contact with
foods containing not more than 8 percent alcohol and limited to use in
contact with food at temperatures not exceeding 150 [deg]F.
Polyurethane resins (CAS Reg. Nos. 37383-28-1 or 9018-04-6) derived from
the reaction of diphenylmethane diisocyanate with 1,4-butanediol and
polytetramethylene ether glycol.
Polyurethane resins derived from reactions of diphenylmethane
diisocyanate with adipic acid and 1,4-butanediol.
Silicone basic polymer as described in ASTM method D1418-81, ``Standard
Practice for Rubber and Rubber Latices--Nomenclature,'' 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://
Silicone (Si) elastomers containing methyl groups.
Silicone (Psi) elastomers containing methyl and phenyl groups.
Silicone (Vsi) elastomers containing methyl and vinyl groups.
Silicone (Fsi) elastomers containing methyl and fluorine groups.
Silicone (PVsi) elastomers containing phenyl, methyl, and vinyl
Vinylidene fluoride-hexafluoropropylene copolymers (minimum number
average molecular weight 70,000 as determined by osmotic pressure in
methyl ethyl ketone).
Vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymers
(minimum number average molecular weight 100,000 as determined by
osmotic pressure in methyl ethyl ketone).
(ii) Vulcanization materials--(a) Vulcanizing agents.
4,4'-Bis(aminocyclohexyl)methane carbamate for use only as cross-linking
agent in the vulcanization of vinylidene fluoridehexafluoropropylene
copolymer and vinylidene fluoride-hexafluoropropylene-
tetrafluoroethylene copolymer elastomers identified under paragraph
(c)(4)(i) of this section and limited to use at levels not to exceed 2.4
percent by weight of such copolymers.
Diisopropyl xanthogen polysulfide (a 1:2:1 mixture of O,O-di(1-
thioformate, and O,O-di(1-methylethyl)pentathio-bis-thioformate) for use
as a cross linking agent in the vulcanization of natural rubber,
styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, and
ethylene-propylene terpolymers identified under paragraph (c)(4)(i) of
this section and limited to use at levels not to exceed 2.4 percent by
weight of such copolymers.
Hexamethylenediamine carbamate for use only as cross-linking agent in
the vulcanization of vinylidene fluoride-hexafluoropropylene copolymer
and vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene
copolymer elastomers identified under paragraph (c)(4)(i) of this
section and limited to use at levels not to exceed 1.5 percent by weight
of such copolymers.
(b) Accelerators (total not to exceed 1.5 percent by weight of
Butyraldehyde-aniline resin (iodine number 670-705).
Carbon disulfide-1,1'-methylenedipiperidine reaction product.
Diisopropyl xanthogen polysulfide (a 1:2:1 mixture of O,O-di(1-
thioformate, and O,O-di(1-methylethyl)pentathio-bis-thioformate).
Di(4-methylbenzoyl) peroxide (CAS Reg. No. 895-85-2) for use only as a
crosslinking agent in silicone polymers and elastomers identified under
paragraph (c)(4)(i) of this section at levels not to exceed 1 percent by
weight of such polymers and elastomers where the total of all
accelerators does not exceed 1.5 percent by weight of rubber product.
Dibutyl xanthogen disulfide.
N,N-Dimethylcyclohexylamine salt of dibutyldithiocarbamic acid.
Dipentamethylenethiuram hexasulfide (CAS Reg. No. 971-15-3).
Di-o-tolylguanidine salt of pyrocatecholborate.
Heptaldehyde-aniline resin (iodine number 430-445).
Stannous oleate for use only as an accelerator for silicone elastomers.
(1,1,4,4-Tetramethyltetramethylene)bis [tert-butyl peroxide].
Thiram (tetramethylthiuram disulfide).
Zinc butyl xanathate.
Zinc dibenzyl dithiocarbamate.
Ziram (zinc dimethyldithiocarbamate).
(c) Retarders (total not to exceed 10 percent of weight of rubber
(d) Activators (total not to exceed 5 percent by weight of rubber
product except magnesium oxide may be used at higher levels).
Fatty acid amines, mixed.
Magnesium oxide, light and heavy.
Oleic acid, dibutylamine salt (dibutylammonium oleate).
Tall oil fatty acids.
Zinc salts of fatty acids.
(iii) Antioxidants and antiozonants (total not to exceed 5 percent
by weight of rubber product).
Alkylated (C4 and/or C8) phenols.
BHT (butylated hydroxytoluene).
(CAS Reg. No. 991-84-4) for use only as a stabilizer at levels not to
exceed 0.5 percent by weight of the finished rubber product.
Butylated reaction product of p-cresol and dicyclopentadiene as
identified in Sec. 178.2010(b) of this chapter.
Butylated, styrenated cresols identified in Sec. 178.2010(b) of this
Diaryl-p-phenylenediamine, where the aryl group may be phenyl, tolyl, or
Hydroquinone monobenzyl ether.
Monooctyl- and dioctyldiphenylamine.
Phenyl-[beta]-naphthylamine-acetone aromatic amine resin (average
molecular weight 600; nitrogen content 5.3 percent).
o- and p-Phenylphenol.
Polybutylated (mixture) 4,4'-isopropylidenediphenol.
Styrenated cresols produced when 2 moles of styrene are made to react
with 1 mole of a mixture of phenol and o-, m-, and p-cresols so that the
final product has a Brookfield viscosity at 25 [deg]C of 1400 to 1700
Tri(mixed mono- and dinonylphenyl) phosphite.
Tri(nonylphenyl) phosphite-formaldehyde resins produced when 1 mole of
tri(nonylphenyl) phosphite is made to react with 1.4 moles of
formaldehyde or produced when 1 mole of nonylphenol is made to react
with 0.36 mole of formaldehyde and the reaction product is then further
reacted with 0.33 mole of phosphorus trichloride. The finished resins
have a minimum viscosity of 20,000 centipoises at 25 [deg]C, as
determined by LV-series Brookfield viscometer (or equivalent) using a
No. 4 spindle at 12 r.p.m., and have an organic phosphorus content of
4.05 to 4.15 percent by weight.
(iv) Plasticizers (total not to exceed 30 percent by weight of
rubber product unless otherwise specified).
n-Amyl n-decyl phthalate.
n-Butyl ester of tall oil fatty acids.
Fatty acids, hydrogenated.
Isooctyl ester of tall oil fatty acids.
a-Methylstyrene-vinyltoluene copolymer resins (molar ratio 1 a-
methylstyrene to 3 vinyltoluene).
Mineral oil; (1) In rubber articles complying with this section, not to
exceed 30 percent by weight; (2) Alone or in combination with waxes,
petroleum, total not to exceed 45 percent by weight of rubber articles
that contain at least 20 percent by weight of ethylene-propylene
copolymer elastomer complying with paragraph (c)(4)(i) of this section,
in contact with foods of Types I, II, III, IV, VI, VII, VIII, and IX
idenified in table 1 of Sec. 176.170(c) of this chapter.
n-Octyl n-decyl adipate.
n-Octyl n-decyl phthalate.
Petroleum hydrocarbon resin (cyclopentadiene type), hydrogenated.
Petroleum hydrocarbon resin (produced by the homo- and copolymerization
of dienes and olefins of the aliphatic, alicyclic, and monobenzenoid
arylalkene types from distillates of cracked petroleum stocks).
Petroleum hydrocarbon resin (produced by the catalytic polymerization
and subsequent hydrogenation of styrene, vinyltoluene, and indene types
from distillates of cracked petroleum stocks).
Petroleum oil, sulfonated.
n-Propyl ester of tall oil fatty acids.
Rapeseed oil vulcanized with rubber maker's sulfur.
Rosins and rosin derivatives identified in Sec. 175.105(c)(5) of this
Soybean oil vulcanized with rubber maker's sulfur.
Triethylene glycol dicaprate.
Triethylene glycol dicaprylate.
Xylene (or toluene) alkylated with dicyclopentadiene.
Asbestos fiber, chrysotile or crocidolite.
Carbon black (channel process or furnace combustion process; total
carbon black not to exceed 50 percent by weight of rubber product;
furnace combustion black content not to exceed 10 percent by weight of
rubber products intended for use in contact with milk or edible oils).
Cotton (floc, fibers, fabric).
Nylon (floc, fibers, fabric).
(vi) Colorants. Colorants used in accordance with Sec. 178.3297 of
(vii) Lubricants (total not to exceed 2 percent by weight of rubber
Fatty acid salts, sodium or potassium.
Naphthalene sulfonic acid-formaldehyde condensate, sodium salt.
Rosins and rosin-derivatives identified in Sec. 175.105(c)(5) of this
Sodium lauryl sulfate.
Tall oil mixed soap (calcium, potassium, and sodium).
(ix) Miscellaneous (total not to exceed 5 percent by weight of
Animal glue as described in Sec. 178.3120 of this chapter.
Azodicarbonamide as chemical blowing agent.
2-Anthraquinone sulfonic acid sodium salt for use only as polymerization
inhibitor in chloroprene polymers and not to exceed 0.03 percent by
weight of the chloroprene polymers.
1,2-Benzisothiazolin-3-one (CAS Reg. No. 2634-33-5) for use as a biocide
in uncured liquid rubber latex not to exceed 0.02 percent by weight of
the latex solids, where the total of all items listed in paragraph
(c)(4)(ix) of this section does not exceed 5 percent of the rubber
n-Butyllithium for use only as polymerization catalyst for
4-tert-Butyl-o-thiocresol as peptizing agent.
Di- and triethanolamine.
Diethyl xanthogen disulfide.
4-(Diiodomethylsulfonyl) toluene, Chemical Abstracts Service Registry
No. 20018-09-01, for use as an antifungal preservative at levels not to
exceed 0.3 percent by weight of the sealants and caulking materials.
Dodecyl mercaptan isomers, single or mixed.
a-(p-Nonylphenyl)-omega-hydroxypoly (oxyethylene) mixture of dihydrogen
phosphate and monohydrogen phosphate esters, barium salt; the nonyl
group is a propylene trimer isomer and the poly (oxyethylene) content
averages 9 moles; for use only as residual polymerization emulsifier at
levels not to exceed 0.7 percent by weight of ethylene-propylene-1,4-
hexadiene copolymers identified under paragraph (c)(4)(i) of this
4,4'-Oxybis (benzenesulfonhydrazide) as chemical blowing agent.
Sodium formaldehyde sulfoxylate.
Sodium salt of ethylenediamine tetraacetic acid and glycine.
Thioxylenois as peptizing agents.
Zinc 4-tert-butylthiophenate as peptizing agent.
(d) Rubber articles intended for use with dry food are so formulated
and cured under conditions of good manufacturing practice as to be
suitable for repeated use.
(e) Rubber articles intended for repeated use in contact with
aqueous food shall meet the following specifications: The food-contact
surface of the rubber article in the finished form in which it is to
contact food, when extracted with distilled water at reflux temperature,
shall yield total extractives not to exceed 20 milligrams per square
inch during the first 7 hours of extraction, nor to exceed 1 milligram
per square inch during the succeeding 2 hours of extraction.
(f) Rubber articles intended for repeated use in contact with fatty
foods shall meet the following specifications: The food-contact surface
of the rubber article in the finished form in which it is to contact
food, when extracted with n-hexane at reflux temperature, shall yield
total extractives not to exceed 175 milligrams per square inch during
the first 7 hours of extraction, nor to exceed 4 milligrams per square
inch during the succeeding 2 hours of extraction.
(g) In accordance with good manufacturing practice finished rubber
articles intended for repeated use in contact with food shall be
thoroughly cleansed prior to their first use in contact with food.
(h) The provisions of this section are not applicable to rubber
(i) Acrylonitrile copolymers identified in this section shall comply
with the provisions of Sec. 180.22 of this chapter.
[42 FR 14572, Mar. 15, 1977]
Editorial Note: ForFederal Register citations affecting Sec.
177.2600, see the List of CFR Sections Affected, which appears in the
Finding Aids section of the printed volume and on GPO Access.
Additives that reference this regulation: