Notice2026-18268
Superfund Tax on Chemical Substances; Request To Modify List of Taxable Substances; Notice of Filing for Acrylonitrile-butadiene Rubber; x=3,344.33, y=1,335.09, a=2.98
Primary source
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Published
September 9, 2026
Issuing agencies
Treasury DepartmentInternal Revenue Service
Abstract
This notice of filing announces that a petition has been filed requesting that acrylonitrile-butadiene rubber ((C<INF>4</INF>H<INF>6</INF>)<INF>x</INF>- (C<INF>3</INF>H<INF>3</INF>N)<INF>y</INF>- (C<INF>25</INF>H<INF>44</INF>OS<INF>2</INF>)<INF>a</INF>; x=3,344.33, y=1,335.09, a=2.98), also known as "NBR," be added to the list of taxable substances. This notice of filing also requests comments on the petition. This notice of filing is not a determination that the list of taxable substances is modified.
Full Text
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<title>Federal Register, Volume 91 Issue 173 (Wednesday, September 9, 2026)</title>
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[Federal Register Volume 91, Number 173 (Wednesday, September 9, 2026)]
[Notices]
[Pages 57450-57451]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-18268]
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DEPARTMENT OF THE TREASURY
Internal Revenue Service
Superfund Tax on Chemical Substances; Request To Modify List of
Taxable Substances; Notice of Filing for Acrylonitrile-butadiene
Rubber; x=3,344.33, y=1,335.09, a=2.98
AGENCY: Internal Revenue Service (IRS), Treasury.
ACTION: Notice of filing and request for comments.
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SUMMARY: This notice of filing announces that a petition has been filed
requesting that acrylonitrile-butadiene rubber
((C<INF>4</INF>H<INF>6</INF>)<INF>x</INF>-
(C<INF>3</INF>H<INF>3</INF>N)<INF>y</INF>-
(C<INF>25</INF>H<INF>44</INF>OS<INF>2</INF>)<INF>a</INF>; x=3,344.33,
y=1,335.09, a=2.98), also known as ``NBR,'' be added to the list of
taxable substances. This notice of filing also requests comments on the
petition. This notice of filing is not a determination that the list of
taxable substances is modified.
DATES: Written comments and requests for a public hearing must be
received on or before November 9, 2026.
ADDRESSES: Commenters are encouraged to submit public comments or
requests for a public hearing relating to this petition electronically
via the Federal eRulemaking Portal at <a href="https://www.regulations.gov">https://www.regulations.gov</a>
(indicate public docket number IRS-2026-1029 or acrylonitrile-butadiene
rubber; x=3,344.33, y=1,335.09, a=2.98) by following the online
instructions for submitting comments. Comments cannot be edited or
withdrawn once submitted to the Federal eRulemaking Portal.
Alternatively, comments and requests for a public hearing may be mailed
to: Internal Revenue Service, Attn: CC:PA:01:PR (Notice of Filing for
acrylonitrile-butadiene rubber; x=3,344.33, y=1,335.09, a=2.98), Room
5203, P.O. Box 7604, Ben Franklin Station, Washington, DC 20044. All
comments received are part of the public record and subject to public
disclosure. All comments received will be posted without change to
<a href="https://www.regulations.gov">https://www.regulations.gov</a>, including any personal information
provided. You should submit only information that you wish to make
publicly available. If a public hearing is scheduled, notice of the
time and place for the hearing will be published in the Federal
Register.
FOR FURTHER INFORMATION CONTACT: Jacob W. Peeples at (202) 317-6855
(not a toll-free number).
SUPPLEMENTARY INFORMATION:
Request To Add Substance to the List
(a) Overview. A petition was filed pursuant to Rev. Proc. 2022-26
(2022-29 I.R.B. 90), as modified by Rev. Proc. 2023-20 (2023-15 I.R.B.
636), requesting that NBR be added to the list of taxable substances
under section 4672(a) of the Internal Revenue Code (List). The petition
requesting the addition of NBR to the List is based on weight and
contains the information detailed in paragraph (b) of this document.
The information is provided for public notice and comment pursuant to
section 9 of Rev. Proc. 2022-26. The publication of petition
information in this notice of filing is not a determination and does
not constitute Treasury Department or IRS confirmation of the accuracy
of the information published.
(b) Petition Content.
(1) Substance name: Acrylonitrile-butadiene rubber
((C<INF>4</INF>H<INF>6</INF>)<INF>x</INF>-
(C<INF>3</INF>H<INF>3</INF>N)<INF>y</INF>-
(C<INF>25</INF>H<INF>44</INF>OS<INF>2</INF>)<INF>a</INF>; x=3,344.33,
y=1,335.09, a=2.98).
The substance is also known as NBR.
(2) Petitioner: Zeon Chemicals L.P. is an importer and exporter of
NBR.
(3) Proposed classification numbers:
(i) HTSUS number: 4002.59.0000.
(ii) Schedule B number: 4002.59.0000.
(iii) CAS number: 9003-18-3, 8.
(4) Petition filing dates:
(i) Petition filing date for purposes of making a determination:
November 21, 2025.
(ii) Petition filing date for purposes of section 11.02 of Rev.
Proc. 2022-26, as modified by section 3 of Rev. Proc. 2023-20: April 1,
2023.
(5) Description from petition: NBR is an oil-resistant synthetic
rubber produced from a copolymer of acrylonitrile and butadiene. Its
main applications are in fuel hoses, gaskets, rollers, and other
products in which oil resistance is required. NBR is made from
butadiene, propylene, ammonia, benzene, methane, and sodium hydroxide.
Taxable chemicals constitute 79.51 percent by weight of the materials
used to produce this substance.
(6) Process identified in petition as predominant method of
production of substance: The predominant method of producing NBR is
through emulsion polymerization of butadiene and acrylonitrile.
Emulsion polymerization involves application of emulsifier to emulsify
hydrophobic polymers through aqueous phase by amphipathic emulsifier,
then generation of free radicals with either a water or oil soluble
initiators. It is characterized by reduction of bimolecular termination
of free radicals due to segregation of free radicals among the discrete
monomer-swollen polymer particles.
The latex particles size ranged from 10 nm to 1,000 nm in a
diameter and are generally spherical. A typical of particle consist of
1-10,000 macromolecules, where macromolecule contains about 100-106
monomer units. The polymer latex is coagulated, pressed, and dried to
remove moisture. Acrylonitrile monomer is produced by the SOHIO process
(i.e., catalytic ammoxidation of propylene). Phenol, 2-methyl-4,6-
bis[(octylthio)methyl] is produced by reacting o-cresol, 1-octanethiol,
and formaldehyde. o-Cresol is produced from the methylation of phenol
using methanol. Phenol is produced via the Hock process (i.e., the
partial oxidation of cumene via the Hock rearrangement). Cumene is
produced via the Friedel-Crafts alkylation of benzene with propylene.
Methanol is made from syngas. Hydrogen is produced from steam-methane
reforming. 1-Octanethiol is produced by from halogen substituted octane
and sodium hydrosulfide. Halogen substituted octane is produced by
reacting octane and a halogen (e.g., iodine). Sodium hydrosulfide is
produced by the reaction of sodium hydroxide with hydrogen sulfide.
Formaldehyde is produced by the catalytic oxidation of methanol.
(7) Stoichiometric material consumption equation, based on process
identified as predominant method of production: x
C<INF>4</INF>H<INF>6</INF> (butadiene) + y [C<INF>3</INF>H<INF>6</INF>
(propylene) + NH<INF>3</INF> (ammonia) + \3/2\ O<INF>2</INF>] + a
[C<INF>6</INF>H<INF>6</INF> (benzene) + C<INF>3</INF>H<INF>6</INF>
(propylene) + \3/2 \CH<INF>4</INF> (methane) + 2 NaOH (sodium
hydroxide) + 2 O<INF>2</INF> (oxygen) + 3 CO (syngas) + 2
C<INF>8</INF>H<INF>18</INF> (octane) + 2 I<INF>2</INF> (iodine) + 2
H<INF>2</INF>S (hydrogen sulfide)] [rarr]
(C<INF>4</INF>H<INF>6</INF>)<INF>x</INF>-
(C<INF>3</INF>H<INF>3</INF>N)<INF>y</INF>-
(C<INF>25</INF>H<INF>44</INF>OS<INF>2</INF>)<INF>a</INF> (NBR) + a
C<INF>3</INF>H<INF>6</INF>O (acetone) + \3/2\a CO<INF>2</INF> + (3y+4a)
H<INF>2</INF>O + 2a HI + 2a NaI.
(8) Tax rate calculated by Petitioner, based on Petitioner's
conversion factors for taxable chemicals used in production of
substance:
(i) Tax rate: $9.54 per ton.
(ii) Conversion factors: 0.71 for butadiene, 0.22 for propylene,
0.09 for
[[Page 57451]]
ammonia, 0.0009 for benzene, 0.0003 for methane, and 0.0009 for sodium
hydroxide.
(9) Public docket number: IRS-2026-1029.
Michael H. Beker,
Senior Counsel (Energy, Credits, and Excise Tax), IRS Office of Chief
Counsel.
[FR Doc. 2026-18268 Filed 9-8-26; 8:45 am]
BILLING CODE 4831-GV-P
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