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                                                                     Exhibit 4.4





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                              CROMPTON CORPORATION

                              6.125% NOTES DUE 2006






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                          SECOND SUPPLEMENTAL INDENTURE
                           DATED AS OF AUGUST 5, 2004

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                         U.S. BANK, NATIONAL ASSOCIATION
                                   AS TRUSTEE





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     SECOND SUPPLEMENTAL INDENTURE, dated as of August 5, 2004 (this "Second
Supplemental Indenture"), between CROMPTON CORPORATION, a Delaware corporation
(the "Company"), as successor to Witco Corporation, and U.S. BANK, National
Association, a national banking association duly organized under the laws of the
United States, as successor to Fleet National Bank of Connecticut ("Fleet"), as
trustee..

     WHEREAS, the Company and the The Chase Manhattan Bank, N.A. (the "Initial
Trustee") are parties to an Indenture, dated as of February 1, 1993 (the
"Existing Indenture"), as supplemented by the first supplemental indenture among
the Company, the Initial Trustee and Fleet, dated as of February 1, 1996 (the
"First Supplemental Indenture" and together with the Existing Indenture, the
"Indenture"), pursuant to which the Company issued its 6.125% Notes Due 2006
(the "Notes");

     WHEREAS, the Board of Directors of the Company has determined that it is in
the best interests of the Company to authorize and approve the proposed
amendments to the Indenture solely with respect to the Notes (the "Proposed
Amendments");

     WHEREAS, Section 902 of the Indenture provides that the Company and the
Trustee may amend the Indenture and the Notes with the consent of the Holders of
not less than 66-2/3% in principal amount of the Notes outstanding affected by
such supplemental indenture;

     WHEREAS, the Company has distributed an Offer to Purchase and Consent
Solicitation Statement, dated July 19, 2004 (the "Statement"), and accompanying
Consent and Letter of Transmittal to the Holders of the Notes in connection with
the Proposed Amendments as described in the Solicitation Statement;

     WHEREAS, the Holders of not less than 66-2/3% in principal amount of the
Notes outstanding have approved the Proposed Amendments to the provisions of the
Indenture; and

     WHEREAS, the execution and delivery of this instrument have been duly
authorized and all conditions and requirements necessary to make this instrument
a valid and binding agreement have been duly performed and complied with;

     NOW, THEREFORE, for and in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which hereby are
acknowledged, it is mutually covenanted and agreed, for the equal proportionate
benefit of all Holders of the Notes, as follows:


ARTICLE 1. AMENDMENTS TO ARTICLE 1--DEFINITIONS AND OTHER PROVISIONS OF GENERAL
           APPLICATION

     Section 1.1. Upon the effective date of this Second Supplemental Indenture,
certain definitions in Section 101 of the Indenture shall be deemed deleted when
references to such definitions would be eliminated as a result of the amendments
described herein.


ARTICLE 2. AMENDMENTS TO ARTICLE 5--REMEDIES

     Section 2.1. Section 501(5) of the Indenture is hereby amended to read in
its entirety as set forth below:



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                  (5) intentionally omitted;


     Section 2.2. Section 501(6) of the Indenture is hereby amended to read in
its entirety as set forth below:


                  (6) intentionally omitted;


     Section 2.3. Section 515 of the Indenture is hereby amended to read in its
entirety as set forth below:


                  Section 515. Intentionally omitted.
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ARTICLE 3. AMENDMENTS TO ARTICLE 8--CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER
           OR LEASE

     Section 3.1. Section 801 of the Indenture is hereby amended to read in its
entirety as set forth below:


                  Section 801. Intentionally omitted.
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ARTICLE 4. AMENDMENTS TO ARTICLE 10--COVENANTS

     Section 4.1. Section 1006 of the Indenture is hereby amended to read in its
entirety as set forth below:


                  Section 1006. Intentionally omitted.
                                ---------------------


     Section 4.2. Section 1007 of the Indenture is hereby amended to read in its
entirety as set forth below:


                  Section 1007. Intentionally omitted.
                                ---------------------


     Section 4.3. Section 1008 of the Indenture is hereby amended to read in its
entirety as set forth below:


                  Section 1008. Intentionally omitted.
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     Section 4.4. Section 1009 of the Indenture is hereby amended to read in its
entirety as set forth below:


                  Section 1009. Intentionally omitted.
                                ---------------------


     Section 4.5. Section 1010 of the Indenture is hereby amended to read in its
entirety as set forth below:


                  Section 1010. Intentionally omitted.
                                ---------------------


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ARTICLE 5.        AMENDMENTS TO THE NOTES

     Section 5.1. The Notes include certain of the foregoing provisions from the
Indenture. Upon the effective date of this Second Supplemental Indenture, such
provisions from the Notes shall be deemed deleted or amended as applicable.


ARTICLE 6.        MISCELLANEOUS

     Section 6.1. All capitalized terms used and not defined herein shall have
the respective meanings assigned to them in the Indenture.

     Section 6.2. Upon execution and delivery of this Second Supplemental
Indenture, the terms and conditions of this Second Supplemental Indenture shall
be part of the terms and conditions of the Indenture for any and all purposes,
and all the terms and conditions of both shall be read together as though they
constitute one and the same instrument, except that in case of conflict, the
provisions of this Second Supplemental Indenture will control.

     Section 6.3. Notwithstanding an earlier execution date, the provisions of
this Second Supplemental Indenture shall not become operative until the time and
date upon which the Company notifies the depositary and tabulation agent for the
Notes, Deutsche Bank Trust Company Americas, that the Notes are accepted for
purchase pursuant to the Offer to Purchase and Consent Solicitation Statement
date July 19, 2004. The Company shall promptly notify the Trustee in writing
that this Second Supplemental Indenture has become operative.

     Section 6.4. Each of the Company and the Trustee hereby confirms and
reaffirms the Indenture in every particular except as amended and supplemented
by this Second Supplemental Indenture.

     Section 6.5. All covenants and agreements in this Second Supplemental
Indenture by the Company or the Trustee shall bind their respective successors
and assigns, whether so expressed or not.

     Section 6.6. In case any provisions in this Second Supplemental Indenture
shall be invalid, illegal or unenforceable, the validity, legality and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby.

     Section 6.7. Nothing in this Second Supplemental Indenture, express or
implied, shall give to any Person, other than the parties hereto and their
successors under the Indenture and the Holders of the Notes, any benefit or any
legal or equitable right, remedy or claim under the Indenture.

     Section 6.8. The parties may sign any number of copies of this Second
Supplemental Indenture. Each signed copy shall be an original, but all of them
together shall represent the same agreement. One signed copy is enough to prove
this Second Supplemental Indenture.

     Section 6.9. This Second Supplemental Indenture shall be governed by and
construed in accordance with the laws of the State of New York, as applied to
contracts made and performed within the State of New York, without regard to
principles of conflicts of law. Each of the parties hereto agrees to submit to
the jurisdiction of the courts of the State of New York in any action or
proceeding arising out of or relating to this Second Supplemental Indenture.


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     Section 6.10. All provisions of this Second Supplemental Indenture shall be
deemed to be incorporated in, and made a part of, the Indenture; and the
Indenture, as amended and supplemented by this Second Supplemental Indenture,
shall be read, taken and construed as one and the same instrument.


     Section 6.11. The Trustee has accepted the amendment of the Indenture
effected by this Second Supplemental Indenture and agrees to execute the trust
created by the Indenture as hereby amended, but only upon the terms and
conditions set forth in the Indenture, including the terms and provisions
defining and limiting the liabilities and responsibilities of the Trustee, and
without limiting the generality of the foregoing, the Trustee shall not be
responsible in any manner whatsoever for or in respect to (a) the validity or
sufficiency of this Second Supplemental Indenture or any of the terms or
provisions hereof, (b) the proper authorization hereof by the Company by
corporate action or otherwise, (c) the due execution hereof by the Company, (d)
the consequences (direct or indirect and whether deliberate inadvertent) of any
amendment herein provided for, and the Trustee makes no representation with
respect to any such matters and (e) the validity or sufficiency of the
solicitation or the consent solicitation materials or procedure in connection
therewith.


     Section 6.12. The provisions of this Second Supplemental Indenture are made
solely with respect to the 6.125% Notes due 2006 of the Company, and none of the
terms of this Second Supplemental Indenture shall apply to any other series of
Notes issued under the Indenture or the First Supplemental Indenture.


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     IN WITNESS WHEREOF, the parties hereto have caused this Second Supplemental
Indenture to be duly executed as of the date first written above.


                               CROMPTON CORPORATION


                               By:   /s/ John R. Jepsen
                                   -----------------------------------------
                                     Name:  John R. Jepsen
                                     Title: Vice President and Treasurer


                               U.S. BANK, National Association, as Trustee


                               By:   /s/ Michael M. Hopkins
                                   ---------------------------------------
                                     Name:  Michael M. Hopkins
                                     Title: Vice President