EXHIBIT 3.1R


                            ARTICLES OF INCORPORATION
                                       OF
                             CROMPTON MONOCHEM, INC.

        The undersigned, acting pursuant to the Business Corporation Law of the
State of Louisiana, adopts the following Articles of Incorporation:

                                    ARTICLE I
                                      NAME

        The name of the corporation (the "Corporation") is Crompton Monochem,
Inc.

                                   ARTICLE II
                                     PURPOSE

        The purpose of the Corporation is to engage in any lawful activity for
which corporations may be formed under the Louisiana Business Corporation Law.

                                   ARTICLE III
                                     CAPITAL

        The Corporation has authority to issue an aggregate of 1,000 shares of
capital stock, all of which shall be designated common stock having a par value
of $0.01 per share.

                                   ARTICLE IV
                               DIRECTORS' PROXIES

        Any director absent from a meeting of the Board of Directors or any
committee thereof may be represented by any other director or shareholder, who
may cast the vote of the absent director according to the written instructions,
general or special, of the absent director.

                                    ARTICLE V
                   LIMITATION OF LIABILITY AND INDEMNIFICATION

        A.   No director or officer of the Corporation shall be liable to the
Corporation or to its shareholders for monetary damages for breach of his
fiduciary duty as a director or officer, provided that the foregoing provision
shall not eliminate or limit the liability of a director or officer for (1) any
breach of his duty of loyalty to the Corporation or its shareholders, (2) acts
or omissions not in good faith or that involve intentional misconduct or a
knowing violation of law, (3) liability for unlawful distributions of the
Corporation's assets to, or redemption or repurchase of the Corporation's shares
from, shareholders of the Corporation, under and to the extent provided in La.
R.S. Section 12:92D, or (4) any transaction from which he derived an improper
personal benefit.



        B.   The Corporation shall indemnify to the fullest extent from time to
time permitted by law, any officer or director of the Corporation against any
expenses and costs, including attorneys' fees, actually and reasonably incurred
by him in connection with any threatened, pending or completed claim, action,
suit or proceeding, whether criminal, civil, administrative or investigative,
against such person or as to which such person is involved solely as a witness
or person required to give evidence because he is an officer or director of the
Corporation.

        C.   The Board of Directors may (1) cause the Corporation to enter into
contracts with directors and officers providing for the limitation of liability
and indemnification set forth in this Article to the fullest extent permitted by
law, (2) adopt by-laws or resolutions providing for indemnification of directors
and officers of the Corporation and other persons, and (3) cause the Corporation
to exercise the powers set forth in La. R.S. Section 12:83F, notwithstanding
that some or all of the members of the Board of Directors acting with respect to
the foregoing may be parties to such contracts, or beneficiaries of such by-laws
or resolutions or the exercise of such powers.

        D.   Notwithstanding any other provision of these Articles of
Incorporation, the affirmative vote of at least 80% of the total voting power
shall be required to amend or repeal this Article. Neither the amendment nor
repeal of this Article, nor the adoption of any provision of these Articles of
Incorporation inconsistent with this Article, shall eliminate or reduce the
protection afforded by this Article to a director or officer of the Corporation
with respect to any action or inaction occurring prior to the time of such
amendment, repeal or adoption.

                                   ARTICLE VI
                                    REVERSION

        Cash, property or share dividends, shares issuable to shareholders in
connection with a reclassification of stock, and the redemption price of
redeemed shares, which are not claimed by the shareholders entitled thereto
within eighteen months after the dividend or redemption price becomes payable or
the shares become issuable, despite reasonable efforts by the Corporation to pay
the dividend or redemption price or deliver the certificates for the shares to
such shareholders within such time, shall, at the expiration of such time,
revert in full ownership to the Corporation, and the Corporation's obligation to
pay such dividend or redemption price or issue such shares, as the case may be,
shall thereupon cease; provided that the Board of Directors may, at any time,
for any reason satisfactory to it, but need not, authorize (a) payment of the
amount of any cash or property dividend or redemption price or (b) issuance of
any shares, ownership of which has reverted to the Corporation pursuant to the
provisions of this Article, to the person or entity who or which would be
entitled thereto had such reversion not occurred.

                                   ARTICLE VII
                                  INCORPORATOR

        The name and post office address of the Incorporator is:

                              Philip de V. Claverie
                              Phelps Dunbar, L.L.P.
                          365 Canal Street, Suite 2000
                          New Orleans, Louisiana 70130

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        These Articles of Incorporation are dated November 12, 2001.


                                                  /s/ Philip de V. Claverie
                                              ----------------------------------
                                                      Philip de V. Claverie
                                                          Incorporator

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