<PAGE>   1
KYZEN CORPORATION
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PART III (Continued)

     Exhibit 2.1           Articles of Merger

                               ARTICLES OF MERGER
                                       OF
                                KYZEN CORPORATION
                              (A UTAH CORPORATION)
                                      INTO
                          KYZEN ACQUISITION CORPORATION
                            (A TENNESSEE CORPORATION)


         Pursuant to Sections 48-21-105 and 48-21-107 of the Tennessee Business
Corporation Act, Kyzen Corporation, a Utah corporation ("Kyzen"), and Kyzen
Acquisition Corporation, a Tennessee corporation and wholly-owned subsidiary of
Kyzen ("KAC"), hereby adopt the following Articles of Merger:

         1. The Plan of Merger is attached hereto as Exhibit A and incorporated
herein by reference. The surviving corporation is KAC, a Tennessee corporation

         2. As to KAC, shareholder approval is not required. The Plan of Merger
was adopted by its Board of Directors on April 28, 1999.

         3. As to Kyzen, there are no voting groups other than the holders of
Class A Common Stock and the Plan of Merger was approved by the affirmative vote
of the majority of all of the votes entitled to be cast at the shareholders'
annual meeting held on April 28, 1999.

         4. As to Kyzen, the Plan of Merger and the performance of its terms
were duly authorized by all action required by the laws of the State of Utah and
by the Articles of Incorporation of Kyzen.

         5. The Plan of Merger shall be effective upon the later of the filing
of the Articles of Merger with the Secretary of State of Utah and the filing of
Articles of Merger with the Secretary of State of Tennessee.


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KYZEN CORPORATION
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PART III (Continued)

         IN WITNESS WHEREOF, each of the undersigned corporations has duly
caused these Articles of Merger to be executed by their respective duly
authorized officers as of this 25th day of May, 1999.



                                        KYZEN CORPORATION


                                        By: /s/ Kyle J. Doyel
                                            -----------------------------------
                                            Kyle J. Doyel, President



                                        KYZEN ACQUISITION
                                        CORPORATION


                                        By: /s/ Kyle J. Doyel
                                            -----------------------------------
                                            Kyle J. Doyel, President




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KYZEN CORPORATION
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PART III (Continued)

                                    EXHIBIT A

                                 PLAN OF MERGER


         WHEREAS, Kyzen Corporation ("Kyzen") is a corporation duly organized
and validly existing under the laws of the State of Utah;

         WHEREAS, Kyzen Acquisition Corporation ("KAC") is a corporation duly
organized and validly existing under the laws of the State of Tennessee and a
wholly-owned subsidiary of Kyzen;

         WHEREAS, the Boards of Directors of Kyzen and KAC have each determined
that it is advisable that Kyzen merge with and into KAC upon the terms and
conditions provided herein (the "Merger"); and

         WHEREAS, the Boards of Directors of Kyzen and KAC have approved this
Plan of Merger between Kyzen and KAC.

         NOW, THEREFORE, Kyzen and KAC hereby agree to merge into a single
corporation as follows:

         FIRST: Pursuant to this Plan of Merger, Kyzen shall be merged with and
into KAC and the separate corporate existence of Kyzen shall thereupon cease
(the "Merger"). KAC shall be the surviving corporation (the "Surviving
Corporation") and shall retain its corporate identity and succeed to all of the
rights, assets, liabilities and obligations of KAC and Kyzen.

         SECOND: The Merger shall become effective on the later of the filing of
Articles of Merger with the Secretary of State of Tennessee and the filing of
Articles of Merger with the Secretary of State of Utah, such time being
hereinafter referred to as the "Effective Time."

         THIRD: (a) KAC Stock. At the Effective Time, each share of Common
Stock, $.01 par value per share, of KAC (the "KAC Common Stock") issued and
outstanding immediately prior to the Effective Time shall automatically be
redeemed by the Surviving Corporation and, upon payment to the former holders
thereof, shall have no further rights or represent any further claim against the
Surviving Corporation.

         (b)      Kyzen Securities. (i) At the Effective Time, each share of
Common Stock, $.01 par value per share, of Kyzen (the "Kyzen Common Stock"),
issued and outstanding immediately prior to the Effective Time, other than
shares to be canceled pursuant to subparagraph (b)(iii) hereof below, by virtue
of the Merger and without any action on the part of the holder thereof, shall
automatically be converted into the right to receive one fully paid and
non-assessable share of the KAC Common Stock. At the Effective Time, no shares
of Kyzen Common Stock shall be outstanding and all such shares shall
automatically be canceled and returned and shall cease to exist.

                  (ii)     As a result of the Merger, each certificate nominally
representing shares of Kyzen Common Stock shall for all purposes be deemed to
evidence the ownership of a like number of shares of KAC Common Stock. The
holders of certificates of Kyzen Common Stock shall not be required immediately
to surrender the certificates in exchange for certificates of KAC Common Stock
but, as certificates nominally representing shares of Kyzen Common Stock are
surrendered for transfer, KAC will cause to be issued certificates for a like
number of shares of KAC Common Stock.


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KYZEN CORPORATION
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PART III (Continued)

                   (iii)    Each share of Kyzen Common Stock issued and held in
Kyzen's treasury at the Effective Time shall, by virtue of the Merger, cease to
be outstanding and shall automatically be canceled and retired and shall cease
to exist without payment of any consideration therefor.

                   (iv) As a result of the Merger, each outstanding warrant to
purchase one share of Kyzen Common Stock (each a "Kyzen Warrant"), whether or
not then vested or exercisable, will automatically be converted into a warrant
to purchase one share of KAC Common Stock (each a "KAC Warrant"). The holders of
Kyzen Warrant certificates shall not be required immediately to surrender the
certificates in exchange for certificates of KAC Warrants but, as certificates
nominally representing Kyzen Warrants are surrendered for transfer, KAC will
cause to be issued certificates for a like number of KAC Warrants.

                  (v)      As a result of the Merger, each outstanding option to
purchase one share of Kyzen Common Stock (each a "Kyzen Option"), whether or not
then vested or exercisable, will automatically be converted into an option to
purchase one share of KAC Common Stock (each a "KAC Option") on the same terms
and conditions. The holders of Kyzen Options shall not be required immediately
to surrender their option agreements in exchange for option agreements for KAC
Options.

                  (vi)     As a result of the Merger, each preferred share
purchase right issued with each share of Kyzen Common Stock and representing the
right to purchase 1/100th of a share of Kyzen's Series A Junior Participating
Preferred Stock will automatically be converted into one preferred share
purchase right representing the right to purchase 1/100th of a share of KAC's
Series A Junior Participating Preferred Stock, which will have identical rights
and preferences as Kyzen's Series A Junior Participating Preferred Stock.

         FOURTH: The Charter of KAC in effect immediately prior to the Effective
Time shall be the Charter of the Surviving Corporation, until duly amended in
accordance with applicable law; provided, however, Article 1 shall hereby be
deleted in its entirety and replaced with the following:

         1.       Name. The name of the corporation is Kyzen Corporation.

         FIFTH: The Bylaws of KAC in effect immediately prior to the Effective
Time shall be the Bylaws of the Surviving Corporation, until duly amended in
accordance with applicable law.

         SIXTH: The members of the board of directors and the officers of Kyzen
immediately prior to the Effective Time shall be the members of the board of
directors and the officers, respectively, of the Surviving Corporation, until
their respective successors are elected and qualified.

         SEVENTH: KAC agrees that it may be served with process in Tennessee in
any proceeding for enforcement of any obligation of Kyzen as well as for the
enforcement of any obligation of KAC arising from the Merger.

         EIGHTH: This Plan of Merger may be terminated and abandoned by action
of the board of directors of Kyzen at any time prior to the Effective Time,
whether before or after approval by the shareholders of the two corporate
parties hereto.


Dated: May 25, 1999




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