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                                                                   EXHIBIT 10.23

                             AMENDMENT TO AGREEMENT

         WHEREAS, CheMatch.com, Inc. (formerly known as PetroChemNet Holdings,
Inc.), hereinafter "PCN, CheMatch, or the Company" and E.I. duPont de Nemours
and Company, hereinafter "DuPont", entered into a certain Strategic Alliance
Agreement dated November 11, 1999; and

         WHEREAS, CheMatch and DuPont have agreed to certain amendments and
clarifications to such Strategic Alliance Agreement;

         NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, CheMatch and DuPont agree as
follows:

1.       Paragraph 2(b) of the Strategic Alliance Agreement is hereby deleted in
         its entirety and the following substituted therefor:

         (b)      DuPont will work with CheMatch to add those potential
                  customers agreed by the parties to the customers using the
                  CheMatch platform of CheMatch for trading products. For each
                  such customer up to a maximum of 20 customers, that completes
                  at least five (5) transactions with parties other than DuPont
                  on the CheMatch platform prior to December 31, 2000 at the
                  standard rates charged for the use of the CheMatch platform,
                  DuPont shall earn a commission of $100,000. In lieu of a cash
                  payment , DuPont will use such commission to purchase a number
                  of shares of Common Stock of CheMatch equal to such $100,000,
                  divided by the Fair Market Value per share of Common Stock.
                  Additionally, for each such customer that completes at least
                  four (4) transactions or transacts notional value equal to or
                  greater than $3,000,000 in a minimum of two (2) transactions
                  (including auctions or reverse auctions) with DuPont prior to
                  December 31, 2000, at the standard rates charged for the use
                  of the CheMatch platform, DuPont will earn a commission of
                  $50,000. In lieu of a cash payment, DuPont will use such
                  commission to purchase a number of shares of Common Stock of
                  CheMatch equal to such $50,000, divided by the Fair Market
                  Value per share of Common Stock. For the purposes of this
                  paragraph 2(b), "Fair Market Value" shall mean (i) the price
                  per share paid for the Series C Preferred Stock until the date
                  120 days from 1 December 1999, or (ii) thereafter, the per
                  share price based on the most recent transaction value or
                  appraisal, if CheMatch has not completed its initial public
                  offering, or if CheMatch has completed its initial public
                  offering, the closing price of CheMatch's Common Stock on the
                  date of the fourth trade or the date of the transacted
                  notional value is equal to or greater than $3,000,000 in a
                  minimum of two transactions meeting the conditions set forth
                  above. Provided that, in no event shall the commissions earned
                  pursuant to this paragraph exceed in the aggregate $2,000,000,
                  nor the total of Common Stock of CheMatch owned by DuPont
                  exceed 10% of the "fully diluted" common stock as described in
                  paragraph 2(c) below.

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2.       Except as amended hereby, the Strategic Alliance Agreement dated
         November 11, 1999 by and between CheMatch and DuPont remain in full
         force and effect.


ACCEPTED AND AGREED this 20th day of March, 2000.

CHEMATCH.COM, INC.                          E. I. DUPONT DENEMOURS AND CO.


By:   /s/ Fred B. Cook                      By:    /s/ S.A. Hamdan
   --------------------------------            ---------------------------------
Name:     Fred B. Cook                      Name:      S.A. Hamdan
Title:    Senior Vice President             Title:     Director