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                                                                   EXHIBIT 10.52


              AMENDMENT TO CONVERTIBLE DEBENTURE PURCHASE AGREEMENT

         AMENDMENT TO CONVERTIBLE DEBENTURE PURCHASE AGREEMENT ("AGREEMENT")
dated as of November ___, 2001 between the U.S. Plastic Lumber Corp. (the
"Company"), and Stout Partnership, a New Jersey Partnership (the "INVESTORS")

                              W I T N E S S E T H:

         WHEREAS, U.S. Plastic Lumber Corp. (the "Company") and the Investors
have heretofore entered into a Convertible Debenture Agreement on December 1,
2000 in the aggregate amount of $5,000,000 which was subsequently amended on
March 15, 2001; and

         WHEREAS, the Company and the Investors are desirous of amending the
Convertible Debenture Agreement to further extend the due date of the
debentures; and

         WHEREAS, the Investors are major shareholders in the Company and derive
economic benefit from the success of the Company, and

         WHEREAS, the Investors are willing to execute this Amendment;

         NOW, THEREFORE, in consideration of the foregoing premises and the
covenants contained herein and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
agree as follows:

1.       MATURITY DATE. The Maturity Date as defined in the Debenture shall be
         amended to be January 1, 2003.

2.       CONSIDERATION FOR MATURITY DATE EXTENSION. The parties agree to the
         following terms and conditions:

         (a) The Company agrees that upon repayment of the principal, the
         Company shall pay Holder a sum equal to 115% of the original principal
         amount.

         (b) The Company shall issue to the Holder upon the execution of this
         Amendment Warrants to purchase 100,000 shares of the Company's Common
         Stock, par value $.0001, at an exercise price of $0.50 per share. The
         Warrant shall have a term of five years.

3.       MISCELLANEOUS. All remaining terms of the Convertible Debenture
         Purchase Agreement and related agreements between the Company and
         Investors are unchanged and shall remain in full force and effect. This
         Agreement shall be governed by and construed and enforced in accordance
         with the laws of the State of Florida. This Agreement may be executed
         in two or more counterparts, all of which shall be considered on and
         the same agreement, it being understood that all parties need not sign
         the same counterpart.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
         executed on the date first written above.

                                              STOUT PARTNERSHIP

                                              --------------------------
                                              Gary J. Ziegler
                                              Title: Managing Partner

                                              U.S. Plastic Lumber Corp.

                                              ----------------------------
                                              Bruce C. Rosetto, Secretary