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                                                                   Exhibit 10.21


                             AMENDED AND RESTATED
                          U.S. REVOLVING CREDIT NOTE


$16,000,000.00                                                 December 29, 1999

     This Amended and Restated U.S. Revolving Credit Note is executed and
delivered under and pursuant to the terms of that certain Third Amended and
Restated Revolving Credit and Security Agreement dated as of the date hereof (as
amended, supplemented or modified from time to time, the "Loan Agreement") by
and among WinCup Holdings, Inc., Radnor Chemical Corporation, Radnor Holdings
Corporation, Radnor Delaware, Inc., StyroChem U.S., Ltd., Styrochem Delaware,
Inc., and Wincup Texas, Ltd. (each, a "U.S. Borrower" and jointly and severally,
the "U.S. Borrowers") and StyroChem Europe (The Netherlands) B.V., StyroChem
Finland OY, ThermiSol Denmark A/S, ThermiSol Finland OY and ThermiSol Sweden AB
(each a "European Borrower" and jointly and severally, the "European Borrowers";
the European Borrowers together with the U.S. Borrowers each, a "Borrower" and
collectively, the "Borrowers"), the financial institutions named therein and the
financial institutions which hereafter become a party thereto (collectively, the
"Lenders") and Bank of America, N.A. as administrative and collateral agent for
the Lenders (in such capacity, the "Agent").  Capitalized terms not otherwise
defined herein shall have the meanings ascribed thereto in the Loan Agreement.

     FOR VALUE RECEIVED, the U.S. Borrowers jointly and severally hereby promise
to pay to the order of FIRST UNION NATIONAL BANK (the "Bank"), at Agent's
offices located at 101 N. Tryon Street, Charlotte, North Carolina 28255 or at
such other place as the holder may from time to time designate to Borrower in
writing:

     (i)  the principal sum of SIXTEEN MILLION DOLLARS ($16,000,000.00) or, if
different from such amount, the unpaid principal balance of the Bank's
Commitment Percentage of U.S. Revolving Advances as may be due and owing under
the Loan Agreement, payable in accordance with the provisions of the Loan
Agreement, subject to acceleration upon the occurrence of an Event of Default
under the Loan Agreement, termination of the Loan Agreement pursuant to the
terms thereof or repayment as required by the Loan Agreement; and

     (ii) interest in the principal amount of this Note from time to time
outstanding until such principal amount is paid in full at such interest rates
and at such times as are specified in the Loan Agreement.  In no event, however,
shall interest hereunder exceed the maximum interest rate permitted by law.
Upon and after the occurrence of an Event of Default, and during the
continuation thereof, interest shall be payable at the Default Rate.

     This Note is one of the U.S. Revolving Credit Notes referred to in the Loan
Agreement and is secured, inter alia, by the liens granted pursuant to the Loan
                          ----------
Agreement and the Other Documents, is entitled to the benefits of the Loan
Agreement and the Other Documents and is subject to all of the agreements, terms
and conditions therein contained.
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     This note may be prepaid, in whole or in part, on the terms and conditions
set forth in the Loan Agreement.

     This Note shall be construed and enforced in accordance with the laws of
the State of New York.

     Each U.S. Borrower expressly waives any presentment, demand, protest,
notice of protest, or notice of any kind except as expressly provided in the
Loan Agreement.

     This Note, together with the other U.S. Revolving Credit Notes executed and
delivered under and pursuant to the terms of the Loan Agreement, amends and
restates in its entirety, and is issued in full substitution and replacement for
(but not satisfaction of), each Revolving Credit Note executed and delivered
under and pursuant to the terms of the Existing Loan Agreement.


     IN WITNESS WHEREOF, I have hereunto set my hand this 29th day of December,
1999.


                                    WINCUP HOLDINGS, INC.
                                    RADNOR CHEMICAL CORPORATION
                                    RADNOR HOLDINGS CORPORATION
                                    RADNOR DELAWARE, INC.
                                    STYROCHEM U.S., LTD.
                                      By: StyroChem GP, L.L.C., its general
                                          partner
                                    STYROCHEM DELAWARE, INC.
                                    WINCUP TEXAS, LTD.
                                      By: WinCup GP, L.L.C., its general
                                          partner
                                    By:/s/ R. Radcliffe Hastings
                                       __________________________
                                    Name:R. Radcliffe Hastings
                                         _____________________
                                    Title:Senior Vice President of each of the
                                          foregoing (or, if applicable, its
                                          general partner)

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