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                                                                    EXHIBIT 10.4

                              AMENDED AND RESTATED
                              REVOLVING CREDIT NOTE

$12,500,000                                                        March 5, 2003

     This Amended and Restated Revolving Credit Note is executed and delivered
under and pursuant to the terms of that certain Fourth Amended and Restated
Revolving Credit and Security Agreement dated as December 26, 2001 (as amended,
by that certain Amendment to Fourth Amended and Restated Revolving Credit and
Security Agreement dated February 4, 2002 and that certain Second Amendment to
Fourth Amended and Restated Revolving Credit Security Agreement dated the date
hereof and as may be further amended, supplemented or modified from time to
time, collectively supplemented or modified from time to time, the "Credit
Agreement") by and among RADNOR HOLDINGS CORPORATION, WINCUP HOLDINGS, INC.,
RADNOR CHEMICAL CORPORATION, STYROCHEM U.S., LTD., RADNOR DELAWARE II, INC.,
WINCUP TEXAS, LTD., STYROCHEM DELAWARE, INC., STYROCHEM GP, L.L.C., STYROCHEM
LP, L.L.C., WINCUP GP, L.L.C. AND WINCUP LP, L.L.C. (each, a "Maker" and jointly
and severally, the "Makers"), the financial institutions named therein and the
financial institutions which hereafter become a party thereto (collectively, the
"Lenders"), PNC BANK, NATIONAL ASSOCIATION as lead arranger and administrative
agent for the Lenders (in such capacity, the "Agent"), and FLEET CAPITAL
CORPORATION as documentation agent (in such capacity as "Documentation Agent").
Capitalized terms not otherwise defined herein shall have the meanings ascribed
thereto in the Credit Agreement.

     FOR VALUE RECEIVED, the undersigned Makers, jointly and severally, hereby
promise to pay to the order of LASALLE BUSINESS CREDIT, LLC ("Lender"), at the
offices of Agent, in such coin or currency of the United States which shall be
legal tender in payment of all debts and dues, public and private, at the time
of payment, the principal sum of TWELVE MILLION FIVE HUNDRED THOUSAND DOLLARS
($12,500,000), or such lesser sum which then represents the aggregate unpaid
principal balance of Lender's Commitment Percentage of the Revolving Advances,
together with interest from and after the date hereof on the unpaid principal
balance outstanding at the applicable per annum rate(s) set forth in the Credit
Agreement. The actual amount due and owing from time to time hereunder shall be
evidenced by Agent's records of receipts and disbursements with respect to the
Revolving Advances, which shall be prima facie evidence of the unpaid balance
thereof.

     This Amended and Restated Revolving Credit Note ("Note") is the Note
referred to in, and is issued pursuant to, the Credit Agreement, and is subject
to all the terms and conditions of and entitled to all of the benefits and
security of the Credit Agreement. All capitalized terms used herein, unless
otherwise specifically defined in this Note, shall have the meanings ascribed to
them in the Credit Agreement.

     Interest shall accrue at the rates set forth (including, if applicable, a
default rate), and shall be computed in the manner provided, in Article III of
the Credit Agreement. In no event whatsoever shall interest and other charges
charged hereunder exceed the highest rate

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permissible under law. In the event interest and other charges as computed
hereunder would otherwise exceed the highest rate permitted under law, such
excess amount shall be first applied to any unpaid principal balance owed by
Makers, and if the then remaining excess amount is greater than the previously
unpaid principal balance, Lender shall promptly refund such excess amount to
Makers and the provisions hereof shall be deemed amended to provide for such
permissible rate.

     Interest shall be charged and payable on the outstanding balance hereunder
at the applicable rate provided in the Credit Agreement notwithstanding and even
following the occurrence of any Event of Default, acceleration, judgment,
bankruptcy or reorganization proceedings or any other event or occurrence.

     The principal amount of this Note, and also the accrued interest thereon,
shall be due and payable in the amounts, on the dates and in the manner set
forth in the Credit Agreement.

     This Note shall evidence the unconditional obligation of Makers to repay to
Lender the outstanding balance of Revolving Advances made to Makers by Lender,
with interest thereon and all fees, costs and expenses in connection therewith.

     Reference is made to the Credit Agreement for provisions concerning
prepayment and acceleration of the outstanding balance of the obligations of
each Maker under this Note. This Note is secured by and shall have the benefits
of the Collateral described in the Credit Agreement.

     Upon the occurrence of an Event of Default, Lender shall have all of the
rights and remedies set forth in Article 11 of the Credit Agreement. The rights
and options of Lender under this Note shall be enforced by Agent under the terms
and conditions hereof and of the Credit Agreement.

     Time is of the essence in the performance of this Note. To the fullest
extent permitted by applicable law, each Maker, for itself and its legal
representatives, successors and assigns, expressly waives presentment, demand,
protest, notice of dishonor, notice of non-payment, notice of maturity, notice
of protest, presentment for the purpose of accelerating maturity, diligence in
collection, and the benefit of any exemption or insolvency laws.

     No delay or failure on the part of Agent or Lender in the exercise of any
right or remedy hereunder shall operate as a waiver thereof, nor as an
acquiescence in any default, nor shall any single or partial exercise by Agent
or Lender of any right or remedy preclude any other right or remedy. Agent, at
its option, may enforce its rights against any collateral securing this Note
without enforcing its rights against any Maker or any Borrower, any guarantor of
the indebtedness evidenced hereby or any other property of any Maker or any
Borrower. Makers agree that, without releasing or impairing Makers' liability
hereunder, Agent may at any time release, surrender, substitute or exchange any
collateral securing this Note and may at any time release any party primarily or
secondarily liable for the indebtedness evidenced by this Note.

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     This Note shall be construed and governed by the laws of the Commonwealth
of Pennsylvania without reference to its conflicts of laws rules. The provisions
of this Note are severable and the invalidity or unenforceability of any
provision shall not alter or impair the remaining provisions of this Note. No
modification hereof shall be binding or enforceable against Lender unless
approved in writing by Lender.

     EACH MAKER HEREBY EXPRESSLY WAIVES ANY RIGHT TO TRIAL BY JURY OF ANY CLAIM,
DEMAND, ACTION OR CAUSE OF ACTION (A) ARISING UNDER THIS NOTE OR ANY OTHER
INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH,
OR (B) IN ANY WAY CONNECTED WITH OR RELATED OR INCIDENTAL TO THE DEALINGS OF
MAKER, LENDER AND/OR AGENT OR ANY OF THEM WITH RESPECT TO THIS NOTE OR ANY OTHER
INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH,
OR THE TRANSACTIONS RELATED HERETO OR THERETO IN EACH CASE WHETHER NOW EXISTING
OR HEREAFTER ARISING, AND WHETHER SOUNDING IN CONTRACT OR TORT OR OTHERWISE AND
EACH MAKER HEREBY CONSENTS THAT ANY SUCH CLAIM, DEMAND, ACTION OR CAUSE OF
ACTION SHALL BE DECIDED BY COURT TRIAL WITHOUT A JURY, AND THAT MAKER, AGENT
AND/OR LENDER MAY FILE AN ORIGINAL COUNTERPART OR A COPY OF THIS SECTION WITH
ANY COURT AS WRITTEN EVIDENCE OF THE CONSENT OF EACH MAKER TO THE WAIVER OF ITS
RIGHT TO TRIAL BY JURY.

     Any judicial proceeding brought by or against any Maker with respect to
this Note or any related agreement may be brought in any court of competent
jurisdiction located in the Commonwealth of Pennsylvania, and, by execution and
delivery of this Note, each Maker accepts for itself and in connection with its
properties, generally and unconditionally, the non-exclusive jurisdiction of the
aforesaid courts, and irrevocably agrees to be bound by any judgment rendered
thereby in connection with this Note. Each Maker hereby waives personal service
of any and all process upon it and consents that all such service of process may
be made upon it in the manner provided for in Section 15.1 of the Credit
Agreement. Each Maker waives any objection to jurisdiction and venue of any
action instituted hereunder and shall not assert any defense based on lack of
jurisdiction or venue or based upon forum non conveniens. Any judicial
proceeding by any Maker against Agent or Lender involving, directly or
indirectly, any matter or claim in any way arising out of, related to or
connected with this Note or any related agreement, shall be brought only in a
federal or state court located in the County of Philadelphia, Commonwealth of
Pennsylvania.

     This Note together with other promissory note executed the date hereof and
delivered in connection with and pursuant to the terms of the Credit Agreement
amend and restate, but do not extinguish the obligations evidenced by that
certain Amended and Restated Revolving Credit Note issued by Makers in favor of
Lender in the original principal amount of $35,000,000 pursuant to the terms of
that certain Credit Agreement dated February 4, 2002.

                         [Signatures begin on next page]

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     IN WITNESS WHEREOF, Makers, intending to be legally bound, have caused this
Note to be duly executed and delivered on the date first above written.

                           WINCUP HOLDINGS, INC.

                           By:/s/ R. Radcliffe Hastings
                               ------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

                           RADNOR CHEMICAL CORPORATION

                           By:/s/ R. Radcliffe Hastings
                              -------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

                           STYROCHEM U.S., LTD.
                           By: StyroChem GP, LLC, its General Partner
                             By: Radnor Chemical Corporation, its Sole Member

                           By:/s/ R. Radcliffe Hastings
                              -------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

                           RADNOR HOLDINGS CORPORATION

                           By:/s/ R. Radcliffe Hastings
                              -------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

                           RADNOR DELAWARE II, INC.

                           By:/s/ R. Radcliffe Hastings
                              -------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

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                           STYROCHEM DELAWARE, INC.

                           By:/s/ R. Radcliffe Hastings
                              --------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

                           WINCUP TEXAS, LTD.
                           By: WinCup GP, LLC, its General Partner
                              By: WinCup Holdings, Inc., its Sole Member

                           By:/s/ R. Radcliffe Hastings
                              --------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

                           STYROCHEM GP, L.L.C.
                           By: Radnor Chemical Corporation, its Sole Member

                           By:/s/ R. Radcliffe Hastings
                              --------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

                           STYROCHEM LP, L.L.C.
                           By: Radnor Chemical Corporation, its Sole Member

                           By:/s/ R. Radcliffe Hastings
                              --------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

                           WINCUP GP, L.L.C.
                           By: WinCup Holdings, Inc. its Sole Member

                           By:/s/ R. Radcliffe Hastings
                              --------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

                           WINCUP LP, L.L.C.
                           By: WinCup Holdings, Inc. its Sole Member

                           By:/s/ R. Radcliffe Hastings
                              --------------------------------------------------
                           R. Radcliffe Hastings, Sr. Vice President, Treasurer

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