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                                                                   EXHIBIT 10.11



                       FIRST AMENDMENT TO LETTER AGREEMENT
                            DATED SEPTEMBER 29, 1999


     FIRST AMENDMENT TO LETTER AGREEMENT DATED SEPTEMBER 29, 1999 (this
"Amendment"), between International Specialty Products Inc., a Delaware
corporation (the "Company"), and Sunil Kumar ("Kumar").

                              W I T N E S S E T H :
                              - - - - - - - - - --

     WHEREAS, the Company entered into a Letter Agreement dated September 29,
1999 (the "Agreement") with Kumar;

         WHEREAS, capitalized terms used herein and not otherwise defined shall
have the same meaning as such terms are used in the Agreement; and

         WHEREAS, the Company and Kumar desire to amend the Agreement and the
Note to reflect a change in the terms applicable to the payment of interest
thereunder.

         NOW, THEREFORE, in consideration of the foregoing promises and the
following promises, and for other good and valuable consideration, the receipt
and adequacy of which are hereby acknowledged, the parties agree as follows:

         SECTION 1.        AMENDMENTS TO THE AGREEMENT

     1.1 The third sentence of Section 2(a) of the Agreement shall be amended in
its entirety to read as follows:

         "The Note shall bear interest on the unpaid principal amount
         outstanding, from the date thereof until the Note is paid in full or
         cancelled as provided in paragraph 2(g) hereof, at a rate of six
         percent (6%) per annum payable as follows: (i) three percent (3%) shall
         be payable annually in arrears on February 15 of each year, commencing
         on February 15, 2000 (each a "Mandatory Annual Interest Payment"), and
         (ii) the remaining three percent (3%) shall continue to accrue and
         shall be payable in arrears on the earlier of the stated maturity of
         the Note or the date on which the outstanding principal amount of the
         Note is declared to be due and payable (as such amount may accrue from
         time to time, "Deferred Interest"). "

     1.2 The first sentence of Section 2(g)(i) of the Agreement shall be amended
in its entirety to read as follows:

     "(i) If, during the period commencing on the date hereof and ending at the
     close of business on each Installment Payment Date, you remain continuously
     employed by the Company or any of its subsidiaries, the

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     principal amount of the Loan due and payable on such Installment Payment
     Date shall be forgiven (but not the Deferred Interest), so that if, during
     the period commencing on the date hereof and ending at the close of
     business on January 11, 2004, you have remained continuously employed by
     the Company or any of its subsidiaries, the Loan and the Note shall be
     cancelled and discharged in full; provided that all Mandatory Annual
     Interest Payments and Deferred Interest due on the Note shall have been
     paid."

         SECTION 2.        AMENDMENTS TO THE NOTE

         2.1 The parties hereto agree that the Note is hereby amended to reflect
the terms of this Amendment and, at the option of the Company, Kumar shall
deliver to the Company for cancellation the Note and shall execute a new note in
favor of the Company to reflect such changes or execute an amendment thereto
prepared by the Company, and in each case shall promptly deliver the same to the
Company.

         SECTION 3.        MISCELLANEOUS

         3.1 EXECUTION. This Amendment may be executed in counterparts and by
the different parties hereto on separate counterparts, each of which, when so
executed and delivered, shall be an original, but all such counterparts shall
together constitute but on and the same instrument.

         3.2 GOVERNING LAW. This Amendment shall be governed by, and construed
in accordance with, the laws of the State of New Jersey and for all purposes
shall be enforced in accordance with the internal laws of that state without
regard to the principles of conflicts of law.

         3.3 FULL FORCE AND EFFECT. As amended hereby, the Agreement remains in
full force and effect in accordance with its terms and all future references to
the Agreement or the Note shall mean the Agreement and the Note, in each case as
amended hereby.

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and delivered as of the 30th day of November 2000.


                                    INTERNATIONAL SPECIALTY PRODUCTS INC.


                                    By: /S/  SAMUEL J. HEYMAN
                                        -----------------------
                                    Name:  Samuel J. Heyman
                                    Title: Chairman


                                        /S/  SUNIL KUMAR
                                        -----------------------
                                        Sunil Kumar


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