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                                                                 Exhibit 10.14a




                      AMENDMENT TO STOCKHOLDERS AGREEMENT
                      -----------------------------------


         This Amendment is made as of September 30, 1997 by and among Unifrax
Corporation, a Delaware corporation, (the "Company"), BP Exploration (Alaska)
Inc., a Delaware corporation, ("BP") and Unifrax Holding Co., a Delaware
corporation, (the "Buyer").

         WHEREAS, the Company, BP and the Buyer are parties to the Stockholders
Agreement dated as of October 30, 1996 (the "Agreement"); and

         WHEREAS, the Company, BP and the Buyer desire to amend the Agreement
as set forth in this Amendment due to the Company's recent authorization of
preferred stock and proposal to issue shares of such preferred stock to BP and
the Buyer.

         NOW, THEREFORE, in consideration of the mutual covenants contained in
this Amendment, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties to this Amendment
hereby agree as follows:

         1.   The definition of "BP Shares" as set forth in Section 1 of the
Agreement is amended to read, in its entirety, as follows:

              "BP Shares" means, collectively, all shares of Common Stock and
              Preferred Stock owned by BP or its Affiliates.

         2.   The definition of "Effective Percentage" as set forth in Section 1
of the Agreement is amended to read, in its entirety, as follows:

              "Effective Percentage" means the number of shares of Common Stock
              and Underlying Common Stock owned by BP divided by the total
              number of outstanding shares of Common Stock and Underlying
              Common Stock on a fully-diluted basis.

         3.   The definition of "Other Equity" as set forth in Section 1 of the
Agreement is amended to read, in its entirety, as follows:

              "Other Equity" means equity securities of the Company (other than
              Common Stock and Preferred Stock) and any options, warrants or
              other rights to acquire, or convertible into or exchangeable for,
              Common Stock, Preferred Stock or other equity securities of the
              Company.

         4.   The following definition is added to Section 1 of the Agreement:



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                "Preferred Stock" means, collectively, the preferred stock of
                the Company having a par value of $.01 per share, the
                relative rights, preferences and limitations of which are set
                forth in the Certificate of Amendment of Certificate of
                Incorporation of the Company, dated April 21, 1997.

         5.     The definition of "Public Offering" as set forth in Section 1 of
the Agreement is amended to read, in its entirety, as follows:

                "Public Offering" means any sale of Common Stock or Preferred
                Stock to the public pursuant to any offering registered under
                the Securities Act.

         6.     The definition of "Underlying Common Stock" as set forth
in Section 1 of the Agreement is amended to read, in its entirety, as follows:

                "Underlying Common Stock" means the Common Stock issued or
                issuable pursuant to the Preferred Stock or other securities
                containing granted options, conversion rights or other rights
                to acquire any shares of Common Stock.

         7.     The first sentence of Section 3(a) of the Agreement is amended 
to read, in its entirety, as follows:

                 Except for (i) the issuance of shares of Common Stock
                 representing, on a fully diluted basis, not more than seven
                 percent (7%) of the Company's total Common Stock, pursuant to
                 a Company Management Option Plan, or (ii) in connection with
                 a Public Offering, or (iii) the issuance of Common Stock in
                 connection with the acquisition of, or a merger with, another
                 corporation or business, or (iv) the issuance of shares of
                 Common Stock as a dividend on the outstanding Common Stock
                 that would not, after giving effect to the issuance of such
                 shares, affect the Effective Percentage, or (v) the original
                 issuance of not more than 166.67 shares of Preferred Stock to
                 BP prior to November 10, 1997, or (vi) the original issuance
                 of not more than 1,500 shares of Preferred Stock to Buyer
                 prior to November 10, 1997, or (vii) the issuance of shares
                 of Common Stock in connection with a conversion of shares of
                 Preferred Stock into shares of Common Stock, if the Company
                 desires to sell or otherwise issue any shares of Common
                 Stock, any shares of Preferred Stock or any securities
                 containing options or rights to acquire any shares of


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                Common Stock or Preferred Stock, the Company shall first offer
                to sell to BP a portion of such stock or securities equal to
                the Effective Percentage.

           8.   Section 4(b) of the Agreement is amended to read, in its
entirety, as follows:

                Within thirty (30) days after its receipt of a Registration
                Notice, BP may by written notice to Company elect to include in
                the Public Offering all of the Common Stock and Preferred Stock
                owned by BP to the extent any Common Stock or Preferred Stock
                is covered in the Public Offering proposed by the Company. If
                BP elects to include any of the Common Stock or Preferred Stock
                owned by it in such Public Offering, it must elect to include
                all of such Common Stock or Preferred Stock, as applicable.

           9.   Section 5(g) of the Agreement is amended to read, in its
entirety, as follows:

                If BP sells less than all of the Common Stock owned by it in a
                Public Offering, then the Target Value shall be reduced by
                multiplying it by a fraction, the numerator of which is the
                number of shares of the Common Stock owned by BP and sold in
                such Public Offering and the denominator of which is the number
                of shares of the Common Stock owned by BP as of the date of
                this Agreement, plus the number of shares of Common Stock
                received by BP after the date of this Agreement in connection
                with the conversion of shares of Preferred Stock (all of such
                shares included in such denominator to be adjusted for any
                stock splits, reverse stock splits, stock dividends or similar
                events occurring after they are issued to BP).

           10.  Section 6 of the Agreement is amended to read, in its entirety,
as follows:

                The Company will not authorize or issue Common Stock, Preferred
                Stock or Other Equity, unless the price for, and terms of, such
                Common Stock, Preferred Stock or Other Equity are reasonable
                and established on a good faith basis.

           11.  Clause (ii) of the first sentence of Section 7(b) of the
Agreement is amended to read, in its entirety, as follows:

                substantially all such cash, cash equivalents or
                publicly-traded securities, or the cash received from the sale
                or collection thereof, net


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                of expenses and debt repayment, is to the extent feasible and
                as soon as practicable distributed ratably to the holders of
                Common Stock (subject to the rights of the holders of Preferred
                Stock).

           12.  Clause (ii) of the first sentence of Section 8(a) of the
Agreement is amended to read, in its entirety, as follows:

                Common Stock, Preferred Stock or Other Equity or debt sold to
                Buyer or its Affiliates for cash consideration at fair market
                value determined reasonably and good faith and subject, where
                applicable, to BP's preemption rights under Section 3 above;

           13.  Clause (vi) is added at the end of the first sentence of Section
8(a) of the Agreement as follows:

                or (vi) the original issuance of not more than 1,500 shares of
                Preferred Stock to Buyer prior to November 10, 1997

           14.  The last sentence of Section 8(a) is amended to read, in its
entirety, as follows:

                For the avoidance of doubt, dividends declared and paid ratably
                from time to time to all holders of Common Stock, cash
                dividends declared and paid ratably from time to time to all
                holders of Preferred Stock, the redemption of all Preferred
                Stock and the conversion of any outstanding shares of Preferred
                Stock into shares of Common Stock are not considered to be
                Related Party Transactions.

           15.  Section 9 of the Agreement is amended to read, in its entirety,
as follows:

                The Company shall not, without the prior written consent of BP,
                redeem any Common Stock, Preferred Stock or Other Equity unless
                such redemption:

                        (i)   applies only to Common Stock, and ratably to the
                        shares of Common Stock owned by BP as a percentage of
                        all outstanding shares of Common Stock; or

                        (ii)   is of Common Stock, Preferred Stock or Other
                        Equity held directly or indirectly by individuals
                        within the management group; or



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                        (iii)  applies only to all outstanding shares of
                        Preferred Stock.

           16.  Section 10 of the Agreement is amended to read, in its entirety,
as follows:

                After June 30, 1997, each certificate evidencing Common Stock
                or Preferred Stock, and each certificate issued in exchange for
                or upon the transfer of any Common Stock or Preferred Stock,
                shall be stamped or otherwise imprinted with a legend in
                substantially the following form:

                        The securities represented by this certificate are
                        subject to a Stockholders Agreement dated as of October
                        30, 1996, as amended, among the issuer of such
                        securities (the "Company") and all of the Company's
                        stockholders. A copy of such Stockholders Agreement
                        will be furnished without charge by the Company to the
                        holder hereof upon written request.

           17.  Section 12 of the Agreement is amended to read, in its entirety,
as follows:

                Prior to transferring any Common Stock or Preferred Stock
                (other than, in either case, in a Public Offering) to any
                Person, the transferring Stockholder shall cause the
                prospective transferee to execute and deliver to the Company
                and the other Stockholders a counterpart of this Agreement.

           18.  Paragraph (a) of Section 14 of the Agreement is amended to read,
in its entirety, as follows:

                In the event of a proposed Transfer of Common Stock or
                Preferred Stock (other than to Buyer or an Affiliate of Buyer)
                by Buyer or any Affiliate of Buyer (the "Transferring
                Stockholder"), the Transferring Stockholder shall deliver a
                written notice (the "Sale Notice") to BP, specifying in
                reasonable detail the identity of the proposed transferee(s)
                and the terms and conditions of such Transfer. BP may elect to
                participate in the contemplated Transfer by delivering written
                notice to the Transferring Stockholder within 15 days after
                receipt by BP of the Sale Notice. If BP elects to participate
                in such Transfer, BP will be entitled to sell in the
                contemplated Transfer, at the same price and on the same terms
                as the Transferring Stockholder, a percentage of the Common
                Stock and Preferred Stock, as applicable, to be sold,


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                assigned or otherwise transferred in the contemplated Transfer
                equal to the percentage of Common Stock and Preferred Stock, as
                applicable, then outstanding that are BP Shares. Buyer shall
                use its best efforts to obtain the agreement of the prospective
                transferee(s) to the participation in any contemplated
                Transfer, to the extent BP elects to participate in the manner
                set forth above, and Buyer and its Affiliates shall not
                Transfer any shares of Common Stock or Preferred Stock to the
                prospective transferee(s) if the prospective transferee(s)
                declines to allow such participation of BP.

           19.  The reference to "Common Stock" in the first sentence of Section
14(b)(i) of the Agreement is changed to "Common Stock or Preferred Stock".

           20.  The last sentence of Section 14(b)(i) of the Agreement is
amended to read, in its entirety, as follows:

                BP Shares shall be included in such sale in an amount equal to
                the product of (1) the number of shares of Common Stock or
                Preferred stock, as applicable, held by BP times (2) the ratio
                of the shares of Common Stock or Preferred Stock, as
                applicable, proposed to be sold by Buyer and its Affiliates to
                the total shares of Common Stock or Preferred Stock, as
                applicable, owned by Buyer and its Affiliates.

           21.  The reference to "Common Stock" in Section 14(b)(ii) is changed
to "Common Stock or Preferred Stock, as applicable,".

           22.  The first sentence of Section 15 of the Agreement is amended to
read, in its entirety, as follows:

                Any actual or attempted sale, transfer, assignment, pledge or
                other encumbrance or disposition of any shares of Common Stock
                or Preferred Stock in violation of any provision of this
                Agreement shall be void, and the Company shall not record such
                transfer on its books or treat any purported transferee of such
                shares as the owner of such shares for any purpose.

           23.  The first sentence of Section 20 of the Agreement is amended to
read, in its entirety, as follows:

                Except as otherwise provided herein, this Agreement shall bind
                and inure to the benefit of, and be enforceable by, (a) the
                Company and its


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                successors and assignees and (b) the Stockholders and any
                subsequent holders of Common Stock or Preferred Stock and the
                respective successors and assigns of each of them, so long as
                they hold Common Stock or Preferred Stock, as applicable.

           24.  Except as specifically set forth in this Amendment, the
Agreement shall remain in full force and effect.

           IN WITNESS WHEREOF, intending to be legally bound, the Company, BP
and the Buyer has executed this Amendment on the day and year first above
written.


                                               UNIFRAX CORPORATION


                                               By /s/William P. Kelly
                                                  -------------------------
                                                  Name: William P. Kelly
                                                  Title:   President


                                               BP EXPLORATION (ALASKA) INC.


                                               By /s/P. D. Wilbur
                                                  -------------------------
                                                  Name: Peter D. Wilbur
                                                  Title:   Secretary


                                               UNIFRAX HOLDING CO.


                                               By /s/John Nestor
                                                  -------------------------
                                                  Name: John G. Nestor
                                                  Title:   President