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                                                                     EXHIBIT 4.8



                            OBLIGOR PLEDGE AGREEMENT


         THIS OBLIGOR PLEDGE AGREEMENT (as amended, supplemented, amended and
restated or otherwise modified from time to time, this "Pledge Agreement"),
dated as of July 23, 1999, among Sterling Chemicals, Inc., a Delaware
corporation (the "Company"), and each of the Persons (such capitalized term and
all other capitalized terms not otherwise defined herein shall have the meanings
provided for or incorporated by reference in Article I below) identified on the
signature pages hereto and each other Person that may from time to time become a
party to this Pledge Agreement (each a "Pledgor" and collectively the
"Pledgors"), and The CIT Group/Business Credit, Inc., as Administrative Agent
for each of the Fixed Assets Secured Parties.


                              W I T N E S S E T H:

         WHEREAS, pursuant to a Revolving Credit Agreement, dated as of the date
hereof (together with all amendments, supplements, restatements and other
modifications, if any, from time to time thereafter made thereto, the "Credit
Agreement"), among the Company, Sterling Canada, Inc., a Delaware corporation,
Sterling Pulp Chemicals US, Inc., a Delaware corporation, Sterling Pulp
Chemicals, Inc., a Georgia corporation, Sterling Fibers, Inc., a Delaware
corporation, Sterling Chemicals Energy, Inc., a Delaware corporation, and
Sterling Chemicals International, Inc., a Delaware corporation, (collectively,
the "Borrowers"), the various financial institutions as are, or may from time to
time become, parties thereto (the "Lenders"), DLJ Capital Funding, Inc., as the
Syndication Agent, Credit Suisse First Boston, as the Documentation Agent, and
the Administrative Agent, the Lenders and the Issuer have extended Commitments
to make Credit Extensions to the Borrowers;

         WHEREAS, as a condition precedent to the making of any Credit Extension
under the Credit Agreement, the Pledgors are required to execute and deliver
this Pledge Agreement;

         WHEREAS, each Pledgor has duly authorized the execution, delivery and
performance of this Pledge Agreement; and

         WHEREAS, it is in the best interests of the Pledgors to execute this
Pledge Agreement inasmuch as the Pledgors will derive substantial direct and
indirect benefits from the Credit Extensions made from time to time to the
Borrowers by the Lenders pursuant to the Credit Agreement;

         NOW THEREFORE, for good and valuable consideration the receipt of which
is hereby acknowledged, and in order to induce the Fixed Assets Lenders to make
Fixed Assets Loans (including the initial Fixed Assets Loans) to the Borrowers
pursuant to the Credit

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Agreement, each of the Pledgors and the Administrative Agent, for the ratable
benefit of each Fixed Assets Secured Party, agrees as follows:



                                    ARTICLE I
                                   DEFINITIONS

         SECTION I.1. Certain Terms. The following terms (whether or not
underscored) when used in this Pledge Agreement, including its preamble and
recitals, shall have the following meanings (such definitions to be equally
applicable to the singular and plural forms thereof):

         "Administrative Agent" is defined in the preamble.

         "Borrowers" is defined in the first recital.

         "Collateral" is defined in Section 2.1.

         "Company" is defined in the preamble.

         "Credit Agreement" is defined in the first recital.

         "Distributions" means all stock dividends, liquidating dividends,
Capital Securities resulting from (or in connection with the exercise of) stock
splits, reclassifications, warrants, options, non-cash dividends, mergers or
consolidations, and all other distributions (whether similar or dissimilar to
the foregoing) on or with respect to any Pledged Shares or other Capital
Securities constituting Collateral, but shall not include Dividends.

         "Dividends" means cash dividends and cash distributions with respect to
any Pledged Shares or other Pledged Property made in the ordinary course of
business, but shall not include liquidating dividends.

         "Fixed Assets Termination Date" means the date on which all Fixed
Assets Obligations have been paid in full in cash, all Rate Protection
Agreements where the counterparty is a Fixed Assets Lender (or its Affiliate)
have been terminated and the Fixed Assets Loan Commitment shall have terminated.

         "Lenders" is defined in the first recital.

         "Pledge Agreement" is defined in the preamble.

         "Pledged Property" means all Pledged Shares, all other pledged Capital
Securities, all other equity securities, all assignments of any amounts due or
to become due with respect thereto and all other instruments which are now being
delivered by the Pledgor to the Administrative Agent or may from time to time
hereafter be delivered by the Pledgor to the Administrative Agent for the
purpose of pledge under this Pledge Agreement or any other Loan Document, and
all proceeds of any of the foregoing.


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         "Pledged Share Issuer" means each Person identified in Attachment 1
hereto as the issuer of the Pledged Shares identified opposite the name of such
Person and each other Person whose Capital Securities are required to be pledged
hereunder and under the Credit Agreement from time to time.

         "Pledged Shares" means the Capital Securities of any Pledged Share
Issuer in the amounts and percentages listed in Attachment 1 hereto.

         "Pledgor" and "Pledgors" are defined in the preamble.

         "Securities Act" is defined in clause (a) of Section 6.2.

         SECTION I.2. Credit Agreement Definitions. Unless otherwise defined
herein or the context otherwise requires, terms used in this Pledge Agreement,
including its preamble and recitals, have the meanings provided in the Credit
Agreement.

         SECTION I.3. U.C.C. Definitions. Unless otherwise defined herein or in
the Credit Agreement or the context otherwise requires, terms for which meanings
are provided in the U.C.C. are used in this Pledge Agreement, including its
preamble and recitals, with such meanings.


                                   ARTICLE II
                                     PLEDGE

         SECTION II.1. Grant of Security Interest. Each Pledgor hereby pledges,
hypothecates, assigns, charges, delivers and transfers to the Administrative
Agent, for the ratable benefit of each of the Fixed Assets Secured Parties, and
hereby grants to the Administrative Agent, for the ratable benefit of the Fixed
Assets Secured Parties, a continuing security interest in, all of the following
property (collectively, the "Collateral"):

                  (a) all issued and outstanding Pledged Shares of each Pledged
         Share Issuer identified in Item A of Attachment 1 hereto;


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                  (b) all other Pledged Shares issued from time to time;

                  (c) all other Pledged Property, whether now or hereafter
         delivered to the Administrative Agent in connection with this Pledge
         Agreement;

                  (d) all Dividends, Distributions and other payments and rights
         with respect to any Pledged Property; and

                  (e) all proceeds of any of the foregoing.

         SECTION II.2. Security for Fixed Assets Obligations. This Pledge
Agreement secures the payment in full and in cash of all Fixed Assets
Obligations.

         SECTION II.3. Delivery of Pledged Property. All certificates or
instruments representing or evidencing any Collateral, including all Pledged
Shares shall be delivered to and held by or on behalf of the Administrative
Agent pursuant hereto, shall be in suitable form for transfer by delivery and
shall be accompanied by all necessary instruments of transfer or assignment,
duly executed in blank.

         SECTION II.4. Dividends on Pledged Shares. In the event that any
Dividend is to be paid on any Pledged Share at a time when (x) no Default of the
nature referred to in Section 8.1.9 of the Credit Agreement has occurred and is
continuing, and (y) no Event of Default has occurred and is continuing, such
Dividend may be paid directly to the applicable Pledgor. If any such Default or
Event of Default has occurred and is continuing, then any such Dividend shall be
paid directly to the Administrative Agent.

         SECTION II.5. Continuing Security Interest. This Pledge Agreement shall
create a continuing security interest in the Collateral and shall:

                  (a) remain in full force and effect until the Fixed Assets
         Termination Date;

                  (b) be binding upon each Pledgor and its successors,
         transferees and assigns; and

                  (c) inure, together with the rights and remedies of the
         Administrative Agent hereunder, to the benefit of the Fixed Assets
         Secured Parties.

Without limiting the foregoing clause (c), any Fixed Assets Lender may assign or
otherwise transfer (in whole or in part) any Fixed Assets Loan Commitment or any
Fixed Assets Loan held by it to any other Person or entity, and such other
Person or entity shall thereupon become vested with all the rights and benefits
in respect thereof granted to such Fixed Assets Lender under any Loan Document
(including this Pledge Agreement) or otherwise, subject, however, to any
contrary provisions in such assignment or transfer, and to the provisions of

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Section 10.11 of the Credit Agreement. The security interest granted herein
shall terminate and all rights to the Collateral shall revert to each Pledgor on
the Fixed Assets Termination Date. Upon any such termination or release of
Collateral, the Administrative Agent will, at each Pledgor's sole expense,
deliver to such Pledgor, without any representations, warranties or recourse of
any kind whatsoever, all certificates and instruments representing or evidencing
all Pledged Shares, together with all other Collateral held by the
Administrative Agent hereunder, and execute and deliver to such Pledgor such
documents as such Pledgor shall reasonably request to evidence such termination
or release.

         SECTION II.6. Security Interest Absolute. All rights of the
Administrative Agent and the Liens granted to the Administrative Agent
hereunder, and all obligations of each Pledgor hereunder, shall be absolute and
unconditional, irrespective of

                  (a) any lack of validity or enforceability of any Loan
         Document,

                  (b) the failure of any Fixed Assets Secured Party

                           (i) to assert any claim or demand or to enforce any
                  right or remedy against any Pledgor, any other Obligor or any
                  other Person under the provisions of the Loan Documents or
                  otherwise, or

                           (ii) to exercise any right or remedy against any
                  guarantor of, or collateral securing, any Fixed Assets
                  Obligations of any Pledgor or any other Obligor,

                  (c) any change in the time, manner or place of payment of, or
         in any other term of, all or any of the Fixed Assets Obligations or any
         other extension, compromise or renewal of any Obligation of any Pledgor
         or any other Obligor,

                  (d) any reduction, limitation, impairment or termination of
         any Fixed Assets Obligation of any Pledgor or any other Obligor for any
         reason (other than the repayment in full and in cash of all Fixed
         Assets Obligations), including any claim of waiver, release, surrender,
         alteration or compromise, and shall not be subject to (and each Pledgor
         hereby waives any right to or claim of) any defense or set-off,
         counterclaim, recoupment or termination whatsoever by reason of the
         invalidity, illegality, nongenuineness, irregularity, compromise or
         unenforceability of, or any other event or occurrence affecting, any
         Fixed Assets Obligation of any Pledgor, any other Obligor or otherwise,

                  (e) any amendment to, rescission, waiver, or other
         modification of, or any consent to departure from, any of the terms of
         the Loan Documents,

                  (f) any addition, exchange, release, surrender or
         non-perfection of any collateral (including the Collateral), or any
         amendment to or waiver or release of or

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         addition to or consent to departure from any guaranty, for any of the
         Fixed Assets Obligations, or

                  (g) any other circumstances which might otherwise constitute a
         defense available to, or a legal or equitable discharge of, any
         Pledgor, any other Obligor, any surety or any guarantor.

         SECTION II.7. Postponement of Subrogation, etc. No Pledgor will
exercise any rights which it may acquire by reason of any payment made
hereunder, whether by way of subrogation, reimbursement or otherwise, until the
Fixed Assets Termination Date. Any amount paid to any Pledgor on account of any
payment made hereunder prior to the Fixed Assets Termination Date shall be held
in trust for the benefit of the Fixed Assets Secured Parties and shall
immediately be paid to the Administrative Agent, for the ratable benefit of the
Fixed Assets Secured Parties, and credited and applied against the Fixed Assets
Obligations, whether matured or unmatured, in accordance with the terms of the
Credit Agreement; provided, however, that if

                  (a) any Pledgor has made payment to the Administrative Agent
         for the ratable benefit of the Fixed Assets Secured Parties of all or
         any part of the Fixed Assets Obligations, and

                  (b) the Fixed Assets Termination Date has occurred,

each Fixed Assets Secured Party agrees that, at such Pledgor's request, the
Administrative Agent, on behalf of the Fixed Assets Secured Parties, will
execute and deliver to such Pledgor appropriate documents (without recourse and
without representation or warranty) necessary to evidence the transfer by
subrogation to such Pledgor of an interest in the Fixed Assets Obligations
resulting from such payment by such Pledgor. In furtherance of the foregoing,
prior to the Fixed Assets Termination Date, each Pledgor shall refrain from
taking any action or commencing any proceeding against any other Obligor (or its
successors or assigns, whether in connection with a bankruptcy proceeding or
otherwise) to recover any amounts in respect of payments made under this Pledge
Agreement to the Administrative Agent or any other Fixed Assets Secured Party.


                                   ARTICLE III
                         REPRESENTATIONS AND WARRANTIES

         SECTION III.1. Warranties, etc. Each Pledgor represents and warrants
unto each Fixed Assets Secured Party, as at the date of each pledge and delivery
hereunder (including each pledge and delivery of Pledged Shares) by such Pledgor
to the Administrative Agent of any Collateral, as set forth in this Article.


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         SECTION III.2. Ownership, No Liens, etc. Each Pledgor is the legal and
beneficial owner of, and has good and valid title to (and has full right and
authority to pledge and assign) the Collateral, free and clear of all Liens,
except any Lien granted pursuant hereto in favor of the Administrative Agent or
any Permitted Lien.

         SECTION III.3. Valid Security Interest. The execution and delivery of
this Pledge Agreement creates a valid first-priority security interest in the
Collateral and (a) in the case of the Pledged Shares, upon the delivery of such
Collateral to the Administrative Agent, such security interest will be a valid
first-priority, perfected security interest; and (b) in the case of all other
Collateral, upon the filing of the U.C.C. financing statements (Form U.C.C.-1)
delivered by the Pledgors to the Administrative Agent with respect to such
Collateral, such security interest will be a valid first-priority, perfected
security interest. Each Pledgor has filed all U.C.C. financing statements (Form
U.C.C.-1) referred to above in the appropriate offices therefor (or has provided
the Administrative Agent with copies thereof suitable for filing in such
offices) and has taken all of the other actions referred to above necessary to
create perfected and first-priority security interests in the applicable
Collateral.

         SECTION III.4. As to Pledged Shares. In the case of any Pledged Shares
constituting Collateral, all such Pledged Shares are duly authorized and validly
issued, fully paid and non-assessable, and constitute all of the issued and
outstanding Capital Securities of each Pledged Share Issuer. No Pledgor has any
Subsidiaries of which it directly owns any Capital Securities other than the
Pledged Share Issuers, Foreign Restricted Subsidiaries or Unrestricted
Subsidiaries. All Pledged Shares are certificated, have been delivered to the
Administrative Agent with stock powers, accompanied by undated instruments of
transfer duly executed in blank and the Administrative Agent has "control" (as
defined in the U.C.C.) of such Pledged Shares.

         SECTION III.5. Authorization, Approval, etc. No authorization, approval
or other action by, and no notice to or filing with, any Governmental Authority,
regulatory body or other Person (other than those that have been, or on the
Effective Date will be, duly obtained or made and which are, or on the Effective
Date will be, in full force and effect) is required either

                  (a) for the pledge by such Pledgor of any Collateral pursuant
         to this Pledge Agreement or for the execution, delivery and performance
         of this Pledge Agreement by such Pledgor, or

                  (b) for the exercise by the Administrative Agent of the voting
         or other rights provided for in this Pledge Agreement, or, except with
         respect to any Pledged Shares as may be required in connection with a
         disposition of such Pledged Shares by laws affecting the offering and
         sale of securities generally, the remedies in respect of the Collateral
         pursuant to this Pledge Agreement,

provided, however, that in order to exercise the voting and certain other rights
provided for in this Pledge Agreement, the Pledged Shares must be transferred
into the name of the Administrative Agent on the books and records of the
Pledged Share Issuer prior to the exercise of such voting or other rights.


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         SECTION III.6. Compliance with Laws. Each Pledgor is in compliance with
the requirements of all applicable laws (including, the provisions of the Fair
Labor Standards Act), rules, regulations and orders of every Governmental
Authority, the non-compliance with which could have a Material Adverse Effect or
adversely affect the value of the Collateral.


                                   ARTICLE IV
                                    COVENANTS

         SECTION IV.1. Protect Collateral; Further Assurances, etc. Except for
the second priority Lien in favor of the Trustee on the Capital Securities of
each Borrower other than the Company and the second priority Lien in favor of
the trustee under the Senior Secured Discount Notes Indenture on the Capital
Securities of the Company, no Pledgor will sell, assign, transfer, pledge, or
encumber in any other manner the Collateral (except in favor of the
Administrative Agent hereunder or as permitted under Section 7.2.3 and 7.2.11 of
the Credit Agreement). Each Pledgor will warrant and defend the right and title
herein granted unto the Administrative Agent in and to the Collateral (and all
right, title and interest represented by the Collateral) against the claims and
demands of all Persons whomsoever. Each Pledgor agrees that at any time, and
from time to time, at the expense of such Pledgor, such Pledgor will promptly
execute and deliver all further instruments, and take all further action, that
may be necessary or desirable, or that the Administrative Agent may reasonably
request, in order to perfect and protect any security interest granted or
purported to be granted hereby or to enable the Administrative Agent to exercise
and enforce its rights and remedies hereunder with respect to any Collateral. No
Pledgor will permit any Pledged Share Issuer to issue any Capital Securities
unless the same are immediately delivered and pledged to the Administrative
Agent hereunder.

         SECTION IV.2. Stock Powers, etc. Each Pledgor agrees that all Pledged
Shares (and all other Capital Securities constituting Collateral) delivered by
such Pledgor pursuant to this Pledge Agreement will be accompanied by duly
executed, undated stock powers or other equivalent instruments of transfer
reasonably acceptable to the Administrative Agent. Each Pledgor will, from time
to time upon the reasonable request of the Administrative Agent, promptly
deliver to the Administrative Agent such stock powers, instruments and similar
documents, reasonably satisfactory in form and substance to the Administrative
Agent, with respect to the Collateral as the Administrative Agent may reasonably
request and will, from time to time upon the request of the Administrative Agent
after the occurrence of any Event of Default, promptly cause each Pledged Share
Issuer to transfer any Pledged Shares or other Capital Securities constituting
Collateral into the name of any nominee designated by the Administrative Agent.

         SECTION IV.3. Continuous Pledge. Subject to Section 2.4, each Pledgor
will, at all times, keep pledged to the Administrative Agent pursuant hereto all
Pledged Shares and all other Capital Securities constituting Collateral, all
Dividends and Distributions with respect thereto, and all other Collateral and
other Capital Securities, instruments, proceeds and rights from time

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to time received by or distributable to such Pledgor in respect of any
Collateral. Any Distributions on Pledged Shares consisting of Capital Securities
will be certificated.

         SECTION IV.4. Voting Rights; Dividends, etc. Each Pledgor agrees:

                  (a) if any Default of the nature referred to in Section 8.1.9
         of the Credit Agreement or an Event of Default shall have occurred and
         be continuing, promptly upon receipt thereof by such Pledgor and
         without any request therefore by the Administrative Agent, to deliver
         (properly endorsed where required hereby or requested by the
         Administrative Agent) to the Administrative Agent all Dividends,
         Distributions and all proceeds of the Collateral, all of which shall be
         held by the Administrative Agent as additional Collateral for use in
         accordance with Section 6.4; and

                  (b) if any Event of Default shall have occurred and be
         continuing and the Administrative Agent shall have notified such
         Pledgor of the Administrative Agent's intention to exercise its voting
         power under this Section:

                           (i) the Administrative Agent may exercise (to the
                  exclusion of such Pledgor) the voting power and all other
                  incidental rights of ownership with respect to any Pledged
                  Shares or other Capital Securities constituting Collateral and
                  such Pledgor hereby grants the Administrative Agent an
                  irrevocable proxy, exercisable under such circumstances, to
                  vote the Pledged Shares and such other Collateral; and

                           (ii) promptly to deliver to the Administrative Agent
                  such additional proxies and other documents as may be
                  necessary to allow the Administrative Agent to exercise such
                  voting power.

All Dividends, Distributions and proceeds which may at any time and from time to
time be held by any Pledgor but which such Pledgor is then obligated to deliver
to the Administrative Agent, shall, until delivery to the Administrative Agent,
be held by such Pledgor separate and apart from its other property in trust for
the Administrative Agent. The Administrative Agent agrees that unless an Event
of Default shall have occurred and be continuing and the Administrative Agent
shall have given the notice referred to in this Section, each Pledgor have the
exclusive power to exercise all voting and other consensual rights with respect
to any Capital Securities(including any of the Pledged Shares) constituting
Collateral and the Administrative Agent shall, upon the written request of such
Pledgor, promptly deliver such proxies and other documents, if any, as shall be
reasonably requested by such Pledgor which are necessary to allow such Pledgor
to exercise such powers with respect to any such share of Capital Securities
(including any of the Pledged Shares) constituting Collateral; provided,
however, that no vote shall be cast, or consent, waiver or ratification given,
or action taken by any Pledgor that would materially impair the value of any
Collateral or be inconsistent with or violate any provision of the Loan
Documents.


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                                    ARTICLE V
                            THE ADMINISTRATIVE AGENT

         SECTION V.1. Administrative Agent Appointed Attorney-in-Fact. Each
Pledgor hereby irrevocably appoints the Administrative Agent as such Pledgor's
attorney-in-fact, with full authority and in the name, place and stead of the
Pledgor or in its own name, from time to time in the Administrative Agent's
discretion, to take, upon the occurrence and during the continuance of any Event
of Default, any action and to execute any instrument which the Administrative
Agent may deem necessary or advisable to accomplish the purposes of this Pledge
Agreement, including without limitation:

                  (a) to ask, demand, collect, sue for, recover, compromise and
         receive and give acquittance and receipts for moneys due and to become
         due under or in respect of any of the Collateral;

                  (b) to receive, endorse and collect any drafts or other
         instruments, documents and chattel paper, in connection with clause (a)
         above; and

                  (c) to file any claims or take any action or institute any
         proceedings which the Administrative Agent may deem necessary or
         desirable for the collection of any of the Collateral or otherwise to
         enforce the rights of the Administrative Agent with respect to any of
         the Collateral.

Each Pledgor hereby acknowledges, consents and agrees that the power of attorney
granted pursuant to this Section is irrevocable and coupled with an interest.

         SECTION V.2. Administrative Agent May Perform. If any Pledgor fails to
perform any agreement contained herein, the Administrative Agent may itself
perform, or cause performance of, such agreement, and the expenses of the
Administrative Agent incurred in connection therewith shall be payable by such
Pledgor pursuant to Section 6.5.

         SECTION V.3. Administrative Agent Has No Duty. The powers conferred on
the Administrative Agent hereunder are solely to protect its interest (on behalf
of the Fixed Assets Secured Parties) in the Collateral and shall not impose any
duty on it to exercise any such powers. Except for reasonable care of any
Collateral in its possession and the accounting for moneys actually received by
it hereunder, the Administrative Agent shall have no duty as to any Collateral
or responsibility for

                  (a) ascertaining or taking action with respect to calls,
         conversions, exchanges, maturities, tenders or other matters relative
         to any Pledged Property, whether or not the Administrative Agent has or
         is deemed to have knowledge of such matters, or

                  (b) taking any necessary steps to preserve rights against
         prior parties or any other rights pertaining to any Collateral.


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         SECTION V.4. Reasonable Care. The Administrative Agent is required to
exercise reasonable care in the custody and preservation of any of the
Collateral in its possession; provided, however, the Administrative Agent shall
be deemed to have exercised reasonable care in the custody and preservation of
any of the Collateral, if it takes such action for that purpose as the relevant
Pledgor reasonably requests in writing from time to time, but failure of the
Administrative Agent to comply with any such request at any time shall not in
itself be deemed a failure to exercise reasonable care. If an Event of Default
has occurred and is continuing, the Administrative Agent shall not be required
to comply with any request of the Pledgor with respect to the matters described
in this Section.


                                   ARTICLE VI
                                    REMEDIES

         SECTION VI.1. Certain Remedies. If any Event of Default shall have
occurred and be continuing:

                  (a) The Administrative Agent may exercise in respect of the
         Collateral, in addition to other rights and remedies provided for
         herein or otherwise available to it, all the rights and remedies of a
         secured party on default under the U.C.C. (whether or not the U.C.C.
         applies to the affected Collateral) and also may, without notice except
         as specified below, sell the Collateral or any part thereof in one or
         more parcels at public or private sale, at any of the Administrative
         Agent's offices or elsewhere, for cash, on credit or for future
         delivery, and upon such other terms as the Administrative Agent may
         deem commercially reasonable. Each Pledgor agrees that, to the extent
         notice of sale shall be required by law, at least ten days' prior
         notice to such Pledgor of the time and place of any public sale or the
         time after which any private sale is to be made shall constitute
         reasonable notification. The Administrative Agent shall not be
         obligated to make any sale of Collateral regardless of notice of sale
         having been given. The Administrative Agent may adjourn any public or
         private sale from time to time by announcement at the time and place
         fixed therefore, and such sale may, without further notice, be made at
         the time and place to which it was so adjourned.

                  (b) The Administrative Agent may

                           (i) transfer all or any part of the Collateral into
                  the name of the Administrative Agent or its nominee, with or
                  without disclosing that such Collateral is subject to the Lien
                  and security interest hereunder,

                           (ii) notify the parties obligated on any of the
                  Collateral to make payment to the Administrative Agent of any
                  amount due or to become due thereunder,

                           (iii) enforce collection of any of the Collateral by
                  suit or otherwise, and surrender, release or exchange all or
                  any part thereof, or compromise or extend or


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                  renew for any period (whether or not longer than the original
                  period) any obligations of any nature of any party with
                  respect thereto,

                           (iv) endorse any checks, drafts or other writings in
                  each Pledgor's name to allow collection of the Collateral,

                           (v) take control of any proceeds of the Collateral
                  and

                           (vi) execute (in the name, place and stead of any
                  Pledgor) endorsements, assignments, stock powers and other
                  instruments of conveyance or transfer with respect to all or
                  any of the Collateral.

         SECTION VI.2. Securities Laws. If the Administrative Agent shall
determine to exercise its right to sell all or any of the Collateral pursuant to
Section 6.1, each Pledgor agrees that, upon request of the Administrative Agent,
such Pledgor will use commercially reasonable efforts to, at its own expense:

                  (a) execute and deliver, and cause each issuer of the
         Collateral contemplated to be sold and the directors and officers
         thereof to execute and deliver, all such instruments and documents, and
         do or cause to be done all such other acts and things, as may be
         necessary or, in the opinion of the Administrative Agent, advisable to
         register such Collateral under the provisions of the Securities Act of
         1933, as from time to time amended (the "Securities Act"), and to cause
         the registration statement relating thereto to become effective and to
         remain effective for such period as prospectuses are required by law to
         be furnished, and to make all amendments and supplements thereto and to
         the related prospectus which, in the opinion of the Administrative
         Agent, are necessary or advisable, all in conformity with the
         requirements of the Securities Act and the rules and regulations of the
         Securities and Exchange Commission applicable thereto;

                  (b) use its best efforts to qualify the Collateral under the
         state securities or "Blue Sky" laws and to obtain all necessary
         governmental approvals for the sale of the Collateral, as requested by
         the Administrative Agent;

                  (c) cause each such issuer to make available to its security
         holders, as soon as practicable, an earnings statement that will
         satisfy the provisions of Section 11(a) of the Securities Act; and

                  (d) do or cause to be done all such other acts and things as
         may be necessary to make such sale of the Collateral or any part
         thereof valid and binding and in compliance with applicable law.

Each Pledgor further acknowledges the impossibility of ascertaining the amount
of damages that would be suffered by the Administrative Agent or the Fixed
Assets Secured Parties by reason of the failure by such Pledgor to perform any
of the covenants contained in this Section and,


<PAGE>   13

consequently, agrees that, if such Pledgor shall fail to perform any of such
covenants, it shall pay, as liquidated damages and not as a penalty, an amount
equal to the value (as determined by the Administrative Agent) of the Collateral
on the date the Administrative Agent shall demand compliance with this Section.

         SECTION VI.3. Compliance with Restrictions. Each Pledgor agrees that in
any sale of any of the Collateral whenever an Event of Default shall have
occurred and be continuing, the Administrative Agent is hereby authorized to
comply with any limitation or restriction in connection with such sale as it may
be advised by counsel is necessary in order to avoid any violation of applicable
law (including compliance with such procedures as may restrict the number of
prospective bidders and purchasers, require that such prospective bidders and
purchasers have certain qualifications and restrict such prospective bidders and
purchasers to persons who will represent and agree that they are purchasing for
their own account for investment and not with a view to the distribution or
resale of such Collateral), or in order to obtain any required approval of the
sale or of the purchaser by any Governmental Authority, and the Pledgor further
agrees that such compliance shall not result in such sale being considered or
deemed not to have been made in a commercially reasonable manner, nor shall the
Administrative Agent be liable nor accountable to any Pledgor for any discount
allowed by reason of the fact that such Collateral is sold in compliance with
any such limitation or restriction.

         SECTION VI.4. Application of Proceeds. All cash proceeds received by
the Administrative Agent in respect of any sale of, collection from or other
realization upon, all or any part of the Collateral may, in the discretion of
the Administrative Agent, be held by the Administrative Agent as additional
collateral security for, or then or at any time thereafter be applied (after
payment of any amounts payable to the Administrative Agent pursuant to Section
10.4 of the Credit Agreement and Section 6.5 below) in whole or in part by the
Administrative Agent against, all or any part of the Fixed Assets Obligations in
such order as the Administrative Agent shall elect. Any surplus of such cash or
other proceeds held by the Administrative Agent and remaining after the Fixed
Assets Termination Date, shall be paid over to the applicable Pledgor or to
whomsoever may be lawfully entitled to receive such surplus. The Pledgors shall
remain liable on a joint and several basis for any deficiency.

         SECTION VI.5. Indemnity and Expenses. Each Pledgor hereby jointly and
severally indemnifies and holds harmless the Administrative Agent from and
against any and all claims, losses and liabilities arising out of or resulting
from this Pledge Agreement (including enforcement of this Pledge Agreement),
except claims, losses or liabilities resulting from the Administrative Agent's
gross negligence or wilful misconduct, and each Pledgor will pay to the
Administrative Agent the amount of any and all reasonable expenses, including
the reasonable fees and disbursements of its counsel and of any experts and
agents, which the Administrative Agent may incur, in each case, in connection
with:

                  (a) the administration of this Pledge Agreement;


                                      -13-

<PAGE>   14

                  (b) the custody, preservation, use or operation of, or the
         sale of, collection from or other realization upon, any of the
         Collateral;

                  (c) the exercise or enforcement of any of the rights of the
         Administrative Agent hereunder; or

                  (d) the failure by any Pledgor to perform or observe any of
         the provisions hereof.


                                   ARTICLE VII
                            MISCELLANEOUS PROVISIONS

         SECTION VII.1. Loan Document. This Pledge Agreement is a Loan Document
executed pursuant to the Credit Agreement and shall (unless otherwise expressly
indicated herein) be construed, administered and applied in accordance with the
terms and provisions thereof.

         SECTION VII.2. Amendments, etc. No amendment to or waiver of any
provision of this Pledge Agreement nor consent to any departure by any Pledgor
herefrom shall in any event be effective unless the same shall be in writing and
signed by the Administrative Agent (on behalf of the Lenders or the Required
Lenders, as the case may be) and each Pledgor, and then such waiver or consent
shall be effective only in the specific instance and for the specific purpose
for which it is given.

         SECTION VII.3. Protection of Collateral. The Administrative Agent may
from time to time, at its option, and at the expense of the Pledgors, perform
any act which any Pledgor agrees hereunder to perform and which such Pledgor
shall fail to perform after being requested in writing so to perform (it being
understood that no such request need be given after the occurrence and during
the continuance of an Event of Default) and the Administrative Agent may from
time to time take any other action which the Administrative Agent reasonably
deems necessary for the maintenance, preservation or protection of any of the
Collateral or of its security interest therein.

         SECTION VII.4. Addresses for Notices. All notices and other
communications provided for hereunder shall be in writing and addressed,
delivered or transmitted, if to any Pledgor, at the address or facsimile number
of the Company provided for in the Credit Agreement, and, if to the
Administrative Agent, at the address or facsimile number provided for in the
Credit Agreement, or as to any such party at such other address or facsimile
number as shall be designated by such party in a written notice to each other
party complying as to delivery with the terms of this Section. Any notice,
(a)(i) if mailed and properly addressed with postage prepaid or (ii) if properly
addressed and sent by pre-paid courier service, shall be deemed given when such
notice has been received or (b) if transmitted by facsimile, shall be deemed
given when transmitted (and telephonic confirmation of receipt thereof has been
received).


                                      -14-

<PAGE>   15

         SECTION VII.5. Headings. The various headings of this Pledge Agreement
are inserted for convenience only, and shall not affect the meaning or
interpretation of this Pledge Agreement or any provisions hereof.

         SECTION VII.6. Severability. Any provision of this Pledge Agreement
which is prohibited or unenforceable in any jurisdiction shall, as to such
provision and such jurisdiction, be ineffective to the extent of such
prohibition or unenforceability, without invalidating the remaining provisions
of this Pledge Agreement or affecting the validity or enforceability of such
provision in any other jurisdiction.

         SECTION VII.7. Governing Law. THIS PLEDGE AGREEMENT SHALL BE DEEMED TO
BE A CONTRACT MADE UNDER AND GOVERNED BY THE INTERNAL LAWS OF THE STATE OF NEW
YORK, EXCLUDING THE LAW OF CONFLICTS BUT GIVING EFFECT TO FEDERAL LAWS
APPLICABLE TO NATIONAL BANKS.

         SECTION VII.8. Counterparts. This Pledge Agreement may be executed by
the parties hereto in several counterparts, each of which shall be deemed to be
an original (whether such counterpart is originally executed or an electronic
copy of an original) and all of which shall constitute together but one and the
same agreement. This Pledge Agreement shall become effective and binding upon
any Pledgor when a counterpart hereof executed on behalf of such Pledgor shall
have been received by the Administrative Agent.

         SECTION VII.9. Additional Pledgors. Upon the execution and delivery by
any other Person of an instrument in the form of Annex I hereto, together with
the Schedule thereto, such Person shall become a "Pledgor" hereunder with the
same force and effect as if originally named as a Pledgor herein. The execution
and delivery of any such instrument shall not require the consent of any other
Pledgor hereunder. The rights and obligations of each Pledgor hereunder shall
remain in full force and effect notwithstanding the addition of any new Pledgor
as a party to this Pledge Agreement.


                                      -15-

<PAGE>   16



         IN WITNESS WHEREOF, the parties hereto have caused this Pledge
Agreement to be duly executed and delivered by their respective officers
thereunto duly authorized as of the day and year first above written.


                                     STERLING CHEMICALS, INC.




                                     By
                                       --------------------------------------
                                         Title:


                                     STERLING CANADA, INC.


                                     By
                                       --------------------------------------
                                         Title:


                                     STERLING PULP CHEMICALS US, INC.


                                     By
                                       --------------------------------------
                                         Title:


                                     THE CIT GROUP/BUSINESS CREDIT, INC.,
                                          as Administrative Agent


                                     By
                                       --------------------------------------
                                         Title:


                                      -16-

<PAGE>   17

                                  ATTACHMENT 1
                                       to
                                Pledge Agreement



[NAME OF PLEDGOR]


<TABLE>
<CAPTION>
Pledged Shares                          Capital Securities
--------------              --------------------------------------------
                            Authorized      Outstanding      % of Shares
Pledged Share Issuer          Shares           Shares          Pledged
--------------------        ----------      -----------      -----------
<S>                        <C>              <C>              <C>
</TABLE>



<PAGE>   18


                                                                         ANNEX I
                                                     to Obligor Pledge Agreement


                     SUPPLEMENT TO OBLIGOR PLEDGE AGREEMENT

         This SUPPLEMENT NO. ___, dated as of ________ __, ____ (this
"Supplement"), to the Obligor Pledge Agreement, dated as of July __, 1999 (as
amended, supplemented, amended and restated or otherwise modified from time to
time, the "Pledge Agreement"), among the initial signatories thereto and each
other Person which from time to time thereafter became a party thereto pursuant
to Section 7.9 thereof (each, individually, a "Pledgor", and, collectively, the
"Pledgors"), in favor of THE CIT GROUP/BUSINESS CREDIT INC., as Administrative
Agent for each of the Fixed Assets Secured Parties (such term and all other
capitalized terms being used herein with the meanings provided, or incorporated
by reference, in the Pledge Agreement), is made by the undersigned.


                              W I T N E S S E T H:

         WHEREAS, pursuant to a Revolving Credit Agreement, dated as of July __,
1999 (together with all amendments, supplements, restatements and other
modifications, if any, from time to time thereafter made thereto, the "Credit
Agreement"), among the Company, Sterling Canada, Inc., a Delaware corporation,
Sterling Pulp Chemicals US, Inc., a Delaware corporation, Sterling Pulp
Chemicals, Inc., a Georgia corporation, Sterling Fibers, Inc., a Delaware
corporation, Sterling Chemicals Energy, Inc., a Delaware corporation, and
Sterling Chemicals International, Inc., a Delaware corporation, (collectively,
the "Borrowers"), the various financial institutions as are, or may from time to
time become, parties thereto (the "Lenders"), DLJ Capital Funding, Inc., as the
Syndication Agent, Credit Suisse First Boston as the Documentation Agent and the
Administrative Agent, the Lenders and the Issuer have extended Commitments to
make Credit Extensions to the Borrowers;

         WHEREAS, as a condition precedent to the making and maintenance of
Fixed Assets Loans under the Credit Agreement, the undersigned is required to
execute and deliver this Supplement;

         WHEREAS, the undersigned has duly authorized the execution, delivery
and performance of this Supplement and the Pledge Agreement;

         WHEREAS, the Pledge Agreement provides that additional parties may
become Pledgors under the Pledge Agreement by execution and delivery of an
instrument in the form of this Supplement;


<PAGE>   19

         WHEREAS, pursuant to the provisions of Section 7.9 of the Pledge
Agreement, the undersigned is becoming a Pledgor under the Pledge Agreement; and

         WHEREAS, the undersigned desires to become a Pledgor under the Pledge
Agreement in order to induce the Fixed Assets Lenders to continue to make and
maintain Fixed Assets Loans under the Credit Agreement as consideration
therefor;

         NOW, THEREFORE, the undersigned agrees, for the benefit of each Fixed
Assets Secured Party, as follows:

         SECTION 1. In accordance with the Pledge Agreement, the undersigned by
its signature below becomes a Pledgor under the Pledge Agreement with the same
force and effect as if it were an original signatory thereto as a Pledgor and
Attachment I hereto shall be deemed to be part of Attachment I thereto. In
furtherance of the foregoing, each reference to a "Pledgor" in the Pledge
Agreement shall be deemed to include the undersigned.

         SECTION 2. The undersigned hereby represents and warrants that this
Supplement has been duly authorized, executed and delivered by the undersigned
and constitutes a legal, valid and binding obligation of the undersigned,
enforceable against it in accordance with its terms, except as such enforcement
may be limited by applicable bankruptcy, insolvency, reorganization, moratorium
or similar laws affecting creditors' rights generally and general equitable
principles.

         SECTION 3. Except as expressly supplemented hereby, the Pledge
Agreement shall remain in full force and effect in accordance with its terms.

         SECTION 4. In the event any one or more of the provisions contained in
this Supplement should be held invalid, illegal or unenforceable in any respect,
the validity, legality and enforceability of the remaining provisions contained
herein and in the Pledge Agreement shall not in any way be affected or impaired.

         SECTION 5. Without limiting the provisions of the Credit Agreement (or
any other Loan Document, including the Pledge Agreement), the undersigned agrees
to reimburse the Administrative Agent for its reasonable out-of-pocket expenses
in connection with this Supplement, including reasonable attorneys' fees and
expenses of the Administrative Agent.

         SECTION 6. THIS SUPPLEMENT SHALL BE DEEMED TO BE A CONTRACT MADE UNDER
AND GOVERNED BY THE INTERNAL LAWS OF THE


                                      -2-
<PAGE>   20

STATE OF NEW YORK, EXCLUDING THE LAW OF CONFLICTS BUT GIVING EFFECT TO FEDERAL
LAWS APPLICABLE TO NATIONAL BANKS.

         SECTION 7. This Supplement hereby incorporates by reference the
provisions of the Pledge Agreement, which provisions are deemed to be a part
hereof, and this Supplement shall be deemed to be a part of the Pledge
Agreement.

         SECTION 8. This Supplement may be executed by the parties hereto in
several counterparts, each of which shall be deemed to be an original (whether
such counterpart is originally executed or an electronic copy of an original)
and all of which shall constitute together but one and the same agreement. This
Supplement shall become effective and binding upon the Pledgor when a
counterpart hereof executed on behalf of the Pledgor shall have been received by
the Administrative Agent.

         IN WITNESS WHEREOF, the undersigned has caused this Supplement to be
duly executed and delivered by its officer thereunto duly authorized as of the
date first above written.

                                       [NAME OF ADDITIONAL PLEDGOR]


                                       By:
                                          ----------------------------------
                                             Name:
                                             Title:



ACKNOWLEDGED AND ACCEPTED BY:

THE CIT GROUP/BUSINESS CREDIT INC.,
 as Administrative Agent


By:
   ---------------------------------
      Name:
      Title:


                                      -3-

<PAGE>   21

                                                                 ATTACHMENT 1
                                                                      to
                                                               Supplement No. __
                                                               Pledge Agreement



[NAME OF PLEDGOR]


<TABLE>
<CAPTION>
 Pledged Shares
 --------------
Pledged Share Issuer                    Capital Securities
--------------------        --------------------------------------------
                            Authorized      Outstanding      % of Shares
                              Shares           Shares          Pledged
                            ----------      -----------      -----------
<S>                        <C>              <C>              <C>
</TABLE>



                                      -4-