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EXHIBIT C-1

FORM OF SUBSIDIARY PLEDGE AGREEMENT

ThisSUBSIDIARY PLEDGE AGREEMENT(as amended, modified or supplemented from time to time as provided herein, this "Agreement") is dated as of March 25, 2003, and made by each of UNION CARBIDE SUBSIDIARY C, INC., a Delaware corporation, UCMG LLC, a
Delaware limited liability company, and CATALYSTS, ADSORBENTS AND PROCESS SYSTEMS, INC., a Maryland corporation (collectively,"Grantors"and
each individually, a"Grantor"), in favor of THE DOW CHEMICAL COMPANY, a Delaware corporation ("TDCC"or "Lender").

W I T N E S S E T H:

WHEREAS, Union Carbide Corporation, a New York corporation ("Borrower") and Lender are parties to that certain
Revolving Credit Agreement dated as of the date hereof (as such agreement may be amended, modified or supplemented from time to time, the"Credit
Agreement");

WHEREAS,
pursuant to the terms of the Credit Agreement, Lender has agreed to make Loans and Credit Enhancements (as defined in the Credit Agreement) available to Borrower;

WHEREAS,
as a subsidiary of Borrower, each of the Guarantors will derive substantial direct and indirect benefits from such Loans and Credit Enhancements;

WHEREAS,
it is a condition precedent to the effectiveness of the Credit Agreement that each of the Guarantors shall have executed and delivered the Subsidiary Guarantee (as defined
below) to Lender;

WHEREAS,
it is a condition precedent to the effectiveness of the Credit Agreement that each of the Guarantors shall have executed and delivered this Subsidiary Pledge Agreement;

WHEREAS,
to secure the due and punctual payment and performance of, among other things, the Guaranteed Obligations (as defined below), each Grantor wishes to grant to TDCC a security
interest in the Collateral (as defined below) owned by such Grantor, subject to the limitations set forth herein;

NOW,
THEREFORE, in consideration of the premises and to induce TDCC to enter into the Credit Agreement and to induce TDCC to make and/or continue extensions of credit to Borrower
thereunder, each of the Grantors hereby agrees with TDCC as follows:

ARTICLE I

DEFINED TERMS

Section 1.1Definitions.

(a)   Unless
otherwise defined herein, terms defined in the Credit Agreement and used herein have the meanings given to them in the Credit Agreement.

(b)   Terms
used herein that are defined in the UCC have the meanings given to them in the UCC, including the following which are capitalized herein:



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(c)   The
following terms shall have the following meanings:

"Agreement"means this Subsidiary Pledge Agreement.

"Collateral"has the meaning specified inSection 2.1.

"Debt Obligations"means any Guaranteed Obligation that would constitute "Debt" as defined in Section 5.1 of the Participation
Agreement.

"Designated Joint Ventures"means any of the Pledged Collateral identified as a "Designated Joint Venture" on Schedule 2.

"LLC"means each limited liability company identified onSchedule 2.

"LLC Agreement"means each operating agreement with respect to an LLC, as each agreement has heretofore been and may hereafter be amended,
restated, supplemented or otherwise modified from time to time.

"Guaranteed Obligations"has the meaning specified in the Subsidiary Guarantee.

"Participation Agreement"means the Participation Agreement dated as of April 1, 2000, with respect to Union Carbide Trust
No. 2000-A, as amended from time to time.

"Partnership"means each partnership identified onSchedule 2.

"Partnership Agreement"means each partnership agreement governing a Partnership, as each such agreement has heretofore been and may
hereafter be amended, restated, supplemented or otherwise modified.

"Pledged Collateral"means, collectively, the Pledged Notes, the Pledged Stock, and the Pledged Partnership Interests, the Pledged LLC
Interests, all certificates or other instruments representing any of the foregoing, all Security Entitlements of Grantor in respect of any of the foregoing, all dividends, interest distributions,
cash, warrants, rights, instruments and other property or Proceeds from time to time received, receivable or otherwise distributed in respect of or in exchange for any or all of the foregoing.

"Pledged LLC Interests"means all of Grantor's right, title and interest as a member of the LLCs set forth on Schedule 2and all of Grantor's right, title and
interest in, to and under any LLC Agreement with respect thereto to which it is a party.

"Pledged Notes"means all right, title and interest of Grantor in the Instruments evidencing Intercompany Indebtedness (including any
Intercompany Notes) owed to Grantor, including all Indebtedness described onSchedule 2, issued by the obligors named therein, and all interest,
cash, Instruments and other property or Proceeds from time to time received, receivable or otherwise distributed in respect of or in exchange for any or all of such Indebtedness.

"Pledged Partnership Interests"means all of Grantor's right, title and interest as a limited and/or general partner in the Partnerships
set forth onSchedule 2and all of Grantor's right, title and interest in, to and under any Partnership Agreements with respect thereto to which
it is a party.

"Pledged Stock"means the shares of capital stock identified onSchedule 2; provided, however,that so long as doing
otherwise would result in adverse tax consequences to Grantor, the amount of outstanding capital stock of any
first tier Subsidiary that is not a Domestic Subsidiary that is pledged or deemed to be pledged hereunder shall not exceed the amount of shares of capital stock possessing up to but not exceeding 65%
of the voting power of all classes of capital stock of such Subsidiary entitled to vote.

"Securities Act"means the Securities Act of 1933, as amended.

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"UCC"means the Uniform Commercial Code as in effect in the State of New York on the date hereof;provided,
however,that in the event that, by reason of mandatory provisions of law, any or all of the attachment, perfection or priority of Lender's security interest in any Collateral
is governed by the Uniform Commercial Code as in effect in a jurisdiction other than the State of New York, the term "UCC" shall mean the Uniform Commercial Code as in effect on the date hereof in
such other jurisdiction for purposes of the provisions hereof relating to such attachment, perfection or priority and for purposes of definitions related to such provisions.

Section 1.2Certain Other Terms.

(a)   The
words"herein","hereof", "hereto"and"hereunder"and
similar words refer to this Agreement as a whole and not to any particular
Article, Section, subsection or clause in this Agreement.

(b)   References
herein to a Schedule, Article, Section, subsection or clause refer to the appropriate Schedule to, or Article, Section, subsection or clause in this
Agreement.

(c)   The
meanings given to terms defined herein shall be equally applicable to both the singular and plural forms of such terms.

(d)   Any
reference in this Agreement to a Loan Document shall include all appendices, exhibits and schedules thereto, and, unless specifically stated otherwise, all
amendments, restatements, supplements or other modifications thereto, and as the same may be in effect at any and all times such reference becomes operative.

(e)   The
term"including"means "including without limitation" except when used in the computation of time periods.

(f)    The
terms"Lender"and"Grantor"include their respective successors.

(g)   References
in this Agreement to any statute shall be to such statute as amended or modified and in effect from time to time.

ARTICLE II

GRANT OF SECURITY INTEREST

Section 2.1Collateral.For the purposes of this Agreement, all of the
following
property now owned by any Grantor or in which such Grantor now has any right, title or interests is collectively referred to as the"Collateral":

(a)   all
Pledged Collateral;

(b)   all
books and records pertaining to the property described in clause (a) of thisSection 2.1; and

(c)   to
the extent not otherwise included, all Proceeds and products of each of the foregoing and all accessions to, substitutions and replacements for, and any and all
proceeds of any insurance, indemnity, warranty or guaranty payable to such Grantor from time to time with respect to any of the foregoing.

Notwithstanding
anything to the contrary contained above, (1) so long as Borrower is bound by Section 5.5 of the Participation Agreement, the maximum principal amount of Debt Obligations
secured hereunder shall not exceed at any time outstanding the sum of (x) $800,000,000plus(y) the amount of Debt Obligations to the
extent secured by Designated Joint Ventures; and (2) any Pledged Collateral if the grant of a security interest therein would constitute a violation or breach of any other agreement to which
Grantor is bound. The parties hereto agree that the amount of Debt Obligations that may be secured under this Agreement is limited pursuant to the immediately
preceding sentence, as required under the Participation Agreement, to only a portion of the aggregate Debt Obligations owing or which may become owing to Lender and that any payments or repayments of
such Debt Obligations shall be and be deemed to be applied first to the portion of such Debt

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Obligations
that is not secured hereby, it being the parties' intent that the portion of such Debt Obligations last remaining unpaid shall be secured hereby.

Section 2.2Grant of Security Interest in Collateral.Subject to the
limitation
expressly set forth in Section 2.1, each Grantor, as security for the full, prompt and complete payment and performance when due (whether at stated maturity, by acceleration or otherwise) of
the Guaranteed Obligations, hereby collaterally pledges to Lender and grants to Lender a Lien on and security interest in, all of its right, title and interest in, to and under the Collateral.

ARTICLE III

REPRESENTATIONS AND WARRANTIES

To induce Lender to enter into the Credit Agreement, each Grantor hereby represents and warrants, as to itself and the Collateral it owns, to Lender that:

Section 3.1Title; No Other Liens.Except for the Lien granted to Lender
pursuant
to this Agreement and the other Liens permitted to exist on the Collateral under the Credit Agreement or the Subsidiary Guarantee, (a) Grantor is the record and beneficial owner of the Pledged
Collateral pledged by it hereunder constituting Instruments or certificated securities and owns each other item of Collateral in which a Lien is granted by it hereunder and (b) all such
Collateral is owned free and clear of any and all Liens.

Section 3.2Perfection and Priority.The security interest granted
pursuant to
this Agreement will constitute a valid and continuing perfected security interest in favor of Lender in the Collateral for which perfection is governed by the UCC upon (i) the completion of the
filings and other actions specified onSchedule 3(which, in the case of all filings and other documents referred to on such schedule, have been
delivered to Lender in completed and duly executed form), and (ii) the delivery to Lender of all Collateral consisting of Instruments and certificated securities, in each case properly endorsed
for transfer to Lender or in blank. Such security interest will be prior to all other Liens on the Collateral except for Customary Permitted Liens which have priority over Lender's Lien by operation
of law or otherwise as permitted under the Credit Agreement or the Subsidiary Guarantee.

Section 3.3State of Incorporation; Chief Executive Office.On the date
hereof
Grantor's jurisdiction of organization, organizational identification number, if any, and the location of Grantor's chief executive office or sole place of business is specified on Schedule 1.

Section 3.4Pledged Collateral.

(a)   The
Pledged Stock, Pledged Partnership Interests and Pledged LLC Interests pledged hereunder by Grantor constitutes that percentage of the issued and outstanding equity
of all classes of each issuer thereof as set forth onSchedule 2.

(b)   All
of the Pledged Stock, and (to the extent relevant) all Pledged Partnership Interests and Pledged LLC Interests have been duly and validly issued and are fully paid
and nonassessable.

(c)   All
Pledged Collateral consisting of certificated securities or Instruments has been delivered to Lender in accordance with Section 4.4(a).

ARTICLE IV

COVENANTS

As long as any of the Guaranteed Obligations (other than contingent indemnification Guaranteed Obligations not yet due and payable) remain outstanding, unless the
Lender otherwise consents in writing, each Grantor agrees with Lender that:

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Section 4.1Maintenance of Perfected Security Interest; Further Documentation.

(a)   Following
the perfection of any security interest created by this Agreement with respect to any item of Collateral, such Grantor will maintain such as a perfected
security interest having at least the priority described inSection 3.2and shall defend such security interest against the claims and demands of
all Persons.

(b)   Such
Grantor will furnish to Lender from time to time statements and schedules further identifying and describing the Collateral and such other reports in connection
with the Collateral as Lender may reasonably request, all in reasonable detail.

(c)   At
any time and from time to time, upon the written request of Lender, and at the sole expense of such Grantor, such Grantor will promptly and duly execute and deliver,
and have recorded, such further instruments and documents and take such further action as Lender may reasonably request for the purpose of obtaining or preserving the full benefits of this Agreement
and of the rights and powers herein granted, including the filing of any financing or continuation statement under the UCC (or other similar laws) in effect in any jurisdiction with respect to the
security interest created hereby.

Section 4.2Pledged Collateral.

(a)   Such
Grantor will deliver to Lender, all certificates or Instruments representing or evidencing any Pledged Collateral, in suitable form for transfer by delivery or, as
applicable, accompanied by such Grantor's endorsement, where necessary, or duly executed instruments of transfer or assignment in blank, all in form and substance reasonably satisfactory to Lender.
Lender shall have the right, upon the occurrence and during the continuance of an Event of Default, in its discretion and without notice to Grantor, to transfer to or to register in its name or in the
name of its nominees any or all of the Pledged Collateral. Lender shall have the right to, upon the occurrence and during the continuance of an Event of Default, exchange certificates or instruments
representing or evidencing any of the Pledged Collateral for certificates or instruments of smaller or larger denominations.

(b)   Except
as provided inArticle V, such Grantor shall be entitled to receive all cash dividends paid in respect of
the Pledged Collateral (other than liquidating dividends constituting a distribution of capital) with respect to the Pledged Collateral. Any sums paid upon or in respect of any of the Pledged
Collateral upon the liquidation or dissolution of any issuer of any of the Pledged Collateral, any distribution of capital made on or in respect of any of the Pledged Collateral or any property
distributed upon or with respect to any of the Pledged Collateral pursuant to the recapitalization or reclassification of the capital of any issuer of Pledged Collateral or pursuant to the
reorganization thereof shall, unless otherwise subject to a perfected security interest in favor of Lender, be delivered to Lender to be held by it hereunder as additional collateral security for the
Guaranteed Obligations or be deposited into an Approved Deposit Account. If any sums of money or property so paid or distributed in respect of any of the Pledged Collateral shall be received by such
Grantor, such Grantor shall, to the extent such money is not otherwise deposited into an Approved Deposit Account until such money or property is paid or delivered to Lender, hold such money or
property in trust for Lender, segregated from other funds of such Grantor, as additional security for the Guaranteed Obligations.

(c)   Except
as provided inArticle V, such Grantor will be entitled to exercise all voting, consent and corporate
rights with respect to the Pledged Collateral and to give consents, waivers or ratifications in respect thereof;provided, however,that no vote shall
be cast, consent given or right exercised or other action taken by Grantor which would have a Material Adverse Effect or which would be inconsistent with or breach the terms of the Credit Agreement,
this Agreement or any other Loan Document.

(d)   Such
Grantor will not agree to any amendment of an LLC Agreement or Partnership Agreement that in any way adversely affects the perfection of the security interest of
Lender in the Pledged Partnership Interests or Pledged LLC Interests pledged by Grantor hereunder, including electing to treat the membership interest or partnership interest of Grantor as a security
under Section 8-103 of the UCC.

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ARTICLE V

REMEDIAL PROVISIONS

Section 5.1Code and Other Remedies.During the continuance of an Event of
Default, Lender may exercise, in addition to all other rights and remedies granted to it in this Agreement and in any other instrument or agreement securing, evidencing or relating to the Guaranteed
Obligations, all rights and remedies of a secured party under the UCC or any other applicable law. Without limiting the generality of the foregoing, Lender, without demand of performance or other
demand, presentment, protest, advertisement or notice of any kind (in each case except any required by law referred to below) to or upon any Grantor or any other Person (all and each of which demands,
defenses, advertisements and notices are hereby waived), may in such circumstances forthwith collect, receive, appropriate and realize upon the Collateral, or any part thereof, and/or may forthwith
sell, lease, assign, give option or options to purchase, or otherwise dispose of and deliver the Collateral or any part thereof (or contract to do any of the foregoing), in one or more parcels at
public or private sale or sales, at any exchange, broker's board or office of Lender or elsewhere upon such terms and conditions as it may deem advisable and at such prices as it may deem best, for
cash or on credit or for future delivery without assumption of any credit risk. Lender shall have the right upon any such public sale or sales, and, to the extent permitted by law, to purchase the
whole or any part of the Collateral so sold, free of any right or equity of redemption in any Grantor, which right or equity is hereby waived and released. Lender shall apply the net proceeds of any
action taken by it pursuant to this Section 5.1, after deducting all reasonable costs and expenses of every kind incurred in connection therewith or incidental to the care or safekeeping of any
of the Collateral or in any way relating to the Collateral or the rights of Lender hereunder, including reasonable attorneys' fees and disbursements, to the payment in whole or in part of the
Guaranteed Obligations, in such order as the Credit Agreement or Subsidiary Guarantee shall proscribe, and only after such application and after the payment by Lender of any other amount required by
any provision of law, need Lender account for the surplus, if any, to the applicable Grantor. To the extent permitted by applicable law, each Grantor waives all claims, damages and demands it may
acquire against Lender arising out of the exercise by it of any rights hereunder. If any notice of a proposed sale or other disposition of Collateral shall be required by law, such notice shall be
deemed reasonable and proper if given at least 10 days before such sale or other disposition.

Section 5.2Pledged Collateral.

(a)   During
the continuance of an Event of Default, upon notice by Lender to Borrower or Grantors, (i) Lender shall have the right to receive any and all cash
dividends, payments or other Proceeds paid in respect of the Pledged Collateral and make application thereof to the Obligations in the order set forth in the Credit Agreement, and (ii) Lender
or its nominee may exercise (A) all voting, consent, corporate and other rights pertaining to the Pledged Collateral at any meeting of shareholders, partners or members, as the case may be, of
the relevant issuer or issuers of Pledged Collateral or otherwise and (B) any and all rights of conversion, exchange and subscription and any other rights, privileges or options pertaining to
the Pledged Collateral as if it were the absolute owner thereof (including the right to exchange at its discretion any and all of the Pledged Collateral upon the merger, consolidation, reorganization,
recapitalization or other fundamental change in the corporate structure of any issuer of Pledged Securities, the right to deposit and deliver any and all of the Pledged Collateral with any committee,
depositary, transfer agent, registrar or other designated agency upon such terms and conditions as Lender may determine), all without liability except to account for property actually received by it,
but Lender shall have no duty to Grantors to exercise any such right, privilege or option and shall not be responsible for any failure to do so or delay in so doing.

(b)   In
order to permit Lender to exercise the voting and other consensual rights which it may be entitled to exercise pursuant hereto and to receive all dividends and other
distributions which it may be entitled to receive hereunder, (i) upon the occurrence and during the continuance of an Event of Default, each Grantor shall promptly execute and deliver (or cause
to be executed and delivered) to Lender all such proxies, dividend payment orders and other instruments as Lender may from time to time reasonably request and (ii) without limiting the effect
of clause (i) above, each Grantor hereby grants to Lender an irrevocable proxy to vote all or any part of the Pledged Collateral owned by such Grantor and to exercise all other rights, powers,
privileges and remedies to which a holder of the Pledged Collateral would be entitled (including giving or withholding written consents of shareholders, partners or members, as the case may be,
calling special meetings of shareholders, partners or members, as the case may be, and voting at such meetings), which proxy shall be effective, automatically and without the necessity of any action
(including any transfer of any Pledged Collateral on the

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record
books of the issuer thereof) by any other person (including the issuer of such Pledged Collateral or any officer or agent thereof) during the continuance of an Event of Default and which proxy
shall only terminate upon the payment in full of the Guaranteed Obligations (in respect of Loans and Reimbursement Obligations and interest and fees thereon and expenses related thereto) and the
termination of the Commitment.

(c)   Each
Grantor hereby expressly authorizes and instructs each issuer of any Pledged Collateral pledged hereunder by such Grantor to (i) comply with any instruction
received by it from Lender in writing that (A) states that an Event of Default has occurred and is continuing and (B) is otherwise in accordance with the terms of this Agreement, without
any other or further instructions from such Grantor, and such Grantor agrees that such issuer shall be fully protected in so complying and (ii) unless otherwise expressly permitted hereby, pay
any dividends or other payments with respect to the Pledged Collateral directly to an Approved Deposit Account approved for such purpose by Lender.

Section 5.3Sale of Pledged Collateral.

(a)   Each
Grantor recognizes that Lender may be unable to effect a sale of any or all the Pledged Collateral by reason of certain prohibitions contained in the Securities Act
and applicable state securities laws or otherwise or may determine that a public sale is impracticable or not commercially reasonable and, accordingly, may resort to one or more private sales thereof
to a restricted group of purchasers which will be obliged to agree, among other things, to acquire such securities for their own account for investment and not with a view to the distribution or
resale thereof. Each Grantor acknowledges and agrees that any such private sale may result in prices and other terms less favorable than if such sale were a public sale and, notwithstanding such
circumstances, agrees that any such private sale shall be deemed to have been made in a commercially reasonable manner. Lender shall be under no obligation to delay a sale of any of the Pledged
Collateral for the period of time necessary to permit the issuer thereof to register such securities for public sale under the Securities Act, or under applicable state securities laws, even if such
issuer would agree to do so.

(b)   Each
Grantor agrees to use its commercially reasonable efforts to do or cause to be done all such acts as may be necessary to make such sale or sales of all or any
portion of the Pledged Collateral owned by it pursuant to thisSection 5.3valid and binding and in compliance with any and all applicable
Requirements of Law;provided, however,that such Grantor shall not be obligated to register any portion of the Pledged Collateral under the provisions
of the Securities Act. Each Grantor further agrees that a breach of any of the covenants contained in thisSection 5.3will cause irreparable
injury to Lender, that Lender has no adequate remedy at law in respect of such breach and, as a consequence, that each and every covenant contained in this Section 5.3shall be specifically
enforceable against such Grantor, and such Grantor hereby waives and agrees not to assert any defenses against
an action for specific performance of such covenants except for a defense that no Event of Default has occurred and is continuing.

Section 5.4Deficiency.Each Grantor shall remain liable for any
deficiency if
the proceeds of any sale or other disposition of the Collateral are insufficient to pay the Guaranteed Obligations and the fees and disbursements of any attorneys employed by Lender to collect such
deficiency.

ARTICLE VI

POWER OF ATTORNEY

Section 6.1Lender's Appointment as Attorney-in-Fact.

(a)   Each
Grantor hereby irrevocably constitutes and appoints Lender and any officer or agent thereof, with full power of substitution, as its true and lawful
attorney-in-fact with full irrevocable power and authority in the place and stead of such Grantor and in the name of such Grantor or in its own name, for the purpose of
carrying out the terms of this Agreement, to take any and all appropriate action and to execute any and all documents and instruments which may be necessary or desirable to accomplish the purposes of
this Agreement, and, without limiting the generality of the foregoing, such Grantor hereby gives Lender the power and right, on behalf of such Grantor, without notice to or assent by such Grantor, to
do any or all of the following:

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Anything
in thisSection 6.1(a)to the contrary notwithstanding, Lender agrees that it will not exercise any rights under the power of attorney
provided for in thisSection 6.1(a)unless an Event of Default shall have occurred and be continuing.

(b)   If
any Grantor fails to perform or comply with any of its agreements contained herein, and such failure constitutes an Event of Default, Lender (so long as such Event of
Default is continuing), at its option, but without any obligation so to do, may perform or comply, or otherwise cause performance or compliance, with such agreement.

(c)   The
expenses of Lender incurred in connection with actions undertaken as provided in thisSection 6.1, together
with interest thereon at a rate per annum equal to the Applicable Rate at which interest would then be payable on past due Loans under the Credit Agreement, from the date of payment by Lender to the
date reimbursed by Grantors, shall be payable by Grantors to Lender on demand.

(d)   Each
Grantor hereby ratifies all that said attorneys shall lawfully do or cause to be done by virtue hereof. All powers, authorizations and agencies contained in this
Agreement are coupled with an interest and are irrevocable until this Agreement is terminated and the security interests created hereby are released.

Section 6.2Duty of Lender.Lender's sole duty with respect to the custody,

safekeeping and physical preservation of the Collateral in its possession shall be to deal with it in the same manner as Lender deals with similar property for its own account. Subject to applicable
law, neither Lender nor any of its officers, directors, employees or agents shall be liable for failure to demand, collect or realize upon any of the Collateral or for any delay in doing so or shall
be under any obligation to sell or otherwise dispose of any Collateral upon the request of any Grantor or any other Person or to take any other action whatsoever with regard to the Collateral or any
part thereof. The powers conferred on Lender hereunder are solely to protect Lender's interest in the Collateral and shall not impose any duty upon Lender to exercise any such powers. Lender shall be
accountable only for amounts that Lender actually receives as a result of the exercise of such powers, and neither Lender nor any of its officers, directors, employees or agents shall be responsible
to Grantors for any act or failure to act hereunder.

Section 6.3Execution of Financing Statements.Each Grantor authorizes
Lender to
file or record financing statements and other filing or recording documents or instruments with respect to the Collateral in such form and in such offices as Lender reasonably determines appropriate
to perfect the security interests of Lender under this Agreement. A photographic or other reproduction of this Agreement shall be sufficient as a financing statement or other filing or recording
document or instrument for filing or recording in any jurisdiction.

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ARTICLE VII

MISCELLANEOUS

Section 7.1Amendments in Writing.None of the terms or provisions of this
Agreement may be waived, amended, supplemented or otherwise modified except in accordance with Section 10.1 of the Credit Agreement.

Section 7.2Notices.All notices, requests and demands to or upon Lender
or
Grantors hereunder shall be effected in the manner provided for in Section 10.6 of the Credit Agreement.

Section 7.3No Waiver by Course of Conduct; Cumulative Remedies.Lender
shall not
by any act (except by a written instrument pursuant to Section 7.1), delay, indulgence, omission or otherwise be deemed to have waived any right or remedy hereunder or to have acquiesced in any
Default or Event of Default. No failure to exercise, nor any delay in exercising, on the part of Lender any right, power or privilege hereunder shall operate as a waiver
thereof. No single or partial exercise of any right, power or privilege hereunder shall preclude any other or further exercise thereof or the exercise of any other right, power or privilege. A waiver
by Lender of any right or remedy hereunder on any one occasion shall not be construed as a bar to any right or remedy which Lender would otherwise have on any future occasion. The rights and remedies
herein provided are cumulative, may be exercised singly or concurrently and are not exclusive of any other rights or remedies provided by law.

Section 7.4Successors and Assigns.This Agreement shall be binding upon
the
successors and assigns of Grantors and shall inure to the benefit of Lender and its successors and assigns; provided, however, that no Grantor may assign, transfer or delegate any of its rights or
obligations under this Agreement without the prior written consent of Lender.

Section 7.5Counterparts.This Agreement may be executed by one or more of
the
parties to this Agreement on any number of separate counterparts (including by telecopy), and all of said counterparts taken together shall be deemed to constitute one and the same agreement.

Section 7.6Severability.Any provision of this Agreement which is
prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions hereof, and any
such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction.

Section 7.7Section Headings.The Article and Section titles contained in
this
Agreement are and shall be without substantive meaning or content of any kind whatsoever and are not part of the agreement of the parties hereto.

Section 7.8Entire Agreement.This Agreement together with the other Loan
Documents represents the entire agreement of the parties and supersedes all prior agreements and understandings relating to the subject matter hereof.

Section 7.9Governing Law.This agreement and the
rights
and obligations of the parties hereto shall be governed by, and construed and interpreted in accordance with, the law of the state of New York.

Section 7.10Release of Collateral; Termination.

(a)   Upon
termination of the Commitment and payment and satisfaction in full of all Loans, Reimbursement Obligations and all other Guaranteed Obligations which have matured
and which are then due and payable, the Collateral shall automatically be released from the Lien created hereby and this Agreement and all obligations (other than those expressly stated to survive
such termination) of Lender and Grantors hereunder shall immediately terminate, all without delivery of any instrument or performance of any act by any party, and all rights to the Collateral shall
revert to Grantors. At the request and sole expense of any Grantor following any such termination, Lender shall deliver to such Grantor any Collateral of such Grantor held by Lender hereunder and
execute and deliver to such Grantor such documents as such Grantor shall reasonably request to evidence such termination.

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(b)   If
any of the Collateral shall be sold or disposed of by any Grantor in a transaction permitted by the Credit Agreement or the Subsidiary Guarantee (including by
operation of Lender's written consent or waiver), the Collateral so sold or disposed of shall be automatically released from the Lien created hereby and, in connection therewith, Lender, at the
request and sole expense of such Grantor, shall execute and deliver to such Grantor all releases or other documents reasonably necessary or desirable for the release of the Lien created hereby on such
Collateral.

Section 7.11Reinstatement.Each Grantor further agrees that, if any
payment made
by such Grantor or any other Person and applied to the Guaranteed Obligations is at any time annulled, avoided, set aside, rescinded, invalidated, declared to be fraudulent or preferential or
otherwise required to be refunded or repaid, or the proceeds of Collateral are required to be returned by Lender to such person, its estate, trustee, receiver or any other party, including such
Grantor, under any bankruptcy law, state or federal law, common law or equitable cause, then, to the extent of such payment or repayment, any Lien or other Collateral securing such liability shall be
and remain in full force and effect, as fully as if such payment had never been made or, if prior thereto the Lien granted hereby or other Collateral securing such liability hereunder shall have been
released or terminated), such Lien or other Collateral shall be reinstated in full force and effect, and such prior release or termination shall not diminish, release, discharge, impair or otherwise
affect any Lien or other Collateral securing the obligations of such Grantor in respect of the amount of such payment.

[SIGNATURE
PAGES FOLLOW]

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EXHIBIT 10.28.1

Revolving Credit Agreement

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IN
WITNESS WHEREOF, each of the undersigned has caused this Subsidiary Pledge Agreement to be duly executed and delivered as of the date first above written.

|                                              |  |                   |  |                                                      |  | UNION CARBIDE SUBSIDIARY C, INC.               
|--------------------------------------------- |  | ----------------- |  | ---------------------------------------------------- |  | -----------------------------------------------
|                                              |  |                   |  |                                                      |  | By:                                            
|                                              |  |                   |  |                                                      |  | Name:                                          
|                                              |  |                   |  |                                                      |  | Title:                                         
|                                              |  |                   |  |                                                      |  | UCMG LLC                                       
|                                              |  |                   |  |                                                      |  | By:                                            
|                                              |  |                   |  |                                                      |  | Name:                                          
|                                              |  |                   |  |                                                      |  | Title:                                         
|                                              |  |                   |  |                                                      |  | CATALYSTS, ADSORBENTS AND PROCESS SYSTEMS, INC.
|                                              |  |                   |  |                                                      |  | By:                                            
|                                              |  |                   |  |                                                      |  | Name:                                          
|                                              |  |                   |  |                                                      |  | Title:                                         
|ACCEPTED AND AGREED:
THE DOW CHEMICAL COMPANY |  |                   |  |                                                     
|By:                                           |  | /s/J. P. REINHARD |  |                                                      |  |                                                
|                                              |  | Name:             |  | J. P. Reinhard                                       |  |                                                
|                                              |  | Title:            |  | Executive Vice President and
Chief Financial Officer |  |                                                

45

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EXHIBIT 10.28.1

Revolving Credit Agreement

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Schedule 1  State of Organization; Principal Place of Business

|1. |  | Union Carbide Subsidiary C, Inc.               
|-- |  | -----------------------------------------------
|   |  | Jurisdiction of organization:                  
|   |  | I.R.S. Employer Identification Number:         
|   |  | Principal place of business:                   
|2. |  | UCMG LLC                                       
|   |  | Jurisdiction of organization:                  
|   |  | I.R.S. Employer Identification Number:         
|   |  | Principal place of business:                   
|3. |  | Catalysts, Adsorbents and Process Systems, Inc.
|   |  | Jurisdiction of organization:                  
|   |  | I.R.S. Employer Identification Number:         
|   |  | Principal place of business:                   

46

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EXHIBIT 10.28.1

Revolving Credit Agreement

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Schedule 2
Pledged Collateral1

|Issuer                                |  | Holder   |  | Shares  |  | Class (if
known) |  | % Ownership
|------------------------------------- |  | -------- |  | ------- |  | ---------------- |  | -----------
|Optimal Glycols (Malaysia) Sdn. Bhd.* |  | UCMG LLC |  | 128,518 |  | Ordinary         |  | 50         

None.

|Issuer                       |  | Holder                                          |  | Shares |  | Class (if
known) |  | % Ownership
|---------------------------- |  | ----------------------------------------------- |  | ------ |  | ---------------- |  | -----------
|Univation Technologies, LLC* |  | Union Carbide Subsidiary C, Inc.                |  |        |  |                  |  | 50         
|UOP LLC                      |  | Catalysts, Adsorbents and Process Systems, Inc. |  |        |  |                  |  | 50         

None.

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EXHIBIT 10.28.1

Revolving Credit Agreement

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Schedule 3
Required Action for Perfection

1.    Union
Carbide Subsidiary C, Inc. must obtain the consent of Exxon Chemical Licensing Company in order to pledge its interest in Univation Technologies, LLC
("Univation") to TDCC.

2.    UCMG
LLC must obtain the consent of Petroliam Nasional Berhad (Petronas) in order pledge its shares of Optimal Glycols (Malaysia) Sdn. Bhd. ("Optimal
Glycols") to TDCC.

3.    Catalysts,
Adsorbents and Process Systems, Inc. must obtain the consent of EM Sector Holdings Inc. in order to pledge its interest in UOP LLC
("UOP") to TDCC.

4.    Once
each of the above consents has been obtained, the pledge must be made and TDCC must maintain possession of the certificated interests.

5.    UCC-1's
must be filed for non-certificated interests.

6.    Any
consent required in the financing documents related to (i) EQUATE Petrochemical Company K.S.C., (ii) Asian Acetyls Co., Ltd., (iii) UOP,
(iv) Nippon Unicar Co., Ltd. (v) Univation and (vi) Optimal Glycols, Optimal Chemicals (Malaysia) Sdn. Bhd. and Optimal Olefins (Malaysia) Sdn. Bhd.

7.    Such
actions as foreign counsel advises are necessary for the perfection of interests in non-U.S. entities.

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