<PAGE>   1
                                                                     EXHIBIT 3.1


                          SECOND AMENDED AND RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                                   CONOCO INC.

                  CONOCO INC., a Delaware corporation, (hereinafter the 
"Corporation") hereby certifies as follows:

                  1.     The name of the Corporation is CONOCO INC.  The
original Certificate of Incorporation of the Corporation was filed with the
Secretary of State of the State of Delaware on November 2, 1995 under the name
Conoco Energy Company.

                  2.     This Second Amended and Restated Certificate of
Incorporation of CONOCO INC. amends and restates the provisions of the
Certificate of Incorporation of the Corporation, filed with the Secretary of
State of the State of Delaware on November 2, 1995 and as amended on July 24,
1998 and October 19, 1998, and was duly adopted in accordance with Sections 242
and 245 of the General Corporation Law of the State of Delaware (the "DGCL") and
by written consent of its Stockholder in accordance with Section 228 of the DGCL
and the Amended and Restated Certificate of Incorporation as heretofore amended.

                  3.     On October 19, 1998, the Corporation filed a
Certificate of Designation, Preferences and Rights of a series of Preferred
Stock designated "Series A Junior Participating Preferred Stock"; no shares of
such series of Preferred Stock have been issued. Pursuant to the authority
granted to the Board of Directors of the Corporation by Section 151(g) of the
Delaware General Corporation Law, on October 20, 1998 the Board of Directors of
the Corporation adopted the following resolution amending the terms of such
series of Preferred Stock:

         RESOLVED, that pursuant to the authority granted to the Board of
         Directors of the Corporation by Section 151(g) of the Delaware General
         Corporation Law, the terms of the series of Preferred Stock, par value
         $.01 per share, of the Corporation designated "Series A Junior
         Participating Preferred Stock" are hereby amended by replacing the date
         "October 18, 1998" in Section 2(A) of the Certificate of Designation,
         Preferences and Rights for such Preferred Stock with "October 22,
         1998".

         Accordingly, effective upon the filing of this Second Amended and
Restated Certificate of Incorporation with the Secretary of State of the State
of Delaware (such time referred to herein as the "Effective Time"), the
Certificate of Designation, Preferences and Rights of Series A Preferred Stock
shall be amended in accordance with the foregoing resolution.

                  4.     At the Effective Time, a reclassification (the
"Reclassification") of the Corporation's Class B Common Stock, par value $.01
per share (the "Class B Common Stock") shall occur as follows: the 455,500,000
(the "Initial Number") issued and outstanding shares of the Class B Common Stock
shall be reclassified, without any action on the part of the holder thereof,
into 430,000,000 (the "Aggregate Reclassified Number") shares of Class B Common
Stock, and accordingly each share of Class B Common Stock shall be reclassified
into a number of shares of Class B Common Stock equal to 430 divided by 455.5
(the "Reclassified Per Share Number"). From and after the Effective Time, the
holders of outstanding certificates which immediately prior to the Effective
Time represented the number of shares of Class B Common Stock prior to giving
effect to the Reclassification shall cease to have any rights with respect to
such shares and, until such certificates are surrendered and exchanged in the
manner provided for herein, each such certificate shall, after the Effective
Time, be deemed to represent only the number of shares of Class B Common Stock
after giving effect to the Reclassification. From and after the Effective Time,
the Corporation shall be entitled to treat any unsurrendered certificates as
evidencing the ownership of the number of shares of Class B Common Stock after
giving effect to the Reclassification, notwithstanding the failure to surrender
such certificates. Upon the surrender to the Corporation of all certificates
held by a holder of shares of Class B Common Stock, together with such stock
transfer powers and other documents reasonably requested by the Corporation, the
holder of such certificates shall receive therefor a certificate for the number
of shares of Class B Common Stock after giving effect to the Reclassification.
The rights, preferences and powers of the Class B Common Stock and the Class A
Common Stock shall be unaffected by the Reclassification.

                  The Corporation's Amended and Restated Certificate of
Incorporation, as heretofore amended, is hereby restated, integrated and amended
to read in its entirety as follows (with references herein to Certificate of
Incorporation to mean this Second Amended and Restated Certificate of
Incorporation):
                    
                  FIRST: The name of the Corporation is Conoco
Inc. (hereinafter the "Corporation").

                  SECOND: The address of the registered office of the
Corporation in the State of Delaware is 1209 Orange Street, in the City of
Wilmington, County of New Castle. The name of its registered agent at that
address is The Corporation Trust Company.

                  THIRD: The purpose of the Corporation is to engage in any
lawful act or activity for which a corporation may be organized under the
General Corporation Law of the State of Delaware as set forth in Title 8 of the
Delaware Code (the "GCL").

                  FOURTH: A. The total number of shares of stock that the
Corporation shall have authority to issue is 4,850,000,000 (four billion eight
hundred fifty million) of which (i) 3,000,000,000 (three billion) shares shall
be shares of Class A Common Stock, par value $.01 per share (the "Class A Common
Stock"), and 1,600,000,000 (one billion six hundred million) shares shall be
shares of Class B Common Stock, par value $.01 per share (the "Class B Common
Stock") (the Class A Common Stock and the Class B Common Stock being
collectively referred to herein as the "Common Stock"), and (ii) 250,000,000
(two hundred and fifty million) shares shall be shares of Preferred Stock, par
value $.01 per share (the "Preferred Stock").

         B. Preferred Stock The Board of Directors is expressly authorized to
provide for the issuance of all or any shares of the Preferred Stock in one or
more classes or series, and to fix for each such class or series the voting
powers (if any) and such distinctive designations, preferences and relative,
participating, optional or other special rights and such qualifications,
limitations or restrictions thereof, as shall be stated
<PAGE>   2



and expressed in the resolution or resolutions adopted by the Board of Directors
providing for the issuance of such class or series and as may be permitted by
the GCL, including, without limitation, the authority to provide that any such
class or series may be (i) subject to redemption at such time or times and at
such price or prices; (ii) entitled to receive dividends (which may be
cumulative or non-cumulative) at such rates, on such conditions, and at such
times, and payable in preference to, or in such relation to, the dividends
payable on any other class or classes or any other series; (iii) entitled to
such rights upon the dissolution of, or upon any distribution of the assets of,
the Corporation; or (iv) convertible into, or exchangeable for, shares of any
other class or classes of stock, or of any other series of the same or any other
class or classes of stock, of the Corporation at such price or prices or at such
rates of exchange and with such adjustments; all as may be stated in such
resolution or resolutions.

         C. Common Stock The following is a statement of the relative powers,
preferences and participating, optional or other special rights, and the
qualifications, limitations and restrictions of the Class A Common Stock and
Class B Common Stock of the Corporation:

            (1) Except as otherwise set forth below in this Article FOURTH, the 
relative powers, preferences and participating, optional or other special
rights, and the qualifications, limitations or restrictions of the Class A
Common Stock and Class B Common Stock shall be identical in all respects.

            (2) Subject to the rights of the holders of Preferred Stock, and 
subject to any other provisions of this Certificate of Incorporation, holders of
Class A Common Stock and Class B Common Stock shall be entitled to receive such
dividends and other distributions in cash, stock of any corporation (other than
Common Stock of the Corporation) or property of the Corporation as may be
declared thereon by the Board of Directors from time to time out of assets or
funds of the Corporation legally available therefor and shall share equally on a
per share basis in all such dividends and other distributions. In the case of
dividends or other distributions payable in Common Stock, including
distributions pursuant to stock splits or divisions of Common Stock of the
Corporation, 



                                       2
<PAGE>   3


only shares of Class A Common Stock shall be paid or distributed with respect to
Class A Common Stock and only shares of Class B Common Stock shall be paid or
distributed with respect to Class B Common Stock. The number of shares of Class
A Common Stock and Class B Common Stock so distributed on each share shall be
equal in number. Neither the shares of Class A Common Stock nor the shares of
Class B Common Stock may be reclassified, subdivided or combined unless such
reclassification, subdivision or combination occurs simultaneously and in the
same proportion for each class.

            (3) (a) At every meeting of the stockholders of the Corporation 
every holder of Class A Common Stock shall be entitled to one vote in person or
by proxy for each share of Class A Common Stock standing in his or her name on
the transfer books of the Corporation, and every holder of Class B Common Stock
shall be entitled to five votes in person or by proxy for each share of Class B
Common Stock standing in his or her name on the transfer books of the
Corporation in connection with the election of directors and all other matters
submitted to a vote of stockholders. Except as may be otherwise required by law
or by this Certificate of Incorporation, the holders of Class A Common Stock and
Class B Common Stock shall vote together as a single class and their votes shall
be counted and totaled together, subject to any voting rights which may be
granted to holders of Preferred Stock, on all matters submitted to a vote of
stockholders of the Corporation. Notwithstanding any other provision of this
Certificate of Incorporation to the contrary, holders of Class A Common Stock
shall not be eligible to vote on any alteration or change in the powers, 
preferences, or special rights of the Class B Common Stock that would not
adversely affect the rights of the Class A Common Stock; provided that, for the
foregoing purposes, any provision for the voluntary, mandatory or other
conversion or exchange of the Class B Common Stock into or for Class A Common
Stock on a one for one basis shall be deemed not to adversely affect the rights
of the Class A Common Stock.

                (b) Except as otherwise provided by law, and subject to any 
rights of the holders of Preferred Stock, the provisions of this Certificate of
Incorporation shall not be modified, revised, altered or amended, repealed or
rescinded in whole or in part, without the 



                                       3
<PAGE>   4



approval of a majority of the votes entitled to be cast by the holders of the
Class A Common Stock and the Class B Common Stock, voting together as a single
class (except as otherwise provided in paragraph (C)(3)(a) above); provided,
however, that with respect to any proposed amendment of this Certificate of
Incorporation which would alter or change the powers, preferences or special
rights of the shares of Class A Common Stock or Class B Common Stock so as to
affect them adversely, the approval of a majority of the votes entitled to be
cast by the holders of the shares affected by the proposed amendment, voting
separately as a class, shall be obtained in addition to the approval of a
majority of the votes entitled to be cast by the holders of the Class A Common
Stock and the Class B Common Stock voting together as a single class as
hereinbefore provided. The affirmative vote of shares representing (x) not less
than 66 2/3% (or, from and after the Second Trigger Date (as defined in
paragraph (C) of Article FIFTH), 80%) of the votes entitled to be cast by the
Voting Stock and (y) in addition, from and after the First Trigger Date (as
defined in paragraph (C) of Article FIFTH) (if there are at such time any shares
of Class B Common Stock outstanding), a majority of the votes entitled to be
cast by the holders of each class of Common Stock, voting separately by class,
shall be required to alter, amend or adopt any provision inconsistent with or
repeal Article FIFTH or Article EIGHTH or any provision of this paragraph
(C)(3)(b). "Voting Stock" shall mean the then outstanding shares of capital
stock entitled to vote generally on the election of directors and shall exclude
any class or series of capital stock only entitled to vote in the event of
dividend arrearages thereon, whether or not at the time of determination there
are any such dividend arrearages. To the fullest extent permitted by law, any
increase in the authorized number of shares of any class or classes of stock of
the Corporation or creation, authorization or issuance of any securities
convertible into, or warrants, options or similar rights to purchase, acquire or
receive, shares of any such class or classes of stock shall be deemed not to
affect adversely the powers, preferences or special rights of the shares of
Class A Common Stock or Class B Common Stock.

                (c) Every reference in this Certificate of Incorporation to a 
majority or other proportion of shares, or a majority or other proportion of the
votes of 



                                       4
<PAGE>   5


shares, of Voting Stock, Common Stock, Class A Common Stock, or Class B Common
Stock shall refer to such majority or other proportion of the votes to which
such shares of Voting Stock, Common Stock, Class A Common Stock or Class B
Common Stock are entitled.

                (d) At any meeting of stockholders, the presence in person or by
proxy of the holders of shares entitled to cast a majority of all the votes
which could be cast at such meeting by the holders of all of the outstanding
shares of stock of the Corporation entitled to vote on every matter that is to
be voted on at such meeting shall constitute a quorum.

            (4) In the event of any dissolution, liquidation or winding up of 
the affairs of the Corporation, whether voluntary or involuntary, after payment
in full of the amounts required to be paid to the holders of Preferred Stock,
the remaining assets and funds of the Corporation shall be distributed pro rata
to the holders of Common Stock, and the holders of Class A Common Stock and the
holders of Class B Common Stock will be entitled to receive the same amount per
share in respect thereof. For purposes of this paragraph (C)(4), the voluntary
sale, conveyance, lease, exchange or transfer (for cash, shares of stock,
securities or other consideration) of all or substantially all of the assets of
the Corporation or a consolidation or merger of the Corporation with one or more
other corporations (whether or not the Corporation is the corporation surviving
such consolidation or merger) shall not be deemed to be a liquidation, 
dissolution or winding up, voluntary or involuntary.

            (5) Except as shall otherwise be approved by a majority of the votes
entitled to be cast by the holders of each class of Common Stock voting
separately as a class, in case of any reorganization or any consolidation of the
Corporation with one or more other corporations or a merger of the Corporation
with another corporation in which shares of Class A Common Stock or Class B
Common Stock are converted into (or entitled to receive with respect thereto)
shares of stock and/or other securities or property (including cash), each
holder of a share of Class A Common Stock shall be entitled to receive with
respect to such share the same kind and amount of shares of stock and other
securities and property (including cash) receivable upon such reorganization,
consolidation 



                                       5
<PAGE>   6


or merger by a holder of a share of Class B Common Stock and each holder of a
share of Class B Common Stock shall be entitled to receive with respect to such
share the same kind and amount of shares of stock and other securities and
property (including cash) receivable upon such reorganization, consolidation or
merger by a holder of a share of Class A Common Stock. In the event that the
holders of Class A Common Stock (or of Class B Common Stock) are granted rights
to elect to receive one of two or more alternative forms of consideration, the
foregoing provision shall be deemed satisfied if holders of Class A Common Stock
and holders of Class B Common Stock are granted substantially identical election
rights.

            (6) (a) Prior to the date on which shares of Class B Common
Stock are transferred to stockholders of the DuPont Company in a Tax-Free
Spin-Off (as defined in paragraph (C)(6)(b) below), each record holder of shares
of Class B Common Stock may convert any or all of such shares into an equal
number of shares of Class A Common Stock by surrendering the certificates for
such shares, accompanied by any payment required for documentary, stamp or
similar issue or transfer taxes and by a written notice by such record holder to
the Corporation stating that such record holder desires to convert such shares
of Class B Common Stock into the same number of shares of Class A Common Stock
including for the purpose of the sale or other disposition of such shares of
Class A Common Stock, and requesting that the Corporation issue all of such
shares of Class A Common Stock to persons named therein, setting forth the
number of shares of Class A Common Stock to be issued to each such person and
the denominations in which the certificates therefor are to be issued. To the
extent permitted by law, such voluntary conversion shall be deemed to have been
effected at the close of business on the date of such surrender. Following a
Tax-Free Spin-Off, shares of Class B Common Stock shall no longer be convertible
into shares of Class A Common Stock.

                (b) Prior to a Tax-Free Spin-Off, each share of Class B Common 
Stock shall automatically be converted into one share of Class A Common Stock
upon the transfer of such share if, after such transfer, such share is not
beneficially owned by DuPont. Shares of Class B Common stock shall not convert
into shares of Class A Common Stock (i) in any transfer effected in 



                                       6
<PAGE>   7


connection with a distribution of Class B Common Stock to  security holders of
the DuPont Company in a transaction (including any distribution in exchange for
shares of capital stock or securities of the DuPont Company) in tended to
qualify as a tax-free distribution under Section 355 of the Internal Revenue
Code of 1986, as amended (the "Code"), or any successor provision (a "Tax-Free
Spin-Off") or (ii) in any transfer after a Tax-Free Spin- Off. For purposes of
this paragraph (C)(6), a Tax-Free Spin-Off shall be deemed to have occurred at
the time shares are first transferred to stockholders of the DuPont Company
following receipt of an affidavit described in clause (iii) of the first
sentence of paragraph (C)(6)(d) below. For purposes of this paragraph (C)(6),
each reference to a "person" shall be deemed to include not only a natural
person, but also a corporation, partnership, joint venture, association, or
legal entity of any kind; each reference to a "natural person" (or to a "record
holder" of shares, if a natural person) shall be deemed to include in his or her
representative capacity a guardian, committee, executor, administrator or other
legal representative of such natural person or record holder.

         For purposes of this Certificate of Incorporation:

                  1.       The "DuPont Company" shall mean E.I. du Pont de
                           Nemours & Company, Inc., a Delaware corporation, and
                           all its successors by way of merger, consolidation or
                           sale of all or substantially all of its assets;

                  2.       The term "subsidiary" shall mean, as to any person or
                           entity, a corporation, partnership, joint venture,
                           association or other entity in which such person or
                           entity beneficially owns (directly or indirectly) 50%
                           or more of the outstanding voting stock, voting
                           power, partnership interests or similar voting
                           interests;

                  3.       "DuPont" shall mean the DuPont Company and all its
                           subsidiaries, but shall not include the Corporation
                           and its subsidiaries; and



                                       7
<PAGE>   8

                  4.       "affiliate" and "beneficial ownership" shall have the
                           respective meanings given to such terms in Rule 13d-3
                           promulgated under the Securities Exchange Act of
                           1934, as amended.

                  Each share of Class B Common Stock shall automatically be
converted into one share of Class A Common Stock on the date on which the
outstanding shares of Class B Common Stock owned by DuPont represent less than
50% of the aggregate number of shares of the then out standing Common Stock,
provided that a Tax-Free Spin-Off has not occurred. For the avoidance of doubt,
paragraph (C)(3)(c) of this Article FOURTH shall not apply to the preceding
sentence.

                  The Corporation will provide notice of any automatic
conversion of all outstanding shares of Class B Common Stock to holders of
record of the Common Stock as soon as practicable following such conversion;
provided, however, that the Corporation may satisfy such notice requirement by
providing such notice prior to such conversion. Such notice shall be provided
by mailing notice of such conversion first class postage prepaid, to each holder
of record of the Common Stock, at such holder's address as it appears on the
transfer books of the Corporation; provided, however, that no failure to give
such notice nor any defect therein shall affect the validity of the automatic
conversion of any shares of Class B Common Stock. Each such notice shall state,
as appropriate, the following:

                                    (i) the automatic conversion date;

                                    (ii) that all outstanding shares of Class B
                           Common Stock are automatically converted;

                                    (iii) the place or places where certificates
                           for such shares may be surrendered in exchange for
                           certificates representing Class A Common
                           Stock.

                  Immediately upon such conversion, the rights of the holders of
shares of Class B Common Stock as such 



                                       8
<PAGE>   9


shall cease and such holders shall be treated for all purposes as having become
the record owners of the shares of Class A Common Stock issuable upon such
conversion; provided, however, that such persons shall be entitled to receive
when paid any dividends declared on the Class B Common Stock as of a record date
preceding the time of such conversion and unpaid as of the time of such 
conversion, subject to paragraph (C)(6)(f) below.

                           (c) Prior to a Tax-Free Spin-Off, holders of shares 
of Class B Common Stock may (i) sell or other wise dispose of or transfer any or
all of such shares held by them, respectively, only in connection with a
transfer which meets the qualifications of paragraph (C)(6)(d) below, and under
no other circumstances, or (ii) convert any or all of such shares into shares of
Class A Common Stock, including for the purpose of effecting the sale or
disposition of such shares of Class A Common Stock to any person as provided in
paragraph (C)(6)(a) above. Prior to a Tax-Free Spin-Off, no one other than those
persons in whose names shares of Class B Common Stock become registered on the
original stock ledger of the Corporation by reason of their record ownership of
shares of common stock of the Corporation which are reclassified into shares of
Class B Common Stock as provided in paragraph (C)(6)(l) below, or transferees
or successive transferees who receive shares of Class B Common Stock in
connection with a transfer which meets the qualifications set forth in paragraph
(C)(6)(d) below, shall by virtue of the acquisition of a certificate for shares
of Class B Common Stock have the status of an owner or holder of shares of Class
B Common Stock or be recognized as such by the Corporation or be other wise
entitled to enjoy for his or her own benefit the special rights and powers of a
holder of shares of Class B Common Stock.

                  Holders of shares of Class B Common Stock may at any and all
times transfer to any person the shares of Class A Common Stock issuable upon
conversion of such shares of Class B Common Stock.

                           (d) Prior to a Tax-Free Spin-Off, shares of Class B 
Common Stock shall be transferred on the books of the Corporation and a new
certificate therefor issued, upon presentation at the office of the Secretary of
the Corporation (or at such additional place or places as may 



                                       9
<PAGE>   10

from time to time be designated by the Secretary or any Assistant Secretary of
the Corporation) of the certificate for such shares, in proper form for transfer
and accompanied by all requisite stock transfer tax stamps, only if such
certificate when so presented shall also be accompanied by any one of the
following:

                                    (i) an affidavit from the DuPont Company
                           stating that such certificate is being presented to
                           effect a transfer by the DuPont Company of such
                           shares to a subsidiary of the DuPont Company; or

                                    (ii) an affidavit from the DuPont Company
                           stating that such certificate is being presented to
                           effect a transfer by any subsidiary of the DuPont
                           Company of such shares to the DuPont Company or
                           another subsidiary of the DuPont Company; or

                                    (iii) an affidavit from the DuPont Company
                           stating that such certificate is being presented to
                           effect a transfer by the DuPont Company of such
                           shares to the stockholders of the DuPont Company in
                           connection with a Tax-Free Spin-Off.

                  Each affidavit of a record holder furnished pursuant to this
paragraph (C)(6)(d) shall be verified as of a date not earlier than five days
prior to the date of delivery thereof, and, where such record holder is a
corporation or partnership, shall be verified by an officer of the corporation
or by a general partner of the partnership, as the case may be.

                  If a record holder of shares of Class B Common Stock shall
deliver a certificate for such shares, endorsed by him or her for transfer or
accompanied by an instrument of transfer signed by him or her, to a person who
receives such shares in connection with a transfer which does not meet the
qualifications set forth in this paragraph (C)(6)(d), then such person or any
successive transferee of such certificate may treat such endorsement or
instrument as authorizing him or her on behalf of such 



                                       10
<PAGE>   11


record holder to convert such shares in the manner above provided for the
purpose of the transfer to himself or herself of the shares of Class A Common
Stock issuable upon such conversion, and to give on behalf of such record holder
the written notice of conversion above required, and may convert such shares of
Class B Common Stock accordingly.

                  If such shares of Class B Common Stock shall improperly have
been registered in the name of a person not meeting the qualifications set forth
in this paragraph (C)(6)(d)(or in the name of any successive transferee of
such certificate) and a new certificate therefor issued, such person or
transferee shall surrender such new certificate for cancellation, accompanied by
the written notice of conversion above required, in which case (A) such person
or transferee shall be deemed to have elected to treat the endorsement on (or
instrument of transfer accompanying) the certificate so delivered by such former
record holder as authorizing such person or transferee on behalf of such former
record holder so to convert such shares and so to give such notice, (B) the
shares of Class B Common Stock registered in the name of such former record
holder shall be deemed to have been surrendered for conversion for the purpose
of the transfer to such person or transferee of the shares of Class A Common
Stock issuable upon conversion, and (C) the appropriate entries shall be made
on the books of the Corporation to reflect such action.

                  In the event that the Board of Directors of the Corporation
(or any committee of the Board of Directors, or any officer of the Corporation,
designated for the purpose by the Board of Directors) shall determine, upon the
basis of facts not disclosed in any affidavit or other document accompanying the
certificate for shares of Class B Common Stock when presented for transfer, that
such shares of Class B Common Stock have been registered in violation of the
provisions of paragraph (C)(6), or shall determine that a person is enjoying for
his or her own benefit the special rights and powers of shares of Class B Common
Stock in violation of such provisions, then the Corporation shall take such
action at law or in equity as is appropriate under the circumstances. An
unforeclosed pledge made to secure a bona fide obligation shall not be deemed to
violate such provisions. Prior to the occurrence of a Tax-Free Spin-Off, no
transfer of 



                                       11

<PAGE>   12

title to shares of Class B Common Stock to a pledgee or other person (other than
DuPont) may occur without compliance with the foregoing provisions of this
paragraph (C)(6)(d).

                           (e) Prior to the occurrence of a Tax-Free Spin-Off, 
every certificate for shares of Class B Common Stock shall bear a legend on the
face thereof reading as follows:

         "The shares of Class B Common Stock represented by this certificate may
         not be transferred to any person in connection with a transfer that
         does not meet the qualifications set forth in paragraph (C)(6)(d) of
         Article FOURTH of the Certificate of Incorporation of this corporation
         and no person who receives such shares in connection with a transfer
         which does not meet the qualifications prescribed by paragraph
         (C)(6)(d) of said Article FOURTH is entitled to own or to be registered
         as the record holder of such shares of Class B Common Stock, but the
         record holder of this certificate may at such time and in the manner
         set forth in said Article FOURTH of the Certificate of Incorporation
         convert such shares of Class B Common Stock into the same number of
         shares of Class A Common Stock for purposes of effecting the sale or
         other disposition of such shares of Class A Common Stock to any person.
         Each holder of this certificate, by accepting the same, accepts and
         agrees to all of the foregoing."

                  Upon and after the transfer of shares in a Tax-Free Spin-Off,
shares of Class B Common Stock shall no longer bear the legend set forth above
in this paragraph (C)(6)(e).

                           (f) Upon any conversion of shares of Class B Common 
Stock into shares of Class A Common Stock pursuant to the provisions of this
paragraph (C)(6), any dividend, for which the record date or payment date shall
be subsequent to such conversion, which may have been declared on the shares of
Class B Common Stock so converted shall be deemed to have been declared, and
shall be payable, with respect to the shares of Class A Common Stock into or for
which such shares of Class B Common 



                                       12
<PAGE>   13


Stock shall have been so converted, and any such dividend which shall have been
declared on such shares payable in shares of Class B Common Stock shall be
deemed to have been declared, and shall be payable, in shares of Class A Common
Stock.

                           (g) The Corporation shall not reissue or resell any 
shares of Class B Common Stock which shall have been converted into shares of
Class A Common Stock pursuant to or as permitted by the provisions of this
paragraph (C)(6), or any shares of Class B Common Stock which shall have been
acquired by the Corporation in any other manner. The Corporation shall, from
time to time, take such appropriate action as may be necessary to retire such
shares and to reduce the authorized amount of Class B Common Stock accordingly.

                  The Corporation shall at all times reserve and keep available,
out of its authorized but unissued Common Stock, such number of shares of Class
A Common Stock as would become issuable upon the conversion of all shares of
Class B Common Stock then outstanding.

                           (h) In connection with any transfer or conversion of 
any stock of the Corporation pursuant to or as permitted by the provisions of
this paragraph (c)(6), or in connection with the making of any determination
referred to in this paragraph (c)(6):

                               (i) the Corporation shall be under no obligation 
                           to make any investigation of facts unless an 
                           officer, employee or agent of the Corporation
                           responsible for making such transfer or determination
                           or issuing Class A Common Stock pursuant to such
                           conversion has substantial reason to believe, or
                           unless the Board of Directors (or a committee of the
                           Board of Directors designated for the purpose)
                           determines that there is substantial reason to
                           believe, that any affidavit or other document is
                           incomplete or incorrect in a material respect or
                           that an investigation would disclose facts upon which
                           any determination referred to in para-




                                       13
<PAGE>   14

                           graph (C)(6)(f) above should be made, in either of
                           which events the Corporation shall make or cause to
                           be made such investigation as it may deem necessary
                           or desirable in the circumstances and have a
                           reasonable time to complete such investigation; and

                               (ii) neither the Corporation nor any director, 
                           officer, employee or agent of the Corporation shall
                           be liable in any manner for any action taken or
                           omitted in good faith.

                           (i) The Corporation will not be required to pay any 
documentary, stamp or similar issue or transfer taxes payable in respect of the
issue or delivery of shares of Class A Common Stock on the conversion of shares
of Class B Common Stock pursuant to this paragraph (C)(6), and no such issue or
delivery shall be made unless and until the person requesting such issue has
paid to the Corporation the amount of any such tax or has established, to the
satisfaction of the Corporation, that such tax has been paid.

                           (j) All rights to vote and all voting power 
(including, without limitation thereto, the right to elect directors) shall be
vested exclusively in the holders of Common Stock, voting together as a single
class, except as otherwise expressly provided in this Certificate of
Incorporation, in a Certificate of Designation with respect to any Preferred
Stock or as other wise expressly required by applicable law.

                           (k) No stockholder shall be entitled to exercise any 
right of cumulative voting.

                           (l) Immediately upon the effectiveness of this 
Certificate of Incorporation, each share of Class B Common Stock issued and
outstanding immediately prior to such effectiveness, shall be changed into and
reclassified into a number of shares of Class B Common Stock equal to 430 
divided by 455.5.

                  FIFTH:  A.  The business and affairs of the Corporation shall 
be managed by or under the direction of a Board of Directors initially
consisting of nine direc-



                                       14
<PAGE>   15


tors, the exact number of directors to be not less than six nor more than
fifteen as determined from time to time by resolution adopted by affirmative
vote of a majority of the entire Board of Directors. The directors shall be
divided into three classes, designated Class I, Class II and Class III. Each
class shall consist, as nearly as may be possible, of one-third of the total
number of directors constituting the entire Board of Directors. Class I
directors shall be elected initially for a one-year term, Class II directors
initially for a two-year term and Class III directors initially for a
three-year term. At each succeeding annual meeting of stockholders beginning in
1999, successors to the class of directors whose term expires at that annual
meeting shall be elected for a three-year term. If the number of directors is
changed, any increase or decrease shall be apportioned among the classes so as
to maintain the number of directors in each class as nearly equal as possible,
and any additional director of any class elected to fill a vacancy resulting
from an increase in such class shall hold office for a term that shall coincide
with the remaining term of that class, but in no case will a decrease in the
number of directors shorten the term of any incumbent director. A director shall
hold office until the annual meeting of the year in which his term expires and
until his successor shall be elected and shall qualify, subject, however, to
prior death, resignation or removal from office. Any vacancy on the Board of
Directors may be filled by a majority of the directors then in office, even if
less than a quorum, or by a sole remaining director or by stockholders if such
vacancy was caused by the action of stockholders (in which event such vacancy
may not be filled by the directors or a majority thereof).

            Any director elected to fill a vacancy not resulting from an
increase in the number of directors shall have the same remaining term as that
of his predecessor.

         B. Any director or the entire Board of Directors may be removed, with
or without cause, by the affirmative vote of shares representing a majority of
the votes entitled to be cast by the Voting Stock; provided, how ever that
during the Trigger Period (as defined in para graph (C) below), a director may
be removed, with or without cause, only by the affirmative vote of shares



                                       15
<PAGE>   16

representing not less than 66 2/3% of the votes entitled to be cast by the
Voting Stock; provided, further, however, that from and after the Second Trigger
Date (as defined in paragraph (C) below), a director may only be removed for
cause, such removal to be by the affirmative vote of the shares representing a
majority of the votes entitled to be cast by the Voting Stock. Unless the Board
of Directors has made a determination that removal is in the best interests of
the Corporation (in which case the following definition shall not apply),
"cause" for removal of a director shall be deemed to exist only if (i) the
director whose removal is proposed has been convicted, or when a director is
granted immunity to testify when another has been convicted, of a felony by a
court of competent jurisdiction and such conviction is no longer subject to
direct appeal; (ii) such director has been found by the affirmative vote of a
majority of the Directors then in office at any regular or special meeting of
the Board of Directors called for that purpose, or by a court of competent
jurisdiction to have been guilty of willful misconduct in the performance of his
duties to the Corporation in a matter of substantial importance to the
Corporation; or (iii) such director has been adjudicated by a court of
competent jurisdiction to be mentally incompetent, which mental incompetency
directly affects his ability as a director of the Corporation. Notwithstanding
the foregoing, whenever holders of outstanding shares of one or more series of
Preferred Stock are entitled to elect directors of the Corporation pursuant to
the provisions applicable in the case of arrearages in the payment of dividends
or other defaults contained in the resolution or resolutions of the Board of
Directors providing for the establishment of any such series, any such director
of the Corporation so elected may be removed in accordance with the provisions
of such resolution or resolutions.

         C. For purposes of this Certificate of Incorporation, "Trigger Period"
shall mean the period that begins on and after the day following the First
Trigger Date and ends on the Second Trigger Date: (i) "First Trigger Date" shall
mean the first date on which DuPont ceases to beneficially own shares
representing 50% or more of the votes entitled to be cast by the Voting Stock
and (ii) "Second Trigger Date" shall mean the first date on which DuPont ceases
to beneficially own shares representing 30% or more of the votes entitled to be
cast by the Voting Stock (First Trigger Date and Second Trigger Date, each a
"Trigger Date").

                                       16


<PAGE>   17




         D. Promptly upon becoming aware of the occurrence of a Trigger Date,
the Corporation shall promptly notify stockholders of such occurrence in any
reasonably practicable manner.

         E. The following provisions are inserted for further definition,
limitation and regulation of the powers of the Corporation and of its directors
and stock holders:

            (1) The By-Laws of the Corporation may be altered, amended or
         repealed and new By-Laws may be adopted (i) by the affirmative vote of
         the shares representing a majority of the votes entitled to be cast by
         the Voting Stock; provided, however, that any proposed alteration,
         amendment or repeal of, or the adoption of any By-Law inconsistent
         with, Sections 3, 7, 10 or 11 of Article II of the By-Laws or Sections
         1, 2 or 11 of Article III (in each case, as in effect on the date
         hereof) of the By-Laws or this sentence, by the stockholders shall
         require the affirmative vote of shares representing (x) not less than
         662/3% (or, from and after the Second Trigger Date, 80%) of the votes
         entitled to be cast by the Voting Stock and (y) in addition, from and
         after the First Trigger Date (if there are any shares of Class B Common
         Stock outstanding), a majority of the votes entitled to be cast by the
         holders of each class of Common Stock, voting separately by class; and
         provided, further, however, that in the case of any such stockholder
         action at a special meeting of stockholders, notice of the proposed
         alteration, amendment, repeal or adoption of the new By-Law or By-Laws
         must be contained in the notice of such special meeting, or (ii) by
         action of the Board of Directors of the Corporation.

            (2) No director shall be personally liable to the Corporation or 
         any of its stockholders for monetary damages for breach of fiduciary
         duty as a director, except for liability 



                                       17
<PAGE>   18
         (i) for any breach of the director's duty of loyalty to the Corporation
         or its stockholders, (ii) for acts or omissions not in good faith or
         which involve intentional misconduct or a knowing violation of law,
         (iii) pursuant to Section 174 of the GCL or (iv) for any transaction
         from which the director derived an improper personal benefit. Any
         repeal or modification of this Article FIFTH by the stockholders of the
         Corporation shall not adversely affect any right or protection of a
         director of the Corporation existing at the time of such repeal or
         modification with respect to acts or omissions occur ring prior to
         such repeal or modification.

            (3) In addition to the powers and authority hereinbefore or by
         statute expressly conferred upon them, the directors are hereby
         empowered to exercise all such powers and do all such acts and things
         as may be exercised or done by the Corporation, subject, nevertheless,
         to the provisions of the GCL, this Certificate of Incorporation, and
         any By-Laws adopted by the stockholders; provided, however, that no
         By-Laws hereafter adopted by the stockholders shall invalidate any
         prior act of the directors which would have been valid if such By-Laws
         had not been adopted.

            (4) So long as DuPont beneficially owns shares representing 10% or
         more of the votes entitled to be cast by the Voting Stock, nominations
         and shareholder proposals by DuPont shall not be subject to the advance
         notice procedures (including the form, content, or timing requirements
         contained therein) of Sections 10 and 11 of Article II of the By-Laws.

                  SIXTH: A. In anticipation that (i) the Corporation will cease
to be a wholly owned subsidiary of the DuPont Company, but that DuPont will
remain a stock holder of the Corporation and have continued contractual,
corporate and business relations with the Corporation, and in anticipation that
the Corporation and DuPont may enter into contracts or otherwise transact
business with each other and that the Corporation may derive benefits therefrom
and (ii) the Corporation may from time to time enter into contractual, corporate
or business relations with one or more of its directors, or one or more
corporations, partnerships, associations or other organizations in which one or
more of its directors have a financial interest (collectively, "Related
Entities"), the provisions of this Article SIXTH are set forth to regulate and
define certain contractual relations of the Corporation as they may involve
DuPont, Related Entities and their respective officers and directors, and the



                                       18
<PAGE>   19

powers, rights, duties and liabilities of the Corporation and its officers,
directors and stockholders in connection therewith. The provisions of this
Article SIXTH are in addition to, and not in limitation of, the provisions of
the GCL and the other provisions of this Certificate of Incorporation. Any
contract or business relation which does not comply with the procedures set
forth in this Article SIXTH shall not by reason thereof be deemed void or
voidable or result in any breach of fiduciary duty or duty of loyalty or failure
to act in good faith or in the best interests of the Corporation or derivation
of any improper personal benefit, but shall be governed by the provisions of
this Certificate of Incorporation, the By-Laws, the GCL and other applicable
law.

         B. No contract, agreement, arrangement or transaction (or any
amendment, modification or termination thereof) between the Corporation and
DuPont or between the Corporation and one or more of the directors or officers
of the Corporation, DuPont or any Related Entity or between the Corporation and
any Related Entity shall be void or voidable solely for the reason that DuPont,
any Related Entity or any one or more of the officers or directors of the
Corporation, DuPont or any Related Entity are parties thereto, or solely because
any such directors or officers are present at or participate in the meeting of
the Board of Directors or committee thereof which authorizes the contract,
agreement, arrangement or transaction (or the amendment, modification or
termination thereof), or solely because his or their votes are counted for such
purpose, and DuPont, any Related Entity and such directors and officers (a)
shall have fully satisfied and fulfilled their fiduciary duties to the
Corporation and its stockholders with respect thereto, (b) shall not be liable
to the Corporation or its stockholders for any breach of fiduciary duty by
reason of the entering into, performance or consummation of any such contract,
agreement, arrangement or transaction (or amendment, modification or
termination thereof), (c) shall be deemed to have acted in good faith and in a
manner such persons reasonably believe to be in and not opposed to the best
interests of the Corporation and (d) shall be deemed not to have breached their
duties of loyalty to the Corporation and its stockholders and not to have
derived in improper personal benefit therefrom, if:



                                       19
<PAGE>   20

                                    (i) the material facts as to the contract, 
                           agreement, arrangement, transaction, amendment,
                           modification or termination are disclosed or are
                           known to the Board of Directors or the committee
                           thereof which authorizes the contract, agreement, 
                           arrangement or transaction (or the amendment,
                           modification or termination thereof), and the Board
                           of Directors or such committee in good faith
                           authorizes the contract, agreement, arrangement or
                           transaction (or the amendment, modification or
                           termination thereof) by the affirmative vote of a
                           majority of the disinterested directors, even though
                           the disinterested directors be less than a quorum;

                                    (ii) the material facts as to the contract,
                           agreement, arrangement or transaction (or the
                           amendment, modification or termination thereof) are
                           disclosed or are known to the holders of Voting Stock
                           entitled to vote thereon, and the contract,
                           agreement, arrangement, or transaction (or the
                           amendment, modification or termination thereof) is
                           specifically approved in good faith by vote of the
                           holders of a majority of the then outstanding Voting
                           Stock not owned by the DuPont Company or a Related
                           Entity, as the case may be; or

                                    (iii) such contract, agreement, arrangement
                           or transaction (or the amendment, modification or
                           termination thereof) is fair as to the Corporation
                           as of the time it is authorized, approved or
                           ratified by the Board of Directors, a committee
                           thereof or the stockholders of the Corporation.




                                       20
<PAGE>   21

         C. Directors of the Corporation who are also directors or officers of 
DuPont or any Related Entity may be counted in determining the presence of a
quorum at a meeting of the Board of Directors or of a committee which authorizes
the contract, agreement, arrangement or transaction (or the amendment,
modification or termination thereof). Voting Stock owned by DuPont and any
Related Entities may be counted in determining the presence of a quorum at a
meeting of stockholders which authorizes the contract, agreement, arrangement or
transaction.

         D. Any person or entity purchasing or otherwise acquiring any interest
in any shares of capital stock of the Corporation will be deemed to have notice
of and to have consented to the provisions of this Article SIXTH.

         E. For purposes of this Article SIXTH, any contract, agreement,
arrangement or transaction (or amendment, modification or termination thereof)
with any corporation, partnership, joint venture, association or other entity in
which the Corporation owns (directly or indirectly) 50% or more of the
outstanding voting stock, voting power, partnership interests or similar
ownership interests, or with any officer or director thereof, shall be deemed to
be a contract, agreement, arrangement or transaction with the Corporation.

            SEVENTH: Meetings of stockholders may be held within or without the 
State of Delaware, as the By-Laws may provide. The books of the Corporation may
be kept (subject to any provision contained in the GCL) outside the State of
Delaware at such place or places as may be designated from time to time by the
Board of Directors or in the By-Laws of the Corporation.

            EIGHTH: Any action required or permitted to be taken by the
stockholders of the Corporation may be effected by a consent in writing by such
holders in accordance with Section 228 of the GCL; provided, however, that on
and after the Second Trigger Date, any action required or permitted to be taken
by the stockholders of the Corporation may be effected only at a duly called
annual or special meeting of such holders and may not be effected by a consent
in writing by such holders in lieu of such a meeting. Effective on and after the
Second Trigger Date, except as otherwise required by law, special meetings of
stockholders of the Corporation for 



                                       21
<PAGE>   22


any purpose or purposes may be called only by the Board of Directors pursuant to
a resolution stating the purpose or purposes thereof or by the Chairman of the
Board of Directors of the Corporation and, effective on and after the Second
Trigger Date, any power of stockholders to call a special meeting is
specifically denied. No business other than that stated in the notice of such
meeting shall be transacted at any special meeting.

             NINTH: A. In addition to any affirmative vote that may be  required
     by law, this Certificate of Incorporation or the By-Laws of the
     Corporation, and except as otherwise expressly provided in paragraph (B) of
     this Article NINTH:

         (i) any merger or consolidation of the Corporation or any subsidiary of
the Corporation with or into (A) any Related Person or (B) any Person that is an
Affiliate of a Related Person; or

         (ii) any sale, lease, exchange, transfer or other disposition by the
Corporation to any Related Person or any Affiliate of any Related Person of all
or substantially all of the assets of the Corporation; or

         (iii) any reclassification of securities (including any reverse stock
split) or recapitalization of the Corporation for which the approval of
shareholders of the Corporation is otherwise required, or any merger,
consolidation or share exchange of the Corporation with any of its subsidiaries
for which the approval of shareholders of the Corporation is otherwise
required, which has the effect, either directly or indirectly, of increasing by
more than 1% the proportionate share of the Class A Common Stock, Class B Common
Stock or Voting Stock Beneficially Owned by any Related Person or any Affiliate
of any Related Person; or

         (iv) any dissolution of the Corporation voluntarily caused or proposed 
     by or on behalf of a Related Person or any Affiliate of any Related Person,

shall require the affirmative vote of shares representing (x) not less than 80%
of the  votes entitled to be cast by the Voting Stock, (y) not less than
66 2/3% of the Voting Stock not Beneficially Owned, directly or indirectly, by
any Related Person and (z) in addition, from and 


                                       22
<PAGE>   23
after the First Trigger Date, a majority of the votes entitled to be cast by
the holders of each class of Common Stock (excluding all shares Beneficially
Owned, directly or indirectly, by any Related Person), voting separately as a
class, with respect to such Business Combination; provided that, at any time
prior to the Second Trigger Date, the required percentage in clause (x) shall be
66 2/3% and the required percentage in clause (y) shall be 50.01%. Such
affirmative vote shall be required, notwithstanding the fact that no vote may be
required, or that a lesser percentage may be specified, by law, else where in
this Certificate of Incorporation, in the By-laws of the Corporation or in any
agreement with any national securities exchange or otherwise. Notwithstanding
anything to the contrary set forth herein, the provisions of this Article NINTH
shall not be applicable at such time as all shares of Class B Common Stock have
been converted into, or exchanged for, Class A Common Stock.

         B. The provisions of paragraph (A) shall not be applicable to any
particular Business Combination, and such Business Combination shall require
only such affirmative vote as is required by law, the By-Laws of the Corporation
and any other provision of the Certificate of Incorporation, if all of the
conditions specified in either of the following paragraphs (B)(i) and (B)(ii)
are met:

         (i) the cash, property, securities or other consideration to be
received per share by holders of the Class A Common Stock and Class B Common
Stock in the Business Combination is the same with respect to both classes and
is either (A) the same in form and amount per share as the highest consideration
paid by the Related Person in a tender or exchange offer in which such Related
Person acquired at least 50% of the outstanding stock of either the Class A
Common Stock or the Class B Common Stock and which was consummated not more than
one year prior to the date of such Business Combination, or if earlier, the
entering into of a definitive agreement providing therefor or (B) not less in
amount (as to cash) or Fair Market Value (as to consideration other than cash)
as of the date of the determination of the Highest Per Share Price (as to
property, securities or other consideration) than the Highest Per Share Price;
provided that, in the event of any Business Combination 



                                       23
<PAGE>   24


in which the Corporation survives, any shares retained by the holders thereof
shall constitute consideration other than cash for purposes of this paragraph
(B)(i); or

         (ii) a majority of the Continuing Directors shall have expressly
approved such Business Combination either in advance of or subsequent to such
Related Person's having become a Related Person.

         In the case of any Business Combination with a Related Person to which
paragraph (B)(ii) above does not apply, a majority of the Continuing Directors,
promptly following the request of a Related Person, shall determine the Highest
Per Share Price for each class or series of stock of the Corporation. Such
determination shall be announced not less than five days prior to the meeting at
which holders of shares vote on the Business Combination. Such determination
shall be final, unless the Related Person becomes the Beneficial Owner of
additional shares of Common Stock after the date of the earlier determination,
in which case the Continuing Directors shall make a new determination as to the
Highest Per Share Price for each class or series of shares prior to the
consummation of the Business Combination.

         A Related Person shall be deemed to have acquired a share at the time
that such Related Person became the Beneficial Owner thereof. With respect to
shares owned by Affiliates, Associates and other Persons whose ownership is
attributable to a Related Person, if the price paid by such Related Person for
such shares is not determinable by a majority of the Continuing Directors, the
price so paid shall be deemed to be the higher of (i) the price paid upon the
acquisition thereof by the Affiliate, Associate or other Person or (ii) the
Share Price of the shares in question at the time when the Related Person became
the Beneficial Owner thereof.

         C. For purposes of this Article NINTH and notwithstanding anything to
the contrary set forth in this Certificate of Incorporation:

         (i) The term "Affiliate," used to indicate a relationship to a
specified Person, shall mean a Person that directly, or indirectly through one
or more intermediaries, controls, is controlled by, or is under common control
with, such specified Person.




                                       24
<PAGE>   25



         (ii) The term "Associate," used to indicate a relationship with a
specified Person, shall mean (A) any corporation, partnership, limited liability
company, association, joint venture or other organization (other than the
Corporation or any wholly owned subsidiary of the Corporation) of which such
specified Person is an officer or partner or is, directly or indirectly, the
Beneficial Owner of 10% or more of any class of equity securities; (B) any trust
or other estate in which such specified Person has a beneficial interest of 10%
or more or as to which such specified Person serves as trustee or in a similar
fiduciary capacity; (C) any Person who is a director or officer of such
specified Person or any of its parents or subsidiaries (other than the
Corporation or any wholly owned subsidiary of the Corporation); and (D) any
relative or spouse of such specified Person or of any of its Associates, or any
relative of any such spouse, who has the same home as such specified Person or
such Associate.

         (iii) A Person shall be a "Beneficial Owner" of any stock (A) which
such Person or any of its Affiliates or Associates beneficially owns, directly
or indirectly; or (B) which such Person or any of its Affiliates or Associates
has, directly or indirectly, (1) the right to acquire (whether such right is
exercisable immediately or only after the passage of time), pursuant to any
agreement, arrangement or understanding or upon the exercise of conversion
rights, exchange rights, warrants or options, or otherwise, or (2) the right to
vote pursuant to any agreement, arrangement or understanding; or (C) which is
beneficially owned, directly or indirectly, by any other Person, with which such
Person or any of its Affiliates or Associates has any agreement, arrangement or
understanding for the purpose of acquiring, holding, voting or disposing of such
stock; or (D) of which such Person would be the Beneficial Owner pursuant to the
terms of Rule 13d-3 of the Exchange Act, as in effect on September 30, 1998.
Stock shall be deemed "Beneficially Owned" by the Beneficial Owner or Owners
thereof.

         (iv) The term "Business Combination" shall mean any transaction which
is referred to in any one or more of clauses (i) through (iv) of paragraph (A)
of this Article NINTH.




                                       25
<PAGE>   26



         (v) The term "Continuing Director" shall mean, with respect to a
Business Combination with a Related Person, any director of the Corporation who
is unaffiliated with the Related Person and was a director prior to the time
that the Related Person became a Related Person, and any successor of a
Continuing Director who is unaffiliated with the Related Person and is
recommended or nominated to succeed a Continuing Director by a majority of the
Continuing Directors. Without limiting the generality of the foregoing, a
director shall be deemed to be affiliated with a Related Person if such
director (A) is an officer, director, employee or general partner of such
Related Person; (B) is an Affiliate or Associate of such Related Person; (C) is
a relative or spouse of such Related Person or of any such officer, director,
general partner, Affiliate or Associate; (D) performs services, or is a member,
employee, greater than 5% stockholder or other equity owner of any organization
(other than the Corporation and its subsidiaries) which performs services for
such Related Person or any Affiliate of such Related Person, or is a relative or
spouse of any such Person; or (E) was nominated for election as a director by
such Related Person. Notwithstanding anything to the contrary set forth herein,
any person nominated with the approval of the DuPont Company shall be deemed to
be a Continuing Director.

         (vi) The term "Fair Market Value" shall mean, in the case of
securities, the average of the closing sales prices during the 30-day period
immediately preceding the date in question of such security on the principal
United States securities exchange registered under the Exchange Act on which
such security is listed (or the composite tape therefor) or, if such securities
are not listed on any such exchange, the average of the last reported sales
price (if so reported) or the closing bid quotations with respect to such
security during the 30-day period preceding the date in question on the New
York Stock Exchange or, if no such quotations are available, the fair market
value on the date in question of such security as determined in good faith by a
majority of the Continuing Directors; and in the case of property other than
cash or securities, the fair market value of such property on the date in
question as determined in good faith by a majority of the Continuing Directors.




                                       26
<PAGE>   27

         (vii) The term "Highest Per Share Price" shall mean, with respect to a
Related Person, the highest price that can be determined to have been paid or
agreed to be paid for any share or shares of the Class A Common Stock, Class B
Common Stock, or Voting Stock by such Related Person in a transaction that
either (1) resulted in such Related Person's Beneficially Owning 15% or more of
the Class A Common Stock, Class B Common Stock, or Voting Stock outstanding or
(2) was effected at a time when such Related Person Beneficially Owned 15% or
more of the Class A Common Stock, Class B Common Stock, or Voting Stock
outstanding, in either case occurring not more than one year prior to the date
of the Business Combination. In determining the Highest Per Share Price,
appropriate adjustment will be made to take into account (w) distributions paid
or payable in stock, (x) subdivisions of outstanding stock, (y) combinations of
shares of stock into a smaller number of shares and (z) similar events.

         (viii) The term "Person" shall mean any individual, corporation,
limited liability company, association, partnership, joint venture, trust,
estate or other entity or organization.

         (ix) The term "Related Person" shall mean any Person (other than the
Corporation or any subsidiary of the Corporation and other than any profit
sharing, employee ownership or other employee benefit plan of the Corporation
or any subsidiary of the corporation or any trustee of or fiduciary with respect
to any such plan when acting in such capacity) who or which (A) is the
Beneficial Owner of 15% or more of the Class A Common Stock, Class B Common
Stock or Voting Stock outstanding; or (B) is an Affiliate of the Corporation and
at any time within the two-year period immediately prior to the date in question
was the Beneficial Owner of 15% or more of the Class A Common Stock, Class B
Common Stock or Voting Stock outstanding. For the purposes of determining
whether a Person is a Related Person, the number of shares of any class or
series deemed to be outstanding shall include shares of such class or series of
which the Person is deemed the Beneficial Owner, but shall not include any other
shares which may be issuable pursuant to any agreement, arrangement or
understanding, or upon exercise of conversion rights, warrants or options,
otherwise. Notwithstanding anything to the contrary herein, neither DuPont nor
its Affiliates or Associates shall be deemed to be Related Persons.



                                       27
<PAGE>   28



         D. Nothing contained in this Article NINTH shall be construed to
relieve any Related Person from any fiduciary obligation imposed by law.

         E. Notwithstanding any other provision of this Certificate of
Incorporation (and notwithstanding that a lesser percentage may be specified by
law), the affirmative vote of shares representing (x) not less than 80% of the 
votes entitled to be cast by the Voting Stock, (y) not less than 66 2/3% of the
Voting Stock not Beneficially Owned, directly or indirectly, by any Related
Person and (z) in addition, from and after the First Trigger Date, a majority of
the votes entitled to be cast by the holders of each class of Common Stock
(excluding all shares Beneficially Owned, directly or indirectly, by any Related
Person), voting separately by class, shall be required to amend or re peal, or
adopt any provisions inconsistent with, this Article NINTH; provided that, at
any time prior to the Second Trigger Date, the required percentage in clause (x)
shall be 66 2/3% and the required percentage in clause (y) shall be 50.01%.




                                       28
<PAGE>   29


         IN WITNESS WHEREOF, this Second Amended and Restated Certificate of 
Incorporation which restates, integrates and amends the provisions of the
Amended and Restated Certificate of Incorporation of the Corporation, and which
has been duly adopted in accordance with Sections 242 and 245 of the Delaware
General Corporation Law, has been executed by an authorized officer of the
Corporation this 20th day of October, 1998.

                                          Conoco Inc.



                                          By: /s/ R. A. HARRINGTON
                                              ----------------------------------
                                               Name:  R. A. Harrington
                                               Title: Senior Vice President,
                                                      Legal and General Counsel