<PAGE>
                                                        Exhibit 4.06

  PROTOCOL AND JUSTIFICATION OF THE OPERATION OF INCORPORATION OF NITROCARBONO
                              S.A. BY BRASKEM S.A.

                               Made by and between

BRASKEM  S.A.,  a company  with  headquarters  at Rua Eteno n.o  1.561,  city of
Camacari,  state of Bahia,  enrolled at the CNPJ/MF under #  42.150.391/0001-70,
herein represented  according to its By-laws,  hereinafter simply referred to as
"INCORPORATOR";

                                       and

NITROCARBONO S.A., a company with headquarters at Rua Hidrogenio n.o 2.318, city
of Camacari, state of Bahia, enrolled at the CNPJ/MF under # 13.558.218/0001-08,
herein represented  according to its By-laws,  hereinafter simply referred to as
"INCORPORATED";

INCORPORATOR and INCORPORATED are jointly referred to as "PARTIES",

with the  purpose  of  promoting  the  incorporation  into an  already  existing
company,  according to articles  224, 225 and 264 of Law # 6.404 dated  December
15, 1976.

                                    Whereas:

(i)       The INCORPORATOR holds 49.957.106 common shares and 87.906.743 class A
          preferred  shares and 1.576  class B  preferred  shares  issued by the
          INCORPORATED,  which shares  represent  100% of the corporate  capital
          entitled to vote and 93,83% of the total capital of the INCORPORATED;

(ii)      the operation of incorporation of the INCORPORATED by the INCORPORATOR
          will  represent  gains of  synergies  to the  PARTIES,  result  in the
          simplification   of  the  current   structure  by  consolidating   the
          activities  of  the  PARTIES  in a  single  company,  with  consequent
          reduction of  financial,  operational  costs,  rationalization  of the
          activities of the PARTIES; and

(iii)     the reports on (a) accounting evaluation of the equity of the PARTIES,
          and (b) evaluation,  at market prices, of the equities of the PARTIES,
          prepared and delivered by the  specialized  company,  are according to
          the  applicable   laws  and   regulations  and  to  the  operation  of
          incorporation this Protocol and Justification is about.

The Board of Directors of the PARTIES,  in the best form of law, hereby proposes
the  incorporation  of the  INCORPORATED  by the  INCORPORATOR  by signing  this
Protocol and Justification of the incorporation  ("Protocol and  Justification")
whit the purpose of establishing,  according to articles 224, 225 and 264 of Law
# 6.404 dated December 15, 1976, as well as Instruction CVM # 319 dated December
3, 1999, and subject to the provisions of items 9.1 and 9.2, the following terms
and conditions related to said operation of incorporation.
<PAGE>

                             1. INCORPORATION BASES

1.1 The INCORPORATOR  will perform the incorporation of the INCORPORATED and the
equity of the latter  will be  transferred  to the  equity of the  INCORPORATOR,
which will succeed it according to law (universal descent) ("Incorporation").

1.2 The evaluations of the equities of the  INCORPORATED and  INCORPORATOR,  for
the  purposes  of the  respective  accounting  entries  into  the  INCORPORATOR,
determination  of ratio of  substitution of the shares of the  INCORPORATED  for
shares of the  INCORPORATOR and calculation of the value of reimbursement of the
shares issued by the INCORPORATED,  in case of eventual exercise of the right of
withdrawal the  shareholders of the  INCORPORATED  are entitled to, were carried
out at book  value by the  specialized  company  mentioned  in item 2.1,  on the
reference date established in item 2.2, based on the criteria  foreseen in Law #
6.404 dated  December 15, 1976 and according to the criteria  established in the
instruction CVM # 319/99 for the elaboration of financial statements.

1.3 The  balances  of credit  and debit  accounts  of the  INCORPORATED  will be
transferred to the accounting books of the INCORPORATOR, paying attention to the
proper adaptations.

1.4 The assets, rights and obligations of the INCORPORATED comprising the equity
to be  transferred  to the  INCORPORATOR  are those  described in details in the
evaluation report, at book value.

1.5 The  INCORPORATOR's  management  will be in  charge of  practicing  all acts
necessary to implement the Incorporation, and all the costs and expenses related
to said implementation will run on its account.

1.6 The INCORPORATED will be dissolved in full right.

             2. EVALUATIONS AND REFERENCE DATE OF THE INCORPORATION

2.1   The   indication   and    appointment   of   the    specialized    company
PricewaterhouseCoopers   Auditores   Independentes,   a   civil   company   with
headquarters  in the city of Sao Paulo at Av.  Francisco  Matarazzo,  n.o 1.700,
from the 7th to the 11th  floors  and  from the 13th to the 20th  floors,  Torre
Torino,  with branch in the city of Salvador at Rua Miguel  Calmon,  n.o 555, 9o
andar,  secondarily registered at the Regional Board of Accountancy of the State
of Bahia under # CRC  2SP000160/O-5 "S" BA and enrolled at the Tax Roll of Legal
Entities of the Treasury Department under # 61.562.112/0004-73, with articles of
Incorporation  filed at the 4th  Registry  of  Documents  of Sao  Paulo,  SP, on
September  17, 1956,  and further  amendments  registered at the 2nd Registry of
Documents  of Sao Paulo,  SP, the last of them being filed  (microfilm)  under #
68.444 on April 15,  2002,  represented  by its partner,  Mr.  Marco  Aurelio de
Castro  e Melo,  as the  person  in  charge  of  preparing  (i)  the  accounting
evaluation  reports regarding the equities of the INCORPORATED and INCORPORATOR,
for the  purposes  of  accounting  entries  of the  INCORPORATOR,  in  order  to
determine the ratio of  substitution  of the shares,  as well as to the eventual
exercise of the right of withdrawal ("Accounting Evaluation Reports"),  and (ii)
the  evaluation  reports of the equities of the  PARTIES,  according to the same
criteria,  at market prices and on the same Reference Date of the  Incorporation
("Reports  on  Evaluation  at Market  Prices"),  under the terms of art. 264 and
respective ss.s of Law # 6.404, shall be ratified by the Special General Meeting
of the  INCORPORATOR and  INCORPORATED,  under the terms and for the purposes of
article 227, ss. 1st of Law # 6.404 dated December 15, 1976.

2.2  PricewaterhouseCoopers  Auditores Independentes is a company specialized in
evaluating  companies of the size of the INCORPORATED  and INCORPORATOR  and, at
the PARTIES'  management  request, it
<PAGE>

has proceeded to (i) evaluate the equities of the  INCORPORATED and INCORPORATOR
at the book value,  based on the elements appearing on the Balance Sheets of the
PARTIES prepared on December 31, 2002 ("Reference Date of Incorporation"),  (ii)
evaluate the equities of the PARTIES  according to the same criteria,  at market
prices and on the same Reference Date, (iii) elaborate the Accounting Evaluation
Reports,  which  are  the  Exhibits  A and  B  attached  to  this  Protocol  and
Justification, the values being subject to previous analysis and approval of the
shareholders of the PARTIES, according to the law, (iv) elaborate the Reports on
Evaluation  at Market  Prices,  which are the  Exhibits C and D attached to this
Protocol and  Justification,  the values being subject to previous  analysis and
approval of the shareholders of the PARTIES, according to the law.

                 3. FULL AMOUNT OF THE EQUITY TO BE INCORPORATED

3.1 According to the accounting  evaluation of the INCORPORATED,  the book value
of the equity of the INCORPORATED to be transferred to the INCORPORATOR is of R$
604.288,85, provided the provisions of Clause 4 below are observed.

         4. TREATMENT OF EQUITY VARIATIONS UNTIL THE INCORPORATION DATE

4.1 The equity variations  verified from the Reference Date of the Incorporation
will be apportioned  by the  INCORPORATOR,  being  transferred to its accounting
books, and the necessary changes will be made, irrespective of the fact that the
INCORPORATOR  may  continue,  provisionally,  to conduct the  operations  on its
behalf  until the  formalization  of all the  records and  obtaining  of all the
authorizations demanded by the applicable legislation.

                     5. RATIO OF SUBSTITUTION OF THE SHARES
                        FOR THE PURPOSES OF INCORPORATION

5.1 As a result of the incorporation,  the shareholders of the INCORPORATED will
receive,  in substitution for their shares representing the corporate capital of
the INCORPORATED, shares issued by the INCORPORATOR,  according to the following
ratio of substitution  established based on the book values of the shares of the
PARTIES  verified  as  provided  for in the  above  item 2.1,  appearing  on the
Accounting Evaluation Reports.

<TABLE>
<CAPTION>
-------------------------------------------------------------------------------------------------------------------
Company              Current         Book value of     Book value    Book         Ratio of   Ratio of    "Standard"
                     number of       the company (in   (in R$) per   value        exchange   exchange    lot of
                     shares issued   R$)               "standard"    (in R$)      common     preferred   shares
                                                       lot of        per          shares     shares
                                                       preferred     "standard"
                                                       shares (++)   lot of
                                                                     common
                                                                     shares
-------------------------------------------------------------------------------------------------------------------
<S>                  <C>             <C>                    <C>          <C>         <C>         <C>          <C>
INCORPORATOR (+)     3.398.313.224   1.871.636.903,02       550,75       550,75          -           -        1.000
-------------------------------------------------------------------------------------------------------------------
INCORPORATED           146.932.713         604.288,86         4,11         4,11      0,007       0,007        1.000
-------------------------------------------------------------------------------------------------------------------
</TABLE>
(+) Amount of shares of the INCORPORATOR,  not considering the 53.007.864 shares
on treasury.
(++) Book value per "standard" lot of preferred  shares,  irrespective  of their
class.
<PAGE>

 6. VERIFICATION OF THE RATIO OF SUBSTITUTION OF THE SHARES FOR THE PURPOSES OF
                           ART. 264 OF LAW # 6.404/76

6.1 In compliance with the provisions of said article 264 of Law # 6.404/76, the
table below shows the  theoretical  ration of  substitution of common shares and
class A preferred shares issued by the INCORPORATED  for,  respectively,  common
shares and class A  preferred  shares  issued by the  INCORPORATOR,  established
based on the values of the equities of the PARTIES,  evaluated  according to the
same criteria, at market prices, on the Reference Date of the Incorporation,  as
appearing on the Reports on Evaluation  at Market  Prices,  exclusively  for the
purposes of the comparison foreseen in said article of Law # 6.404/76.

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------------------------------
Company              Current         Book value of      Book value    Book         Ratio of   Ratio of    "Standard"
                     number of       the company (in    (in R$) per   value        exchange   exchange    lot of
                     shares issued   R$)                "standard"    (in R$)      common     preferred   shares
                                                        lot of        per          shares     shares
                                                        preferred     "standard"
                                                        shares (++)   lot of
                                                                      common
                                                                      shares
--------------------------------------------------------------------------------------------------------------------
<S>                  <C>             <C>                   <C>          <C>           <C>         <C>          <C>
INCORPORATOR (+)     3.398.313.224   4.647.165.000,00      1.367,49     1.367,49          -           -        1.000
--------------------------------------------------------------------------------------------------------------------
INCORPORATED           146.932.713      75.891.375,74        516,50       516,50      0,378       0,378        1.000
--------------------------------------------------------------------------------------------------------------------
</TABLE>
(+) Amount of shares of the INCORPORATOR,  not considering the 53.007.864 shares
on treasury.
(++) Book value per "standard" lot of preferred  shares,  irrespective  of their
class.

                             7. REIMBURSEMENT VALUE

7.1  The  reimbursement   value  of  the  shares  of  the  shareholders  of  the
INCORPORATED  dissenting  from  the  Incorporation  was  defined  based  on  the
evaluation of the accounting equity of the INCORPORATED, under the terms of art.
45 of Law # 6.404/76, and is as follows:

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------------------------------------
Book value of the INCORPORATED (in   Book value per lot of 1.000         Book value per lot of 1.000
R$)                                  common shares for the purposes of   preferred shares for the purposes
                                     reimbursement (in R$):              of reimbursement (in R$)(+):
-----------------------------------------------------------------------------------------------------------
<S>                     <C>                                       <C>                                 <C>
                        604.288,86                                4,11                                4,11
-----------------------------------------------------------------------------------------------------------
</TABLE>
(++) Book value per "standard" lot of preferred  shares,  irrespective  of their
class.

7.2 Under the terms of the  provisions  of art.  264, ss. 3rd of Law # 6.404/76,
the dissenting shareholders of the INCORPORATED wishing to exercise the right of
withdrawal  because of the  Incorporation  may  choose to  receive  the price of
reimbursement  of their shares based on (i) their book value  established in the
above item 7.1, under the terms of art. 45 of Law # 6.404/76;  or (ii) the value
of the equity of the INCORPORATED evaluated at market prices established in item
6.1 of this Protocol and Justification.

                       8. INCORPORATOR'S CAPITAL INCREASE

8.1 Based on the Accounting Evaluation Report mentioned in item 2.1 and in order
to support the issue of shares of the INCORPORATOR, the corporate capital of the
INCORPORATOR   will  be  increased  in  R$  37.284,62,   not   considering   the
INCORPORATOR's interest in the INCORPORATED's corporate capital.

8.2 The  INCORPORATOR's  corporate capital increase will be realized by means of
the  issue of 68 new  shares,  being 2 common  shares  and 66 class A  preferred
shares, all of them with the same rights and advantages  attributed according to
the by-laws of the  INCORPORATOR,  to be attributed to the  shareholders  of the
INCORPORATED,  in substitution  for the shares issued by the  INCORPORATED  that
will be extinct,  as per the ratio of  substitution  established  in item 5.1 of
this Protocol and  Justification,  and the shares issued  according to this item
will participate fully in the results of this corporate year.
<PAGE>

8.3 The  Incorporation  of the  INCORPORATED  shall  occur at the  same  General
Meeting that will approve the incorporation,  by the INCORPORATOR,  of ECONOMICO
S.A.  EMPREENDIMENTOS  (ESAE) and of OPP  QUIMICA  S.A..  In this  context,  the
corporate  capital  of  the   INCORPORATOR,   by  the  end  of  the  process  of
incorporation of those companies, is estimated to be R$ 1.871.713.164,92 divided
into  1.226.091.150  common shares and  2.172.222.142  preferred  shares,  being
2.160.764.402  class A preferred shares and 11.457.740 class B preferred shares,
and  Article  4th of the  by-laws  of the  INCORPORATOR  will  read as  follows:
"Article  4th - The  Corporate  Capital is of R$  1.871.713.164,92  divided into
3.398.313.292  shares, being 1.226.091.150 common shares,  2.160.764.402 class A
preferred shares and 11.457.740 class B preferred shares.

8.4 The shares issued by the  INCORPORATOR to be attributed to the  shareholders
of the  INCORPORATED  in  substitution  for the shares that will be extinct will
deserve  the same  rights  of the  shares  issued  by the  INCORPORATOR,  as now
outstanding.  The  preferences  and  advantages of the class A preferred  shares
issued by the INCORPORATOR, as established in article 9th of its by-laws, are as
follows:

a)   class A  preferred  shares,  as well as class B preferred  shares,  are not
     entitled  to vote,  however,  they  entitle  their  holders to  priority in
     receiving  a minimum,  non-cumulative  dividend of 6% (six per cent) on its
     unitary  value,  according to the profits  available  for  distribution  to
     shareholders.  Unitary  value of shares means the division of the corporate
     capital by the total outstanding shares;

b)   since the dividend  mentioned in the above line "a" is paid for the class A
     and class B  preferred  shares,  and for the  common  shares  issued by the
     INCORPORATOR,  the  class A  preferred  shares  will  compete,  on the same
     conditions,  with the common  shares in the  distribution  of the remaining
     profit;

c)   the class A preferred  shares and the common shares will participate in the
     distribution,  by the INCORPORATOR,  of shares resulting from incorporation
     of reserves to the corporate capital;

d)   the  class A and class B  preferred  shares  are  assured  priority  in the
     reimbursement of capital; and

e)   all the classes and types of shares issued by the INCORPORATOR will deserve
     the rights of joint sale ("tag along") in case of alienation of the control
     of the INCORPORATOR,  at the same price per share paid to the alienator(s).
     The right of joint sale shall not apply if the  transfer  of the control of
     the  INCORPORATOR  occurs:  (a) in view of a decision  or legal act such as
     pledge or adjudication in execution or (b) in view of the final decision of
     the regulatory boards,  including the Administrative  Committee of Economic
     Defense - CADE.

8.5 The shares of the INCORPORATED's  capital belonging to the INCORPORATOR will
be extinct based on art. 226, ss. 1st of Law # 6.404 dated December 15, 1976.

                              9. SPECIAL CONDITIONS

9.1 The operation of Incorporation  proposed in this Protocol and  Justification
will  be  informed  to  the  Auditing   Committees  of  the   INCORPORATED   and
INCORPORATOR,  Managing Board of the PARTIES,  and submitted to the shareholders
of the  PARTIES  at  General  Meetings,  provided  the legal  terms for call are
observed.
<PAGE>

9.2 If the  managing  boards  understand  that the  payment  of the value of the
reimbursement  of the shares to the dissenting  shareholders of the INCORPORATED
exercising  the right of  withdrawal  will risk the  financial  stability of the
INCORPORATOR, General Meetings of the Shareholders of the PARTIES will be called
immediately,  according to the legal terms, in order to analyze the now proposed
operation and, is applicable, revert the whole incorporation process.

                                 10. CONCLUSION

10.1 Messrs.  Shareholders of the INCORPORATED and  INCORPORATOR,  these are the
norms and procedures that,  according to the law, we have formulated in order to
rule this operation of  incorporation,  which the respective Boards of Directors
consider as being of corporate interest.

                            Camacari, March 10, 2003.

                                  BRASKEM S.A.

                               (signed: illegible)
                  Mauricio Roberto de Carvalho Ferro - Director

                               (signed: illegible)
                           Paul Elie Altit - Director

                                NITROCARBONO S.A.

                               (signed: illegible)
                       Roberto Brisco Paraiso Ramos - CEO

                               (signed: illegible)
                           Paul Elie Altit - Director

Annex: