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                                                                  Exhibit 10.135


                              EMPLOYMENT AGREEMENT


      This Employment Agreement is made this 1st day of July, 1996, by and
between DONLAR CORPORATION, an Illinois corporation (the "Company"), having a
principal place of business at Moffett Campus, 6502 South Archer Avenue, Bedford
Park, Illinois 60501, and LARRY KOSKAN (KOSKAN or the "Employee"). In
consideration of the compensation agreed to and the mutual covenants and
agreements set forth herein, the parties agree as follows:

      EMPLOYMENT; DURATION

      1.01 The Company agrees to employ KOSKAN as President and Chief Executive
Officer of the Company, and KOSKAN agrees to be so employed for a period of five
(5) years beginning on the 1st day of July, 1996, provided, however, that the
Employee shall have the option to renew this Agreement for an additional two (2)
years, if this Agreement has not earlier terminated, by giving notice of renewal
not more than ninety (90) days and not less than sixty (60) days prior to the
termination of the five (5) year employment period.

      DUTIES

      2.01 The duties of the Employee shall be those of a president and chief
executive officer of the Company. KOSKAN shall be given all executive powers and
authority that are reasonably required to enable him to efficiently perform his
duties. KOSKAN shall also perform such reasonable duties as shall be determined
from time to time by the Company's Board of Directors, so long as those duties
are not inconsistent with those of chief executive officer.

      2.02 The Employee shall devote his entire productive time, ability and
attention to the business of the Company during the term of this Agreement. The
Employee shall not directly or indirectly render any services of a business,
commercial or professional nature to any other person or organization, whether
for compensation or otherwise, without the prior written consent of the Company.

      COMPENSATION

      3.01 Base Salary. As compensation for his full-time employment under this
Agreement, KOSKAN shall be paid a base salary of ONE HUNDRED EIGHTY-FIVE
THOUSAND DOLLARS ($185,000.00) per year, payable semi-monthly. The Compensation
Committee of the Board of Directors of the Company shall review Employee's
performance periodically and in its sole discretion may award increases in base
salary from time to time.

      3.02 Incentive Bonus-Cash. The Compensation Committee of the Company's
Board of Directors in its sole discretion from time to time may adopt cash bonus
programs and may grant cash bonuses to Employee in any amount such Compensation
Committee in its sole discretion deems appropriate in recognition of full or
partial attainment of goals established under such programs.

      3.03 Incentive Bonus - Stock Option. In addition to the base salary and
the discretionary cash incentive bonuses set forth above, KOSKAN shall also be
eligible to receive


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as compensation for his continued employment options to purchase shares of the
Company as an incentive bonus. Any stock option bonus shall be calculated and be
a function of the Employee's level of performance in realizing certain business
goals established by the Compensation Committee of the Board of Directors from
year to year. These annual stock option incentive bonuses shall be earned by the
degree of goal achievement obtained by the Employee and the Company in the areas
of Company business specified by the Compensation Committee.

      DISABILITY

      4.01 The Company shall pay to the Employee full compensation during any
period or periods of disability not exceeding two (2) years in aggregate
duration.

      INSURANCE BENEFITS

      5.01 The Company agrees to include the Employee in the hospital, surgical
and medical benefit plan adopted by the Company from time to time. In addition,
the Company will provide the Employee with term life insurance coverage in the
face amount of $500,000.00 throughout the employment term.

      REIMBURSEMENT OF EMPLOYEE EXPENSES

      6.01 The Employee is authorized to incur reasonable business expenses for
promoting the business of the Company, including expenditures for entertainment,
food and travel. The Company will reimburse the Employee from time to time for
all business expenses provided the Employee presents to the Company (a) receipts
for the expenditures; (b) the time, place and designation of the type of
entertainment, travel or other expense; (c) the business reason for the
expenditure and the nature of the business benefit derived; and (d) such other
information or evidence as the Company may reasonably require.

      PROPRIETARY RIGHTS

      7.01 Disclosure. The Employee shall disclose promptly to the Board of
Directors of the Company any and all inventions, trade secrets, discoveries and
improvements, whether patentable or unpatentable, conceived or made by the
Employee during the period of employment and related to the present or future
business activities of the Company, and hereby assigns and agrees to assign all
his interest therein to the Company. Whenever requested to do so by the Company,
the Employee shall execute any and all applications, assignments or other
instruments which the Company shall deem necessary to apply for and obtain
Letters Patent of the United States or any foreign country or to otherwise
protect the Company's interest in such inventions, discoveries or improvements.
It is understood that the provisions of paragraph 7.01 of this Agreement do not
apply to an invention for which no equipment, supplies, facility, or trade
secret information of the Company was used and which was developed entirely on
the Employee's own time, unless (a) the invention relates to (i) the business of
the Company, or (ii) the Company's actual or demonstrably anticipated research
and development, or (b) the invention results from any work performed by the
Employee for the Company.

      7.02 Confidentiality. During his employment with the Company or at any
time thereafter, the Employee will neither disclose to others nor use for his
own benefit or for the


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benefit of others any confidential proprietary information, including trade
secrets, know-how or other secret data, or any technical, commercial or other
nature which pertains to any of the present or future business of the Company or
of any of its subsidiaries or affiliates, and which is acquired by the Employee
during the period of his employment with the Company, except to the extent that
such disclosure or use is necessary in the ordinary course of the Employee's
performance of his duties as an employee of the Company.

      7.03 Return of Materials. Upon termination of the Employee's employment
with the Company, the Employee shall deliver to the Company all drawings,
blueprints, manuals, letters, reports, notes, memoranda, notebooks, records, and
any other documents and reproductions thereof kept by the Employee or in the
possession of the Employee whether or not prepared by the Employee, which have
been used in or pertain to any activities of the Company, including but not
limited to the work done by the Employee during the course of his employment,
and which are concerned with confidential proprietary information, including
devices, machines, products, processes, methods, compositions, formulas,
customer lists, business techniques and methods, and purchasing and sales
information and operations of the Company.

      7.04 Restrictions. If the Company has trade secrets or other confidential
data of any third party under an agreement including restrictions on disclosure,
which restrictions are known to the Employee, the Employee shall not, without
the written consent of such third party and the Company, at any time infringe
such restrictions.

      7.05 Prior Skills and Knowledge. It is understood that the provisions of
paragraphs 7.01 through 7.04 of this Agreement do not, in any way, restrict the
Employee from using either the skills and knowledge which the Employee brought
with him to the Company, or the general knowledge publicly known in the
Company's industry or related industries, which the Employee acquires during his
employment with the Company.

      NON-COMPETITION

      8.01 During his employment with the Company and for a period of two (2)
years thereafter, the Employee shall not become employed by or act on behalf of
any other person, corporation or firm which is engaged in any business or
activity similar to or competitive with that of the Company, unless such
employment or activity has been approved in advance in writing by two thirds of
the Board of the Company.

      8.02 During his employment with the Company and for a period of two (2)
years thereafter, the Employee shall not acquire or retain, either directly or
indirectly, any conflicting interest in or in connection with any person,
corporation or firm with which the Company does business, or any person,
corporation or firm which seeks to do business with the Company, or any person,
corporation or firm with which the Company competes, unless prior written
authorization therefor is given by two thirds of the Board of the Company. For
purpose of this paragraph, "conflicting interest" shall mean:

      (a)   any financial interest in a person, corporation or firm;

      (b)   any interest had, directly or indirectly, in any contract or other
            business transaction to which the Company is a party, which may
            result in monetary value


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            to the Employee or, to the extent known by the Employee, to any
            member of his family;

            or

      (c)   performing work or rendering services for, or serving as a director
            or officer of or consultant to, or permitting the Employee's name to
            be used in any fashion that would tend to indicate a business
            connection with, any person, corporation or firm, outside the normal
            course of the Employee's employment with the Company.

      The Employee shall notify the Company in writing within three (3) days of
his acquisition of any conflicting interest.

      SEVERANCE BENEFITS

      9.01 Termination. If the Employee's employment terminates at any time,
then the Employee shall be entitled to receive severance benefits as follows:

            (a) Voluntary Resignation. If the Employee's employment terminates
by reason of the Employee's voluntary resignation (and is not an Involuntary
Termination), then the Employee shall not be entitled to receive severance or
other benefits except for those (if any) as may then be established under the
Company's then existing severance and benefits plans and policies at the time of
such termination.

            (b) Involuntary Termination. If the Employee's employment is
terminated as a result of Involuntary Termination, then the Employee shall be
entitled to receive severance pay in an amount equal to the Employee's Base
Compensation for the twenty-four-calendar month period immediately preceding the
Termination Date. Any severance payments to which the Employee is entitled
pursuant to this section shall be paid in a lump sum within thirty (30) days of
the Termination Date.

            (c) Disability; Death. In addition to the benefits contained in
Section 4.01 hereof, if the Company terminates the Employee's employment as a
result of the Employee's Disability, or Employee's employment is terminated due
to the death of the Employee, then such termination shall be treated as if it
were an Involuntary Termination and severance and other benefit, if any, shall
be provided in accordance with paragraph (b) above.

      9.02 Options. Upon an Involuntary Termination, the unvested portion of any
stock option held by the Employee under the Plan shall automatically be
accelerated and the Employee or the Employee's representative, as the case may
be, shall have the right to exercise all or any portion of such stock option, in
addition to any portion of the option exercisable prior to the Involuntary
Termination. Upon a voluntary termination, the vesting of any unvested portion
of any stock option held by the Employee under the Plan shall be governed by the
Plan.

      9.03  Definitions.  The following terms referred to in this Section 9
shall have the following meanings:


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            (a) Involuntary Termination. "Involuntary Termination" shall mean
(i) without the Employee's express written consent, the assignment to the
Employee or any duties or the reduction of the Employee's position or
responsibilities with the Company in effect immediately prior to such
assignment, or the removal of the Employee from such position and
responsibilities; (ii) without the Employee's express written consent, a
substantial reduction, without good business reasons, of the facilities and
perquisites (including office space and location) available to the Employee
immediately prior to such reduction; (iii) a reduction by the Company in the
Base Compensation of the Employee as in effect immediately prior to such
reduction, other than a bonus reduction resulting from application of a bonus
formula or plan on a basis that is consistent with prior practice; (iv) material
reduction by the Company in the kind or level of employee benefits to which the
Employee is entitled immediately prior to such reduction with the result that
the Employee's overall benefits package is significantly reduced (v) the
relocation of the Employee to a facility or a location more than 25 miles from
the Employee's then present location, without the Employee's express written
consent; (vi) any purported termination of the Employee by the Company; (vii)
the failure of the Company to obtain the assumption of this Agreement by any
successors contemplated in Section 12.0 below; or (viii) any purported
termination of the Employee's employment by the Company which is not effected
pursuant to a notice of termination satisfying the requirements of Section 10.02
below, and for purposes of this Agreement, no such purported termination shall
be effective unless it complies with Section 10.02 below.

            (b) Disability. "Disability" shall mean that the Employee has been
unable to perform the essential functions of his job under this Agreement after
reasonable accommodations as the result of his incapacity due to physical or
mental illness, and such inability, at least 26 weeks after its commencement, is
determined to be total and permanent by a physician selected by the Company or
its insurers and acceptable to the Employee or the Employee's legal
representative (such agreement as to acceptability not to be unreasonably
withheld). Termination resulting from Disability may only effected after at
least 30 days' written notice by the Company of its intention to terminate the
Employee's employment. In the event that the Employee resumes the performance of
the essential functions of his job hereunder before the termination of his
employment becomes effective, the notice of intent to terminate shall
automatically be deemed to have been revoked.

            (c) Termination Date. "Termination Date" shall mean (i) if this
Agreement is terminated by the Company for Disability, 30 days after notice of
termination is given to the Employee (provided that the Employee shall not have
returned to the performance of the Employee's duties on a full-time basis during
such 30-day period), (ii) if the Employee's employment is terminated by the
Company for any other reason, the date on which a notice of termination is
given, provided that if within 30 days after the Company gives the Employee
notice of termination, the Employee notifies the Company that a dispute exists
concerning the termination, the Termination Date shall be the date on which the
dispute is finally determined, either my mutual written agreement of the
parties, by final judgment, order or decree of a court of competent
jurisdiction( the time for appeal therefrom having expired and no appeal having
been perfected), or (iii) if the Agreement is terminated by the Employee, the
date on which the Employee delivers the notice of termination to the Company.


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      NOTICES

      10.01 All notices, offers and acceptances hereunder shall be in writing
and shall be deemed to be communicated when delivered in person or deposited in
the United States mail, postage prepaid, by certified or registered mail,
addressed to the party concerned at the address appearing in the stock records
of the Company or at such other or additional place as such party may designate
by notice given in accordance with the provisions hereof to the other party
hereto.

      10.02 Notice of Termination. Any termination by the Company or by the
Employee as a result of a voluntary resignation or an Involuntary Termination
shall be communicated by a notice of termination to the other party hereto given
in accordance with this Section 10. Such notice shall indicate the specific
termination provision in this Agreement relied upon, shall set forth in
reasonable detail the facts and circumstances claimed to provide a basis for
termination under the provisions so indicated, and shall specify the termination
date (which shall be not more than 30 days after the giving of such notice). The
failure by the Employee to include in the notice any fact or circumstance which
constitutes to a showing of Involuntary Termination shall not waive any right of
the Employee hereunder or preclude the Employee from asserting such fact or
circumstance in enforcing his rights hereunder.

      11.0 Assignment. Neither this Agreement nor any rights or obligations of
any party hereunder shall be assignable without the prior written consent of the
other party hereto, except that the Company may assign this Agreement upon the
transfer of substantially all of its assets to an affiliated company.

      12.0 Benefit. This Agreement shall be binding upon and inure to the
benefit of the parties, their heirs, personal representatives, successors and
assigns.

      13.0 Invalid or Unenforceable Provisions. The invalidity or
unenforceability of any particular provision or provisions of this Agreement
shall not affect the other provisions hereof and this Agreement shall be
construed in all respects as if such invalid or unenforceable provision or
provisions were omitted.

      14.0 Limitation on Payments. In the event any payments or benefits payable
to the Employee under this Agreement or otherwise are determined by the Company
to constitute "parachute payments" within the meaning of Section 280G(b)(2)(A)
of the Code, then the Company shall reduce the total payments and benefits
payable under this Agreement until the Company determines that the total of all
"parachute payments" (as defined in Section 280G(b)(2)A) of the Code but without
regard to clause (ii) thereof) payable to the Employee are no more than 2.99
times the Employee's "base amount" (as defined in Section 280G(b)(3) of the
Code). The determination as to whether a payment constitutes a "parachute
payment" and the computation of the 2.99 limitation shall be purely within the
discretion of the Company and shall be conclusive and binding on the Company and
the Employee; provided, however, that the Employee may specify by written notice
which payments or benefits under this Agreement shall be reduced so as to meet
requirements of this Section 14.0


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      15.0 Amendments. No amendment, modification, restatement or supplement may
be made to this Agreement without the prior consent of the majority of the
members of the Compensation Committee of the Board of Directors of the Company.

      16.0  Governing Law.  This Agreement shall be governed by and construed
in accordance with the laws of the state of Illinois.

      IN WITNESS WHEREOF, the parties have affixed their signatures the day and
year first above written.


      LARRY KOSKAN                              DONLAR CORPORATION


      __________________________                By:____________________________
      Employee                                      Employer



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