<PAGE>   1
                                                                   EXHIBIT 4.2


THIS WARRANT HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED, OR ANY STATE SECURITIES LAWS. IT MAY NOT BE SOLD OR OFFERED FOR SALE
EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SAID ACT AND ANY
APPLICABLE STATE SECURITIES LAW OR AN APPLICABLE EXEMPTION FROM SUCH
REGISTRATION REQUIREMENTS.


                      ------------------------------------
February 2, 2000

                        U.S. PLASTIC LUMBER CORPORATION

                      ------------------------------------

                          Common Stock Purchase Warrant

         U.S. Plastic Lumber Corporation, a Nevada corporation (the "COMPANY"),
hereby certifies that for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, HALIFAX FUND, L.P., having an
address at c/o The Palladin Group, L.P., Investment Manager, 195 Maplewood
Avenue, Maplewood, New Jersey 07040 ("PURCHASER") or any other Warrant Holder is
entitled, on the terms and conditions set forth below, to purchase from the
Company at any time beginning on the date hereof and ending on the fifth
anniversary of the Closing Date, as extended 1.5 times the number of days
between the 90th day following the Closing Date and such anniversary on which
there had been no Effective Registration, 200,000 fully paid and nonassessable
shares of Common Stock, par value $0.0001, of the Company (the "COMMON STOCK"),
at a purchase price per share of Common Stock equal to 10.09125 (the "PURCHASE
PRICE"), as the same may be adjusted pursuant to Section 5 herein.

1.       DEFINITIONS.

         (a) The term "AGREEMENT" shall mean the Convertible Debenture Purchase
Agreement dated as of February 2, 2000, between the Company and the Investors
signatory thereto.

         (b) The term "DEBENTURE" shall mean any of the Company's 5% Convertible
Debentures Due February 2, 2005.

         (c) The term "EFFECTIVE REGISTRATION" shall have the meaning specified
in the Agreement.

         (d) The term "CLOSING DATE" shall mean February 2, 2000.




<PAGE>   2



                  (e) The term "REGISTRATION RIGHTS AGREEMENT" shall mean the
Registration Rights Agreement, dated as of February 2, 2000, between the Company
and the Investor signatory thereto.

                  (f) The term "WARRANT HOLDER" shall mean the Purchaser or any
assignee of all or any portion of this Warrant.

                  (g) The term "WARRANT SHARES" shall mean the shares of Common
Stock or other securities issuable upon exercise of this Warrant.

         Capitalized terms used but not defined in this Warrant shall have the
meanings specified in the Agreement or the Debentures.

         2.       EXERCISE OF WARRANT.

         This Warrant may be exercised by the Warrant Holder, in whole or in
part, at any time and from time to time by either of the following methods:

                  (a) The Warrant Holder may surrender this Warrant, together
with the form of subscription at the end hereof duly executed by Warrant Holder
("SUBSCRIPTION NOTICE"), at the offices of the Company or any transfer agent for
the Common Stock; or

                  (b) The Warrant Holder may also exercise this Warrant, in
whole or in part, in a "cashless" or "net-issue" exercise by delivering to the
offices of the Company or any transfer agent for the Common Stock this Warrant,
together with a Subscription Notice specifying the number of Warrant Shares to
be delivered to such Warrant Holder ("DELIVERABLE SHARES") and the number of
Warrant Shares with respect to which this Warrant is being surrendered in
payment of the aggregate Purchase Price for the Deliverable Shares ("SURRENDERED
SHARES"); provided that the Purchase Price multiplied by the number of
Deliverable Shares shall not exceed the value of the Surrendered Shares. For the
purposes of this provision, each Warrant Share as to which this Warrant is
surrendered will be attributed a value equal to the fair market value (as
defined below) of the Warrant Share minus the Purchase Price of the Warrant
Share.

         In the event that the Warrant is not exercised in full, the number of
Warrant Shares shall be reduced by the number of such Warrant Shares for which
this Warrant is exercised and/or surrendered, and the Company, at its expense,
shall within three (3) Trading Days (as defined below) issue and deliver to or
upon the order of Warrant Holder a new Warrant of like tenor in the name of
Warrant Holder or as Warrant Holder (upon payment by Warrant Holder of any
applicable transfer taxes) may request, reflecting such adjusted Warrant Shares.



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<PAGE>   3



         3.       DELIVERY OF STOCK CERTIFICATES.

                  (a) Subject to the terms and conditions of this Warrant, as
soon as practicable after the exercise of this Warrant in full or in part, and
in any event within three (3) Trading Days thereafter, the Company shall
transmit the certificates of the Warrant Shares (together with any other stock
or other securities or property to which Warrant Holder is entitled upon
exercise) by messenger or overnight delivery service to reach the address
designated by such holder within three (3) Trading Days after the receipt of the
Subscription Notice ("T+3"). If such certificates are not received by the
Warrant Holder within T+3, then the Warrant Holder will be entitled to revoke
and withdraw its exercise of its Warrant at any time prior to its receipt of
those certificates.

                  In lieu of delivering physical certificates representing the
Warrant Shares deliverable upon exercise of Warrants, provided the Company's
transfer agent is participating in the Depository Trust Company ("DTC") Fast
Automated Securities Transfer ("FAST") program, upon request of the Warrant
Holder, the Company shall use its best efforts to cause its transfer agent to
electronically transmit the Warrant Shares issuable upon exercise to the Warrant
Holder, by crediting the account of Warrant Holder's prime broker with DTC
through its Deposit Withdrawal Agent Commission ("DWAC") system. The time
periods for delivery described above shall apply to the electronic transmittals
through the DWAC system. The parties agree to coordinate with DTC to accomplish
this objective. The exchange pursuant to Section 3 shall be deemed to have been
made immediately prior to the close of business on the date of the Subscription
Notice. The person or persons entitled to receive the Warrant Shares issuable
upon such exercise shall be treated for all purposes as the record holder or
holders of such Warrant Shares at the close of business on the date of the
Subscription Notice.

                  The term Trading Day means (x) if the Common Stock is listed
on the New York Stock Exchange or the American Stock Exchange, a day on which
there is trading on such stock exchange, (y) if the Common Stock is not listed
on either of such stock exchanges but sale prices of the Common Stock are
reported on an automated quotation system, a day on which trading is reported on
the principal automated quotation system on which sales of the Common Stock are
reported, or (z) if the foregoing provisions are inapplicable, a day on which
quotations are reported by National Quotation Bureau Incorporated.

                  (b) This Warrant may not be exercised as to fractional shares
of Common Stock. In the event that the exercise of this Warrant, in full or in
part, would result in the issuance of any fractional share of Common Stock, then
in such event the Warrant Holder shall be entitled to cash equal to the fair
market value of such fractional share. For purposes of this Warrant, "FAIR
MARKET VALUE" shall equal the closing trading price of the Common Stock on the
Approved Market which is the principal trading exchange or market for the Common
Stock (the "PRINCIPAL MARKET") on the date of determination or, if the Common
Stock is not listed or admitted to trading on any Approved Market, the average



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<PAGE>   4



of the closing bid and asked prices on the over-the-counter market as furnished
by any New York Stock Exchange member firm reasonably selected from time to time
by the Company for that purpose and reasonably acceptable to the Warrant Holder,
or, if the Common Stock is not listed or admitted to trading on any Approved
Market or traded over-the-counter and the average price cannot be determined a
contemplated above, the fair market value of the Common Stock shall be as
reasonably determined in good faith by the Company's Board of Directors with the
concurrence of the Warrant Holder.

         4.       (A) REPRESENTATIONS AND COVENANTS OF THE COMPANY.

                  (a) The Company shall comply with its obligations under the
Registration Rights Agreement with respect to the Warrant Shares, including,
without limitation, the Company's obligation to have filed and declared and
maintained effective a registration statement registering the Warrant Shares
under the Securities Act of 1933, as amended (the "ACT").

                  (b) The Company shall take all necessary action and
proceedings as may be required and permitted by applicable law, rule and
regulation, including, without limitation, the notification of the Principal
Market, for the legal and valid issuance of this Warrant and the Warrant Shares
to the Warrant Holder under this Warrant.

                  (c) From the date hereof through the last date on which this
Warrant is exercisable, the Company shall take all steps necessary to insure
that the Common Stock remains listed on the Principal Market.

                  (d) The Warrant Shares, when issued in accordance with the
terms hereof, will be duly authorized and, when paid for or issued in accordance
with the terms hereof, shall be validly issued, fully paid and non-assessable.
The Company has authorized and reserved for issuance to Warrant Holder the
requisite number of shares of Common Stock to be issued pursuant to this
Warrant.

                  (e) The Company shall at all times reserve and keep available,
solely for issuance and delivery as Warrant Shares hereunder, 200% of such
number of shares of Common Stock as shall from time to time be issuable
hereunder.

                  (f) With a view to making available to the Warrant Holder the
benefits of Rule 144 promulgated under the Act and any other rule or regulation
of the Securities and Exchange Commission ("SEC") that may at any time permit
Warrant Holder to sell securities of the Company to the public without
registration, the Company agrees to use its best efforts to:

                      (i) make and keep public information available, as those
                  terms are understood and defined in Rule 144, at all times;

                      (ii) file with the SEC in a timely manner all reports and
                  other documents required of the Company under the Act and the
                  Securities Exchange Act of 1934, as amended (the "EXCHANGE
                  ACT"); and



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<PAGE>   5


                      (iii) furnish to any Warrant Holder forthwith upon request
                  a written statement by the Company that it has complied with
                  the reporting requirements of Rule 144 and of the Act and the
                  Exchange Act, a copy of the most recent annual or quarterly
                  report of the Company, and such other reports and documents so
                  filed by the Company as may be reasonably requested to permit
                  any such Warrant Holder to take advantage of any rule or
                  regulation of the SEC permitting the selling of any such
                  securities without registration.

                  (B) REPRESENTATIONS AND COVENANTS OF THE PURCHASER.

                  The Purchaser shall not resell Warrant Shares, unless such
resale is pursuant to an effective registration statement under the Act or
pursuant to an applicable exemption from such registration requirements.

         5.       ADJUSTMENT OF PURCHASE PRICE AND NUMBER OF SHARES. The number
of and kind of securities purchasable upon exercise of this Warrant and the
Purchase Price shall be subject to adjustment from time to time as follows:

                  (a)   SUBDIVISIONS, COMBINATIONS AND OTHER ISSUANCES. If the
Company shall at any time after the date hereof but prior to the expiration of
this Warrant subdivide its outstanding securities as to which purchase rights
under this Warrant exist, by split-up, spin-off, or otherwise, or combine its
outstanding securities as to which purchase rights under this Warrant exist, the
number of Warrant Shares as to which this Warrant is exercisable as of the date
of such subdivision, split-up, spin-off or combination shall forthwith be
proportionately increased in the case of a subdivision, or proportionately
decreased in the case of a combination. Appropriate proportional adjustments
(decrease in the case of subdivision, increase in the case of combination) shall
also be made to the Purchase Price payable per share, so that the aggregate
Purchase Price payable for the total number of Warrant Shares purchasable under
this Warrant as of such date shall remain the same as it would have been before
such subdivision or combination.

                  (b)   STOCK DIVIDEND. If at any time after the date hereof the
Company declares a dividend or other distribution on Common Stock payable in
Common Stock or other securities or rights convertible into or exchangeable for
Common Stock ("COMMON STOCK EQUIVALENTS") without payment of any consideration
by holders of Common Stock for the additional shares of Common Stock or the
Common Stock Equivalents (including the additional shares of Common Stock
issuable upon exercise or conversion thereof), then the number of shares of
Common Stock for which this Warrant may be exercised shall be increased as of
the record date (or the date of such dividend distribution if no record date is
set) for determining which holders of Common Stock shall be entitled to receive
such dividends, in proportion to the increase in the number of outstanding
shares (and shares of Common Stock issuable upon conversion of all such
securities convertible into Common Stock) of Common Stock as a result of such
dividend, and the Purchase Price shall be proportionately reduced so that the
aggregate Purchase Price for all the Warrant Shares issuable hereunder
immediately after the record date (or on the date of such distribution, if



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<PAGE>   6



applicable) for such dividend shall equal the aggregate Purchase Price so
payable immediately before such record date (or on the date of such
distribution, if applicable). For the avoidance of doubt, the Purchaser
acknowledges that dividends paid by the Company on its Series A Preferred Stock
and Series B Preferred Stock shall not cause any of the adjustments described in
this paragraph.

                  (c)   OTHER DISTRIBUTIONS. If at any time after the date
hereof the Company distributes to holders of its Common Stock, other than as
part of its dissolution, liquidation or the winding up of its affairs, any
shares of its capital stock, any evidence of indebtedness or any of its assets
(other than Common Stock), then the number of Warrant Shares for which this
Warrant is exercisable shall be increased to equal: (i) the number of Warrant
Shares for which this Warrant is exercisable immediately prior to such event,
(ii) multiplied by a fraction, (A) the numerator of which shall be the fair
market value per share of Common Stock on the record date for the dividend or
distribution, and (B) the denominator of which shall be the fair market value
price per share of Common Stock on the record date for the dividend or
distribution minus the amount allocable to one share of Common Stock of the
value (as jointly determined in good faith by the Board of Directors of the
Company and the Warrant Holder) of any and all such evidences of indebtedness,
shares of capital stock, other securities or property, so distributed. The
Purchase Price shall be reduced to equal: (i) the Purchase Price in effect
immediately before the occurrence of any event (ii) multiplied by a fraction,
(A) the numerator of which is the number of Warrant Shares for which this
Warrant is exercisable immediately before the adjustment, and (B) the
denominator of which is the number of Warrant Shares for which this Warrant is
exercisable immediately after the adjustment.

                  (d)   MERGER, ETC. If at any time after the date hereof there
shall be a merger or consolidation of the Company with or into or a transfer of
all or substantially all of the assets of the Company to another entity, then
the Warrant Holder shall be entitled to receive upon or after such transfer,
merger or consolidation becoming effective, and upon payment of the Purchase
Price then in effect, the number of shares or other securities or property of
the Company or of the successor corporation resulting from such merger or
consolidation, which would have been received by Warrant Holder for the shares
of stock subject to this Warrant had this Warrant been exercised just prior to
such transfer, merger or consolidation becoming effective or to the applicable
record date thereof, as the case may be. The Company will not merge or
consolidate with or into any other corporation, or sell or otherwise transfer
its property, assets and business substantially as an entirety to another
corporation, unless the corporation resulting from such merger or consolidation
(if not the Company), or such transferee corporation, as the case may be, shall
expressly assume, by supplemental agreement reasonably satisfactory in form and
substance to the Warrant Holder, the due and punctual performance and observance
of each and every covenant and condition of this Warrant to be performed and
observed by the Company.

                  (e)   RECLASSIFICATION, ETC. If at any time after the date
hereof there shall be a reorganization or reclassification of the securities as
to which purchase rights under this Warrant exist into the same or a different
number of securities of any other class or classes, then the Warrant Holder
shall thereafter be entitled to receive upon exercise of this Warrant, during
the period specified herein and upon payment of the Purchase Price then in



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<PAGE>   7


effect, the number of shares or other securities or property resulting from such
reorganization or reclassification, which would have been received by the
Warrant Holder for the shares of stock subject to this Warrant had this Warrant
at such time been exercised.

                  (f)   PURCHASE PRICE ADJUSTMENT. In the event that within
twelve (12) months of the Closing Date the Company issues or sells any Common
Stock or securities which are convertible into or exchangeable for its Common
Stock or any convertible securities, or any warrants or other rights to
subscribe for or to purchase or any options for the purchase of its Common Stock
or any such convertible securities (other than shares or options issued or which
may be issued (i) pursuant to the Company's employee or director option plans,
(ii) upon exercise of options, warrants or rights outstanding on the date of the
Agreement and listed in the Company's most recent periodic report filed under
the Exchange Act, (iii) as compensation in connection with arrangements with
consultants and promoters of the Common Stock and (iv) as performance-related
compensation to individuals that are employees of entities that have been
acquired by or merged into the Company, pursuant to "earn out" provisions of the
acquisition or merger agreements pursuant to which the Company acquired such
entities) at an effective purchase price per share which is less than the
greater of the Purchase Price then in effect or the fair market value (as
defined in Section 3(b) above) of the Common Stock on the trading day next
preceding such issue or sale, then in each such case, the Purchase Price in
effect immediately prior to such issue or sale shall be reduced effective
concurrently with such issue or sale to an amount determined by multiplying the
Purchase Price then in effect by a fraction, (x) the numerator of which shall be
the sum of (1) the number of shares of Common Stock outstanding immediately
prior to such issue or sale, plus (2) the number of shares of Common Stock which
the aggregate consideration received by the Company for such additional shares
would purchase at such fair market value or, Purchase Price as the case may be,
then in effect; and (y) the denominator of which shall be the number of shares
of Common Stock of the Company outstanding immediately after such issue or sale.

                  For the purposes of the foregoing adjustment, in the case of
the issuance of any convertible securities, warrants, options or other rights to
subscribe for or to purchase or exchange for, shares of Common Stock
("CONVERTIBLE SECURITIES"), the maximum number of shares of Common Stock
issuable upon exercise, exchange or conversion of such Convertible Securities
shall be deemed to be outstanding, provided that no further adjustment shall be
made upon the actual issuance of Common Stock upon exercise, exchange or
conversion of such Convertible Securities.

                  The number of shares which may be purchased hereunder shall be
increased proportionately to any reduction in Purchase Price pursuant to this
paragraph 5(f), so that after such adjustments the aggregate Purchase Price
payable hereunder for the increased number of shares shall be the same as the
aggregate Purchase Price in effect just prior to such adjustments.



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                  In the event of any such issuance for a consideration which is
less than such fair market value and also less than the Purchase Price then in
effect, than there shall be only one such adjustment by reason of such issuance,
such adjustment to be that which results in the greatest reduction of the
Purchase Price computed as aforesaid.

         6.       NO IMPAIRMENT. The Company will not, by amendment of its
Certificate of Incorporation or through any reorganization, transfer of assets,
consolidation, merger, dissolution, issue or sale of securities or any other
voluntary action, avoid or seek to avoid the observance or performance of any of
the terms of this Warrant, but will at all times in good faith assist in the
carrying out of all such terms and in the taking of all such action as may be
necessary or appropriate in order to protect the rights of the Warrant Holder
against impairment. Without limiting the generality of the foregoing, the
Company (a) will not increase the par value of any Warrant Shares above the
amount payable therefor on such exercise, and (b) will take all such action as
may be reasonably necessary or appropriate in order that the Company may validly
and legally issue fully paid and nonassessable Warrant Shares on the exercise of
this Warrant.

         7.       NOTICE OF ADJUSTMENTS. Whenever the Purchase Price or number
of Shares purchasable hereunder shall be adjusted pursuant to Section 5 hereof,
the Company shall execute and deliver to the Warrant Holder a certificate
setting forth, in reasonable detail, the event requiring the adjustment, the
amount of the adjustment, the method by which such adjustment was calculated and
the Purchase Price and number of shares purchasable hereunder after giving
effect to such adjustment, and shall cause a copy of such certificate to be
mailed (by first class mail, postage prepaid) to the Warrant Holder.

         8.       RIGHTS AS STOCKHOLDER. Prior to exercise of this Warrant, the
Warrant Holder shall not be entitled to any rights as a stockholder of the
Company with respect to the Warrant Shares, including (without limitation) the
right to vote such shares, receive dividends or other distributions thereon or
be notified of stockholder meetings. However, in the event of any taking by the
Company of a record of the holders of any class of securities for the purpose of
determining the holders thereof who are entitled to receive any dividend (other
than a cash dividend) or other distribution, any right to subscribe for,
purchase or otherwise acquire any shares of stock of any class or any other
securities or property, or to receive any other right, the Company shall mail to
each Warrant Holder, at least 10 Trading Days prior to the date specified
therein, a notice specifying the date on which any such record is to be taken
for the purpose of such dividend, distribution or right, and the amount and
character of such dividend, distribution or right.

         9.       LIMITATION ON EXERCISE.

                  (a)   Notwithstanding anything to the contrary contained
herein, this Warrant may not be exercised by the Warrant Holder to the extent
that, after giving effect to Warrant Shares to be issued pursuant to a
Subscription Notice, the total number of shares of Common Stock deemed
beneficially owned by such holder (other than by virtue of ownership of this
Warrant, or ownership of other securities that have limitations on the holder's




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rights to convert or exercise similar to the limitations set forth herein),
together with all shares of Common Stock deemed beneficially owned by the
holder's "affiliates" (as defined in Rule 144 of the Act) that would be
aggregated for purposes of determining whether a group under Section 13(d) of
the Securities Exchange Act of 1934, as amended (the "EXCHANGE ACT") exists (an
"AGGREGATION PARTY"), would exceed 9.9% (the "RESTRICTED OWNERSHIP PERCENTAGE")
of the total issued and outstanding shares of the Company's Common Stock;
PROVIDED that (w) the Warrant Holder shall have the right at any time and from
time to time to reduce its Restricted Ownership Percentage immediately upon
notice to the Company or in the event of a Change in Control Transaction, (x)
the Warrant Holder shall have the right at any time and from time to time to
increase its Restricted Ownership Percentage or otherwise waive in whole or in
part the restrictions of this Section 9 upon 61 days' prior notice to the
Company or immediately in the event of a Change in Control Transaction, (y) the
Warrant Holder can make subsequent adjustments pursuant to (w) or (x) any number
of times from time to time (which adjustment shall be effective immediately if
it results in a decrease in the Restricted Ownership Percentage or shall be
effective upon 61 days' prior written notice or immediately in the event of a
Change in Control Transaction if it results in an increase in the Restricted
Ownership Percentage) and (z) the Warrant Holder may eliminate or reinstate this
limitation at any time and from time to time (which elimination will be
effective upon 61 days' prior notice and which reinstatement will be effective
immediately). Without limiting the foregoing, in the event of a Change in
Control Transaction, the Warrant Holder may reinstate immediately (in whole or
in part) the requirement that any increase in its Restricted Ownership
Percentage be subject to 61 days' prior written notice, notwithstanding such
Change in Control Transaction, without imposing such requirement on, or
otherwise changing the Warrant Holder's rights with respect to, any other Change
in Control Transaction. For this purpose, any material modification of the terms
of a Change in Control Transaction will be deemed to create a new Change in
Control Transaction. The term "DEEMED BENEFICIALLY OWNED" as used in this
Warrant shall exclude shares that might otherwise be deemed beneficially owned
by reason of the exercisability of the Warrants. A "CHANGE IN CONTROL
TRANSACTION" will be deemed to have occurred upon the earlier of the
announcement or consummation of a transaction or series of transactions (other
than the Merger) involving (x) any consolidation or merger of the Company with
or into any other corporation or other entity or person (whether or not the
Company is the surviving corporation), or any other corporate reorganization or
transaction or series of related transactions in which in excess of 50% of the
Company's voting power is transferred through a merger, consolidation, tender
offer or similar transaction, or (y) in excess of 50% of the Corporation's Board
of Directors consists of directors not nominated by the prior Board of Directors
of the Company, or (z) any person (as defined in Section 13(d) of the Exchange
Act) together with its affiliates and associates (as such terms are defined in
Rule 405 under the Act), beneficially owns or is deemed to beneficially own (as
described in Rule 13d-3 under the Exchange Act without regard to the 60-day
exercise period) in excess of 50% of the Company's voting power.

                  (b)   Each time (a "COVENANT TIME") the Warrant Holder makes a
Triggering Acquisition (as defined below) of shares of Common Stock (the
"TRIGGERING SHARES"), the Warrant Holder will be deemed to covenant that it will
not, during the balance of the day on which such Triggering Acquisition occurs,
and during the 61-day period beginning immediately after that day, acquire
additional shares of Common Stock pursuant to rights-to-acquire existing at that




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<PAGE>   10


Covenant Time, if the aggregate amount of such additional shares so acquired
(without reducing that amount by any dispositions) would exceed (x) the
Restricted Ownership Percentage of the number of shares of Common Stock
outstanding at that Covenant Time (including the Triggering Shares) minus (y)
the number of shares of Common Stock actually owned by the Warrant Holder at
that Covenant Time (regardless of how or when acquired, and including the
Triggering Shares). A "TRIGGERING ACQUISITION" means the giving of a
Subscription Notice or any other acquisition of Common Stock by the Warrant
Holder or an aggregation party; provided, however, that with respect to the
giving of such Subscription Notice, if the associated issuance of shares of
Common Stock does not occur, such event shall cease to be a Triggering
Acquisition and the related covenant under this paragraph shall terminate. At
each Covenant Time, the Warrant Holder shall be deemed to waive any right it
would otherwise have to acquire Common Shares to the extent that such
acquisition would violate any covenant given by the Warrant Holder under this
paragraph. For the avoidance of doubt:

                        (i)   The covenant to be given pursuant to this
                  paragraph will be given at every Covenant Time and shall be
                  calculated based on the circumstances then in effect. The
                  making of a covenant at one Covenant Time shall not terminate
                  or modify any prior covenants.

                        (ii)  The Warrant Holder may therefore from time to time
                  be subject to multiple such covenants, each one having been
                  made at a different Covenant Time, and some possibly being
                  more restrictive than others. The Warrant Holder must comply
                  with all such covenants then in effect.

                  (c)   The delivery of a Subscription Notice by the Warrant
Holder shall be deemed a representation by the Warrant Holder that it is in
compliance with this Section 9.

         10.      REPLACEMENT OF WARRANT. On receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant and, in the case of any such loss, theft or destruction of this
Warrant, on delivery of an indemnity agreement or security reasonably
satisfactory in form and amount to the Company or, in the case of any such
mutilation, on surrender and cancellation of such Warrant, the Company at its
expense promptly will execute and deliver, in lieu thereof a new Warrant of like
tenor.

         11.      SPECIFIC PERFORMANCE; CONSENT TO JURISDICTION; CHOICE OF LAW.

                  (a)   The Company and the Warrant Holder acknowledge and agree
that irreparable damage would occur in the event that any of the provisions of
this Warrant were not performed in accordance with their specific terms or were
otherwise breached. It is accordingly agreed that the parties shall he entitled
to an injunction or injunctions to prevent or cure breaches of the provisions of



                                       10
<PAGE>   11


this Warrant and to enforce specifically the terms and provisions hereof, this
being in addition to any other remedy to which either of them may be entitled by
law or equity.

                  (b)   Each of the Company and the Warrant Holder (i) hereby
irrevocably submits to the exclusive jurisdiction of the state and federal
courts located in New York County, New York for the purposes of any suit, action
or proceeding arising out of or relating to this warrant and (ii) hereby waives,
and agrees not to assert in any such suit, action or proceeding, any claim that
it is not personally subject to the jurisdiction of such court, that the suit,
action or proceeding is brought in an inconvenient forum or that the venue of
the suit, action or proceeding is improper. Each of the Company and the Warrant
Holder consents to process being served in any such suit, action or proceeding
by mailing a copy thereof to such party at the address in effect for notices to
it under this Warrant and agrees that such service shall constitute good and
sufficient service of process and notice thereof. Nothing in this paragraph
shall affect or limit any right to serve process in any other manner permitted
by applicable law.

                  (c)   The Company and the Warrant Holder irrevocably waive
their right to trial by jury.

                  (d)   This Warrant shall be governed by and construed and
enforced in accordance with the internal laws of the State of New York
applicable to contracts executed and to be performed entirely within such State.

         12.      ENTIRE AGREEMENT; AMENDMENTS. This Warrant, the Exhibits
hereto and the provisions contained in the Agreement or the Registration Rights
Agreement or the Debentures contain the entire understanding of the parties with
respect to the matters covered hereby and thereby and, except as specifically
set forth herein and therein, neither the Company nor the Warrant Holder makes
any representation, warranty, covenant or undertaking with respect to such
matters. No provision of this Agreement may be waived or amended other than by a
written instrument signed by the party against whom enforcement of any such
amendment or waiver is sought.

         13.      NOTICES. Any notice or other communication required or
permitted to be given hereunder shall be in writing and shall be effective (a)
upon hand delivery or delivery by telex (with correct answer back received),
telecopy or facsimile at the address or number designated below (if delivered on
a business day during normal business hours where such notice is to be
received), or the first business day following such delivery (if delivered other
than on a business day during normal business hours where such notice is to be
received) or (b) on the second business day following the date of mailing by
express courier service, fully prepaid, addressed to such address, or upon
actual receipt of such mailing, whichever shall first occur. The addresses for
such communications shall be:



                                       11
<PAGE>   12


                  to the Company:

                                    U.S. Plastic Lumber Corporation
                                    2300 Glades Road
                                    Suite 440 West
                                    Boca Raton, Florida 33431
                                    Attention:       Bruce Rosetto
                                    Facsimile:       (561) 394-5335

                  to the Warrant Holder:

                                    Halifax Fund, L.P.
                                    c/o The Palladin Group, L.P.
                                    Investment Manager
                                    195 Maplewood Avenue
                                    Maplewood, NJ  07040
                                    Attention:       Robert Chender
                                    Facsimile:       (973) 313-6491

                  with copies to:

                                    Kleinberg, Kaplan, Wolff & Cohen, P.C.
                                    551 Fifth Avenue, 18th Floor
                                    New York, New York  10176
                                    Attention:       Stephen M. Schultz, Esq.
                                    Facsimile:       (212) 986-8866

Either party hereto may from time to time change its address for notices under
this Section 13 by giving at least 10 days' prior written notice of such changed
address to the other party hereto.

         14.      MISCELLANEOUS. This Warrant and any term hereof may be
changed, waived, discharged or terminated only by an instrument in writing
signed by the party against which enforcement of such change, waiver, discharge
or termination is sought. The headings in this Warrant are for purposes of
reference only, and shall not limit or otherwise affect any of the terms hereof.
The invalidity or unenforceability of any provision hereof shall in no way
affect the validity or enforceability of any other provision.

         15.      ASSIGNMENT. This Warrant may be transferred or assigned, in
whole or in part, at any time and from time to time by the then Warrant Holder
by submitting this Warrant to the Company together with a duly executed
Assignment in substantially the form and substance of the Form of Assignment
which accompanies this Warrant and, upon the Company's receipt hereof, and in
any event, within three (3) business days thereafter, the Company shall issue a
Warrant to the Warrant Holder to evidence that portion of this Warrant, if any,
as shall not have been so transferred or assigned.



                                       12
<PAGE>   13


Dated:   February 2, 2000           U.S. PLASTIC LUMBER CORPORATION



                                     By: /s/ Bruce C. Rosetto
                                        ----------------------------------
                                     Name: Bruce C. Rosetto
                                     Title: Vice President and General Counsel

CORPORATE SEAL

Attest:

By: /s/
   -----------------------------------


               (SIGNATURE PAGE OF U.S. PLASTIC LUMBER CORPORATION
                         COMMON STOCK PURCHASE WARRANT)



                                       13
<PAGE>   14


                              (SUBSCRIPTION NOTICE)
                            FORM OF WARRANT EXERCISE
                   (TO BE SIGNED ONLY ON EXERCISE OF WARRANT)

TO:               U.S. PLASTIC LUMBER CORPORATION
ATTN:             SECRETARY

         The undersigned, the holder of the within Warrant, hereby irrevocably
elects to exercise this Warrant:

___ (A)  for, and to purchase thereunder,             shares of Common Stock of
         U.S. Plastic Lumber Corporation, a Nevada corporation (the
         "Common Stock"), and herewith, or by wire transfer, makes payment
         of $         therefor; or

___ (B)  in a "cashless" or "net-issue exercise" for, and to purchase
         thereunder, shares of Common Stock, and herewith makes payment
         therefor with Surrendered Warrant Shares.

The undersigned requests that the certificates for such shares be issued in the
name of, and

___ (A)  delivered to                   , whose address is              ; or

___ (B)  electronically transmitted and credited to the account of            ,
         undersigned's prime broker (Account No.                   ) with
         Depository Trust Company through its Deposit Withdrawal Agent
         Commission system.

Dated:___________________________           ___________________________________
                                            (Signature must conform to name of
                                             holder as specified on the face of
                                             the Warrant)

                                            ___________________________________
                                                      (Address)

                                            Tax Identification Number:_________



                                       14
<PAGE>   15



                               FORM OF ASSIGNMENT
                   (TO BE SIGNED ONLY ON TRANSFER OF WARRANT)

For value received, the undersigned hereby sells, assigns, and transfers unto
_______________________ the right represented by the within Warrant to purchase
____________________ shares of Common Stock of U.S. PLASTIC LUMBER CORPORATION,
a Nevada corporation, to which the within Warrant relates, and appoints
__________________ Attorney to transfer such right on the books of U.S. PLASTIC
LUMBER CORPORATION, a Nevada corporation, with full power of substitution of
premises.

Dated: ___________________________          ___________________________________
                                            (Signature must conform to name of
                                             holder as specified on the face of
                                             the Warrant)

                                            ___________________________________
                                                        (Address)


Signed in the presence of:


__________________________________


                                       15