As filed with the U.S. Securities and Exchange Commission on December 14, 2009

Registration No. 333-162248

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Amendment No. 5

to

Form S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Polymer Holdings LLC*

(Exact name of Registrant as specified in its charter)

15710 John F. Kennedy Blvd.

Suite 300

Houston, TX 77032

Telephone: (281) 504-4700

(Address including zip code, telephone number, including area code, of Registrant’s Principal Executive Offices)

Stephen W. Duffy, Esq.

General Counsel

Polymer Holdings LLC

15710 John F. Kennedy Blvd.

Suite 300

Houston, Texas 77032

Telephone: (281) 504-4700

Telecopy: (281) 504-4743

(Name, address including zip code, telephone number, including area code, of agent for service)

Copies To:

Approximate date of commencement of proposed sale to the public: As soon as practicable after the effective date hereof.

If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act, check the following box.  ¨

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act (Check one):

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

CALCULATION OF REGISTRATION FEE

* Polymer Holdings LLC, a limited liability company organized under the laws of Delaware, is the registrant filing this Registration Statement with the Securities and Exchange Commission. Prior to the closing of this offering, Polymer Holdings LLC will be converted into a corporation organized under the laws of Delaware, pursuant to the Delaware Limited Liability Company Act Section 18-216 and the Delaware General Corporation Law Section 265. The securities issued to investors in connection with this offering will be shares of common stock in that corporation, which will be named Kraton Performance Polymers, Inc.

EXPLANATORY NOTE

This Pre-Effective Amendment No. 5 to the Registration Statement on Form S-1 (File No. 333-162248) of Polymer Holdings LLC is filed for the purpose of adding exhibits to such Registration Statement and amending the Exhibit Index, which is incorporated by reference by “Part II — Item 16. Exhibits and Financial Statement Schedules,” and completing “Part II — Item 13. Other Expenses of Issuance and Distribution.”

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Estimated expenses payable in connection with the sale of the common stock in this offering are as follows:

We will bear all of the expenses shown above.

The Delaware General Corporation Law and our certificate of incorporation and bylaws provide for indemnification of our directors and officers for liabilities and expenses that they may incur in such capacities. In general, directors and officers are indemnified with respect to actions taken in good faith in a manner reasonably believed to be in, or not opposed to, our best interests, and with respect to any criminal action or proceeding, actions that the indemnitee had no reasonable cause to believe were unlawful. Please see our certificate of incorporation, which is filed as Exhibit 3.1 to this registration statement and our bylaws, which are filed as Exhibit 3.2 to this registration statement.

We intend to enter into indemnification agreements with our officers and directors. The indemnification agreements will provide our officers and directors with further indemnification to the maximum extent permitted by the Delaware General Corporation Law. The underwriting agreement filed as Exhibit 1.1 to this registration statement also provides that the underwriters are obligated, under certain circumstances, to indemnify our directors, officers and controlling persons against certain liabilities, including liabilities under the Securities Act. Please see the form of underwriting agreement filed as Exhibit 1.1 to this registration statement.

We currently maintain a directors’ and officers’ liability insurance policy.

Prior to the closing of this offering, Polymer Holdings LLC, a Delaware limited liability company, will convert into a Delaware corporation to be named Kraton Performance Polymers, Inc., and all of the outstanding membership interests of Polymer Holdings LLC held by TJ Chemical will convert into 19,325,311 shares of common stock of Kraton Performance Polymers, Inc.

(a) Exhibits: The list of exhibits is set forth in beginning on page II-6 of this Registration Statement and is incorporated herein by reference.

(b) Financial Statement Schedules: No financial statement schedules are provided because the information called for is not applicable or is shown in the financial statements or notes thereto.

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* (f) The undersigned registrant hereby undertakes to provide to the underwriters at the closing specified in the underwriting agreement, certificates in such denominations and registered in such names as required by the underwriters to permit prompt delivery to each purchaser.

* (h) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers, and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer, or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer, or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

* (i) The undersigned registrant hereby undertakes that:

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant has duly caused this Amendment No. 5 to the registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Houston, State of Texas on December 14, 2009.

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed below by the following persons in the capacities and on the dates indicated.

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EXHIBIT INDEX

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