ARTICLE I AMENDMENTS TO INDENTURE

Exhibit 4.1

SUPPLEMENTAL INDENTURE NO. 2, dated as of June 21, 2013 (this “Supplemental Indenture”), by and among Chemtura Corporation, a Delaware corporation (the “Company”), the guarantors listed on the signature pages hereto (the “Guarantors”) and U.S. Bank National Association, as trustee (in such capacity and not in its individual capacity, the “Trustee”).

WHEREAS, there has heretofore been executed and delivered to the Trustee an Indenture, dated as of August 27, 2010, as amended by Supplemental Indenture No. 1, dated as of November 10, 2010 (as so amended, the “Indenture”), providing for the issuance of the Company’s 7.875% Senior Notes due 2018 (the “Notes”);

WHEREAS, Section 9.02 of the Indenture provides that the Company, the Guarantors and the Trustee may amend the Indenture with the consent of the Holders of at least a majority in aggregate principal amount of the Notes then outstanding (the “Requisite Consents”), subject to certain limitations set forth in the Indenture;

WHEREAS, the Company and the Guarantors have duly authorized the execution and delivery of this Supplemental Indenture;

WHEREAS, the Company has offered to purchase for cash any and all of the outstanding Notes (the “Tender Offer”), upon the terms and subject to the conditions set forth in the Company’s Offer to Purchase and Consent Solicitation Statement, dated June 10, 2013, as may be amended, supplemented or modified from time to time (the “Offer to Purchase”);

WHEREAS, in connection with the Tender Offer, the Company has also solicited consents from the Holders of the Notes to certain proposed amendments (the “Proposed Amendments”) to the Indenture as described in the Offer to Purchase and set forth in Article I of this Supplemental Indenture, with the operation of such Proposed Amendments being subject to the satisfaction or waiver by the Company of the conditions to the Tender Offer and the acceptance by the Company for purchase and payment of the Notes validly tendered and not validly withdrawn pursuant to the Tender Offer;

WHEREAS, the Company has received and delivered to the Trustee the Requisite Consents to effect the Proposed Amendments in accordance with Section 9.02 of the Indenture;

WHEREAS, all things necessary to make this Supplemental Indenture a valid agreement, in accordance with its terms, have been complied with or have been performed or done; and

WHEREAS, pursuant to the terms of the Tender Offer to which this Supplemental Indenture relates, a consent payment will be made to certain Holders of the Notes who tender their Notes and deliver their consents to the Proposed Amendments.

NOW THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Company, the Guarantors and the Trustee mutually covenant and agree for the equal and ratable benefit of the Holders of the Notes as follows:

ARTICLE I

AMENDMENTS TO INDENTURE

ARTICLE II

MISCELLANEOUS

2

[Signature Pages Follow]

3

IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed as of the date first written above.

[Signature Page to Supplemental Indenture No. 2]

[Signature Page to Supplemental Indenture No. 2]