The tariff classification and country of origin of a polybutylene succinate (PBS)-starch composite

N352351 March 23, 2026 CLA-2-39:OT:RR:NC:N5:137 CATEGORY: Classification; Origin TARIFF NO.: 3907.99.5050 Glenn Page Foreign Trade Zone Solutions LLC PO Box 483 Greenland, NH 03840 RE: The tariff classification and country of origin of a polybutylene succinate (PBS)-starch composite Dear Mr. Page: In your letter dated August 13, 2025, you requested a tariff classification and country of origin determination ruling on behalf of your client, Noir Materials, Inc. The documentation that was supplied with your request was sent to our Lab and Scientific Services Division for review. The review is now complete. The product under consideration is referred to as a biopolymer-starch composite. It is noted to be a polybutylene succinate (PBS) - corn starch composite material. The material will be used to manufacture compostable products and high-performance composites. Chinese origin PBS is shipped to Taiwan. In Taiwan, two powder mixtures are prepared. Powder Mixture 1 is comprised of Taiwanese origin corn starch and Triethyl Citrate (TEC). The starch is pre-weighed and loaded into a blender. The TEC is gravimetrically sprayed onto the starch in the blender. Once the TEC addition is complete, the two components are blended thoroughly. Powder Mixture 2 is comprised of Taiwanese origin Dicumyl Peroxide, Sorbitol, Iron Gluconate and Propyl Gallate. The components are pre-weighed and added to the blender where they are thoroughly blended. Three feeders are positioned over the feed hopper of the extruder. Feeder 1 is loaded with Chinese PBS, Feeder 2 is loaded with Powder Mixture 1 and Feeder 3 is loaded with Powder Mixture 2. The feeders have been calibrated to the bulk density and programmed with target rates so that the materials are fed at specific formula ratios. The extruded melt strand is strung up to ride through the shallow water trough to be cooled for cutting. An air knife blows off excess water. The product is pulled through a pelletizer with a rotating knife. The pellets are then loaded into a forced air desiccated dryer. Finally, they are packaged while hot and heat sealed for air tightness. Documentation suggests that the process above is a reactive blending process which involves transesterification, plasticization, and polymer crosslinking which results in a chemically integrated and functionally distinct material from the initial PBS. Lab review noted that the process does not change the chemical properties of the PBS and does not render it suitable for a specific use. The Explanatory Notes (ENs), although neither dispositive nor legally binding, provide a commentary on the scope of each heading of the HTSUS, and are the official interpretation of the Harmonized System at the international level. See T.D. 89-80, 54 Fed. Reg. 35127, 35128 (Aug. 23, 1989). The ENs for Chapter 39, specifically related to polymers in primary forms states: “In addition to substances necessary for “curing” (such as hardeners (crosslinking agents) or other coreactants and accelerators), these liquids or pastes may contain other materials such as plasticisers, stabilisers, fillers and colouring matter, chiefly intended to give the finished products special physical properties or other desirable characteristics.” The applicable subheading for the polybutylene succinate (PBS)- corn starch composite will be 3907.99.5050, Harmonized Tariff Schedule of the United States (HTSUS), which provides for polyacetals, other polyethers and epoxide resins, in primary forms; polycarbonates, alkyd resins, polyallyl esters and other polyesters, in primary forms: other polyesters: other: other: other. The general rate of duty will be 6.5 percent ad valorem. The duties cited above are current as of this ruling’s issuance. Duty rates are provided for your convenience and are subject to change. The text of the most recent HTSUS and the accompanying duty rates are provided at https://hts.usitc.gov/. This ruling does not address the applicability of any additional duties, taxes, fees, exactions and/or other charges, which may apply to the goods discussed herein. This includes, but is not limited to, tariffs and other duties as provided for in Subchapter III to Chapter 99, HTSUS. Thus, for example, in addition to the classification stated above, the merchandise covered by this ruling may also need to be reported with either the Chapter 99 provision under which an additional tariff applies or one of the Chapter 99 provisions covering exceptions to such tariffs. For further information to assist with the importation process, please refer to the frequently updated Cargo Systems Messaging Service (CSMS) messages at https://www.cbp.gov/trade/automated/cargo-systems-messaging-service and the Trade Remedies page at https://www.cbp.gov/trade/programs-administration/trade-remedies. When determining the country of origin, the substantial transformation analysis is applicable. See, e.g., Headquarters Ruling Letter (“HQ”) H301619, dated November 6, 2018. The test for determining whether a substantial transformation will occur is whether an article emerges from a process with a new name, character, or use different from that possessed by the article prior to processing. See Texas Instruments Inc. v. United States, 681 F.2d 778 (C.C.P.A. 1982). This determination is based on the totality of the evidence. See National Hand Tool Corp. v. United States, 16 C.I.T. 308 (1992), aff’d, 989 F.2d 1201 (Fed. Cir. 1993). Lab review noted that the processing in Taiwan does not change the chemical properties of the PBS and does not render it suitable for a specific use. It is the opinion of this office that the processing of the PBS in Taiwan does not result in a substantial transformation. Therefore, the country of origin of the product will be China. The holding set forth above applies only to the specific factual situation and merchandise description as identified in the ruling request. This position is clearly set forth in Title 19, Code of Federal Regulations (CFR), Section 177.9(b)(1). This section states that a ruling letter is issued on the assumption that all of the information furnished in the ruling letter, whether directly, by reference, or by implication, is accurate and complete in every material respect. In the event that the facts are modified in any way, or if the goods do not conform to these facts at time of importation, you should bring this to the attention of U.S. Customs and Border Protection (CBP) and submit a request for a new ruling in accordance with 19 CFR 177.2. Additionally, we note that the material facts described in the foregoing ruling may be subject to periodic verification by CBP. This ruling is being issued under the provisions of Part 177 of the Customs and Border Protection Regulations (19 C.F.R. 177). A copy of the ruling or the control number indicated above should be provided with the entry documents filed at the time this merchandise is imported. If you have any questions regarding the ruling, please contact National Import Specialist Christina Allen at julie.c.allen@cbp.dhs.gov. Sincerely, (for) James Forkan Designated Official Performing the Duties of the Division Director National Commodity Specialist Division