The US trade policy towards China has been further intensified. On April 8, 2026, the US Department of Commerce issued a final anti-dumping ruling on MDI (monomeric diisocyanate) exported from China, with the highest tax rate reaching 159.04%. When combined with existing tariffs, the overall tax burden even exceeds 200%, indicating that the export channels for relevant Chinese products to the US have been almost completely blocked. This incident not only impacts the chemical industry but also signals a new development in the Sino-US trade game.

On April 8, 2026, the U.S. Department of Commerce issued an announcement, making a positive final determination on anti-dumping duties for MDI imported from China. The ruling set the anti-dumping duty rate for Chinese producers and exporters at 85.11% to 159.04%. This product primarily involves goods under U.S. Harmonized Tariff Schedule (HTS) codes 2929.10.8010 and 3909.31.0000. MDI is a core raw material for the production of polyurethane, widely used in insulation materials, automotive parts, construction, home appliances, synthetic leather, adhesives, and other fields, and is known in the industry as "industrial MSG". Due to its importance, this product has always been a key link in the global chemical industry chain. It is worth noting that this anti-dumping duty is not "starting from scratch". Prior to this, Chinese MDI exports to the United States had already borne multiple tariffs: a basic tariff of 6.5%, a Section 301 tariff of 25%, and an additional tariff of 10% that is still in effect, with a cumulative tax burden of 41.5%. After adding the anti-dumping duty on top of this, the comprehensive tariff cost will soar to 126.61% to 200.54%. What does this tax rate mean? According to data from 2024, the United States imported approximately $240 million worth of MDI from China. Under the pressure of tariffs exceeding 100%, Chinese products will completely lose their competitiveness in price, and the end-user procurement cost may even double. For American buyers, switching to domestic or other countries for supply has become almost an inevitable choice.

From an industry perspective, this move not only affects Chinese export enterprises but also reshapes the domestic supply structure in the United States. Currently, the MDI production capacity in the United States is mainly concentrated in the hands of a few large enterprises, which have long relied on imports to supplement the supply-demand gap. High tariffs will force downstream enterprises to turn to alternative sources in the United States or Europe, the Middle East, and other regions, leading to the restructuring of the supply chain. More notably, this case reflects the changing trend of U.S. trade policy towards China: on the one hand, it has shifted from the past "comprehensive tax increase" to "precise strikes". Through trade remedy tools such as anti-dumping and anti-subsidy measures, targeted pressure is exerted on specific industries. On the other hand, through the "superposition of multiple layers of tariffs", substantial market barriers are formed within a compliant framework, rendering the target products completely uncompetitive in terms of price. At the same time, the industry orientation behind the policy has become increasingly evident. MDI is a technology- and capital-intensive industry, and high tariffs are not only a trade measure but are also seen as a tool to promote the "de-sinicization" of the supply chain. By restricting imports, downstream enterprises are forced to adjust their procurement structure and strengthen domestic or allied supply chains. Furthermore, geopolitical factors are also continuously increasing in importance. The United States has recently released a more stringent signal, stating that if China provides military support to relevant parties in the Middle East situation, it may impose additional tariffs of up to 50% on Chinese goods. Although these statements have not yet been implemented, they have further exacerbated market uncertainty. Overall, the final ruling on the anti-dumping of MDI is not only a single trade measure but also an epitome of the current changes in the international trade environment. Against the backdrop of increasingly refined tariff tools and the continuous superposition of political factors, enterprises are no longer facing short-term fluctuations but long-term structural adjustment pressures.