Sourcing polysulfone resin from China

PSU resin: 0% UK duty

Heading 3911 includes polysulphones in primary forms. For PSU matching the listed chemical description, 3911 90 11 10 covers the specified forms containing no more than 20% additives by weight; 3911 90 11 90 covers other goods within that parent description. The purchasing examples in the table share these codes; colour alone does not decide classification.

Read from the UK Trade Tariff on 6 November 2026, both PSU lines carry 0% duty for goods from China, with no listed anti-dumping or countervailing duties and no listed suspensions. The tariff attaches import and export waste controls. Waste shipment controls apply only where the material is waste. For waste or uncertain-status material from China, confirm the applicable requirement with your customs broker before shipment.

Give your broker the chemical identity, physical form and full additive breakdown to confirm the commodity code. For a broader resin comparison, see the polycarbonate resin guide.

Specify PSU chemistry and processing grade

Name the manufacturer and exact PSU grade, intended moulding or extrusion process, natural or coloured finish, filler type and additive content. Ask for the technical datasheet, batch certificate of analysis and recommended drying and processing conditions. Agree moisture, melt viscosity, colour and mechanical acceptance criteria using named test methods.

Ask the supplier to distinguish PSU from polyethersulphone and polyphenylsulphone. Approve a sample in your own process, then retain it for comparison with delivered batches. Specify whether reprocessed material is acceptable and require disclosure of any formulation change.

Confirm with HSE the UK REACH registration position for the polymer, monomers and reactants, including any exemption and applicable composition or annual quantity thresholds. Establish the monomer information and registration position before ordering.

Worked duty example

Illustrative example, not a quote: Illustrative order: one tonne of natural PSU resin pellets under 3911 90 11 10, invoiced at £18,000 free on board, with £1,500 of freight and insurance to the UK. The customs value is £19,500. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £19,500, so it is £3,900. With no duty, the only import tax is the VAT, which a VAT-registered importer can usually reclaim. The import duty and VAT guide explains each step.

Inspection checklist

Identity: check manufacturer, grade and batch references against the approved sample and certificate of analysis.

Condition: check pellets for black specks, mixed colours, fines and foreign material; test moisture against the agreed specification.

Processing: check a retained sample in a moulding or extrusion trial for flow, surface defects and colour consistency.

Packing: check sealed liners, damaged bags and batch traceability on arrival. Agree sampling through the quality inspection guide.

What goes wrong

A supplier substitutes a different sulphone polymer or changes the filler package while keeping a similar commercial description. The approved sample then stops representing the shipment. Compare chemical identity and formulation records as well as the grade name.

Moisture, contamination and inconsistent viscosity can produce surface defects or unstable processing. Quarantine suspect batches, compare them with the retained sample and resolve the cause before blending them into production stock.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For repeat volumes, see container programmes.