Sourcing MBT rubber accelerator from China

A flat duty for mercaptobenzothiazole

Read from the UK Trade Tariff on 18 October 2026, commodity code 2934 20 20 00 carries 6% duty for goods from China. No anti-dumping or countervailing measure or tariff suspension is listed. Heading 2934 covers nucleic acids and other heterocyclic compounds; this particular line names mercaptobenzothiazole, its salts and the related disulphide. Only this supplied commodity line directly covers the product in this guide.

The tariff attaches an export waste control to this line. The importer should confirm its relevance with their customs broker. Waste shipment controls only apply where the material is waste; if buying recovered or rejected material from China, confirm its status and the applicable requirements before shipment.

Give your broker the chemical identity, salt form, composition and any oil or carrier treatment before confirming the commodity code. Do not assume a formulated accelerator preparation uses the same code as the substance. See the wider heterocyclic compounds guide for neighbouring products.

Specify the accelerator, treatment and batch tests

Specify mercaptobenzothiazole rather than accepting a general description such as benzothiazole accelerator. Agree the chemical identity, salt form, assay, impurity profile, melting range and moisture acceptance criteria. State whether you require powder, oil-treated material or granules, and record any added oil or carrier in the specification.

Agree particle-size testing and compare the sample with your approved material in a rubber-compounding trial. Ask for a batch certificate of analysis and an English safety data sheet. For Great Britain, confirm the applicable UK REACH registration responsibilities and any only-representative coverage with HSE. Everyone in the supply chain is responsible for correct labelling and packaging before chemicals are placed on the market.

Worked duty example

Illustrative example, not a quote: Illustrative order: 5 tonnes of mercaptobenzothiazole rubber accelerator under 2934 20 20 00, invoiced at £15,000 free on board, with £1,500 of freight and insurance to the UK. The customs value is £16,500. Duty at 6% is £990. Import VAT at 20% is charged on the customs value plus duty, £17,490, so it is £3,498. Import taxes total £4,488; a VAT-registered importer can usually reclaim the VAT, so the lasting cost is the £990 of duty. The import duty and VAT guide explains each step.

Inspection checklist

Identity: match the label, certificate and specification; confirm the substance and salt form using infrared comparison and melting range.

Assay: independently check assay and impurities against the agreed limits, using the same test method agreed for supplier certificates.

Physical form: check particle size, moisture, oil treatment, granule consistency, caking and excessive dust against the approved sample.

Packing: check seals, leakage, batch identification and label agreement with the English safety data sheet; inspect the packaging specified for the shipment.

What goes wrong

A supplier can offer the right product name but a different salt form, treatment or impurity profile. Material that meets assay alone can still cake, create excessive dust or disperse differently in your compound. Require written approval before changes to synthesis route, treatment or packing.

Mercaptobenzothiazole is a skin sensitiser and very toxic to aquatic life, as described in the wider guide. Review the English safety data sheet before handling samples. Keep suspect batches separate while identity, moisture and assay are checked; use testing and certification support to agree the laboratory brief.

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.