China Amines Co., Limited

For buyers working with China Amines Co., Limited, a clear specification for dimethylamine 40% aqueous solution starts with the meaning of each percentage.

A document may report solution concentration, individual impurities, or purity on a water-free basis. Before comparing figures, establish what material each calculation includes.

Read 40% as a solution concentration

When expressed as 40.0% w/w, the value means 40.0 kg of dimethylamine in every 100 kg of supplied solution.

Manufacturer specifications identify DMA 40% as an aqueous product and state an assay requirement. For example, Thermo Scientific publishes a 39.0–41.0% range for one of its grades.

Use the agreed specification and accepted batch assay for purchasing calculations.

Ask how water-free purity is defined

A water-free result uses a calculation basis that excludes water. Ask the supplier to identify the components included, the analytical method, and the calculation used.

For illustration, consider a hypothetical 100 kg mixture containing 40.0 kg DMA, 0.1 kg other non-water components, and 59.9 kg water.

DMA represents 40.0% of the complete mixture, but approximately 99.75% of its non-water portion:

40.0 ÷ 40.1 × 100 ≈ 99.75%

Both figures describe the same hypothetical mixture using different denominators.

Keep analytical results with their definitions

If a report lists chromatographic purity, request its reporting basis before interpreting it as solution concentration.

A purchasing specification can assign different methods to different parameters. Eastman’s DMA 40% specification, for example, uses titration for DMA assay and gas chromatography for named impurities.

Preserve the method, units, and reporting basis beside each result.

Compare quotations using the supplied solution

State whether the quotation applies to net solution weight or contained DMA.

For a shipment of 1,000 kg at exactly 40.0% w/w, the contained DMA quantity is 400 kg. Use the solution assay for this calculation; clarify any separate purity statement with the supplier.

This gives purchasing and production teams a consistent quantity basis.

Request clearly defined DMA 40% documentation

Send China Amines Co., Limited your required concentration range, impurity limits, reporting requirements, quantity, packaging preference, and destination.

Include any water-free purity requirement with its definition so the proposed documentation can be reviewed accurately.

Inquiries: info@chinaamines.com

Technical references

• Thermo Scientific — Dimethylamine, 40% w/w Aqueous Solution: Product Specification
• Eastman — Dimethylamine 40% Aqueous Solution: Sales Specification T51012