Natural rubber latex concentrate - Centrifuged or creamed, ammonia-preserved types - Specifications
1Key Takeaways
This document gives specifications for natural rubber latex concentrate types which are preserved wholly or in part with ammonia and which have been produced by centrifuging or creaming.
2Expert Interpretation
An in-depth interpretation of the seventh edition of ISO 2004:2024, the international standard for ammonia-preserved centrifuged/creamed natural latex concentrate, covering HA/LA/MA type technical indicators, test methods and major revisions and changes, and providing a comparison table of key parameters such as metal content and mechanical stability and implementation recommendations.
Analysis of the core content of the standard
ISO 2004:2024 standard defines the technical specifications for three types of products for ammonia-preserved natural concentrated latex produced by the centrifugation method and the paste method:
| Type | Preservation method | Alkalinity range (NH3) | Total solid content |
|---|---|---|---|
| HA type | Pure ammonia preservation | ≥0.60% | ≥61.0% |
| LA type | Composite preservative | ≤0.29% | ≥65.0% |
| MA type | Composite preservative | 0.30-0.59% | ≥65.0% |
Comparison of key technical indicators
The main revisions of the 2024 version include: changing the XA type to MA type, adjusting the labeling of the total solid content of the paste latex (such as changing the HA type from a fixed 65.0% to "65.0% or agreed by both parties"), and updating the copper content detection standard to ISO 6101-3.
Key quality requirements: Mechanical stability of all types of latex must be ≥650 seconds (ISO 35), copper/manganese content must be ≤8mg/kg (ISO 6101-3/7780), and coagulant content must be ≤0.02% (ISO 706).
Implementation and application recommendations
- Test cycle control: Mechanical stability data needs to be measured after 21-35 days of latex maturation
- Metal pollution prevention and control: It is recommended to establish a heavy metal monitoring system in combination with ISO 6101-3 standard
- Commercial terms negotiation: Indicators such as volatile fatty acids (VFA) and KOH value can be agreed upon separately with the transaction parties
Standard evolution analysis
Compared with the 2017 version, this revision reflects the technological development of the industry: composite preservatives are more commonly used (newly added MA type), and detection methods are closer to modern technologies such as atomic absorption spectroscopy, while giving greater flexibility to commercial cooperation.