【国外标准】 Standard Specification for Natural Rubber (NR) Technical Grades

4.1 The general end-use quality of manufactured rubber products depends on the physical and chemical properties of the rubber.AbstractThis specification covers the minimum physical and chemical requirements for five technical grades of raw natural rubber. Materials are classified into grades according to retained dirt content, ash content, volatile matter content, nitrogen content, initial plasticity, plasticity retention index, color index, and Mooney viscosity. Skim rubber is not permitted in any grade.1.1 This specification covers minimum physical and chemical quality requirements or specifications for five grades of raw natural rubber.1.2 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.