Classification of Natural Rubber Varieties
Natural rubber can be categorized into two main types according to its form: solid natural rubber (film and granular rubber) and concentrated latex. In everyday use, solid natural rubber accounts for the vast majority.
According to the different manufacturing processes and shapes, film can be divided into smoke flake rubber, air-dried film, white crumpled film, brown crumpled film and so on. Smoked rubber is the most representative varieties of natural rubber, has been a large amount, widely used a rubber, smoked rubber is generally graded according to the shape, divided into special, first, second, third, fourth, fifth and so on a total of six grades, less than five is classified as an external rubber.
Granular rubber (i.e. standard rubber) is graded according to the international unified physical and chemical performance, indicators, these physical and chemical properties include impurity content, plasticity value, plasticity retention rate, nitrogen content, volatile matter content, ash content and color index and other seven, of which the content of impurities for the dominant indicators, according to the number of impurities are divided into five levels, 5L, 5, 10, 20, and 50 and so on.
