Natural rubber is primarily categorized based on its processing methods and physical forms, with several varieties including but not limited to the following:
Solid Natural Rubber (Dry Rubber):
- Smoked Sheet Rubber: Derived from tree sap, it undergoes initial processing to form thin sheets that are sun-dried. Commonly used in tire manufacturing.
- Ribbed Smoked Sheet (RSS): Similar to smoked sheet rubber but with a ribbed surface, often of slightly lower quality, suitable for less demanding rubber products.
- Crepe Rubber: Processed by coagulating and pressing the latex into large sheets, then air-dried, it's cut into various sizes for versatile use in rubber goods production.
- Latex Concentrate/Block Rubber: Through specialized processes, latex is dehydrated, coagulated, and cut into small blocks or granules, facilitating storage and transport. It's widely employed in a range of rubber products.
Concentrated Latex:
- Unfurther processed, high-concentration latex maintaining good inherent physical properties, ideal for producing latex goods like gloves, condoms, balloons, offering high elasticity and softness.
The color of natural rubber can vary from milky white to light yellow, dark yellow, or brown depending on the processing method and quality. In practical applications, to enhance specific properties or meet different requirements, natural rubber is often blended with other materials; for instance, adding carbon black to improve wear resistance and aging properties, resulting in black rubber products.
Beyond these categories, natural rubber can be further subclassified according to origin, tree species, and specific physical-chemical properties, though the aforementioned are the most common classifications.
