Natural rubber - Terminology
1 Scope
This standard specifies the terms of natural rubber. It is applicable to those terms in general use throughout the natural rubber industry.
Unless otherwise specified, all terms are nouns.
2 Category and source of rubber
2.1
polymer
substance composed of molecules characterized by the multiple repetition of one or more species of atoms or groups of atoms (constitutional repeating units) linked to each other in amounts sufficient to provide a set of properties that do not vary markedly with the addition of one or a few of the constitutional repeating units (IUPAC definition)
Note: GB/T 9881-2003, definition 252 modified.
2.1.1
elastomer
macromolecular material which returns rapidly to approximately its initial dimensions and shape after substantial deformation by a weak stress and release of the stress
[GB/T 9881-2003, definition 111]
2.1.2
rubber
elastomer which may be or has been modified into a certain state, in which it is basically insoluble (but can swell) in boiling solvents such as benzene, methyl ethyl ketone and ethanol-toluene azeotrope and it is hard to be re-molded into a fixed shape by heating and proper pressurization
[GB/T 9881-2003, definition 287]
Note: The modified rubber can be stretched to twice its original length at standard room temperature (18℃ ~ 29℃) without diluent, and kept for 1 min. It can recover to less than 1.5 times its original length within 1 min when the stress is removed.
2.1.2.1
synthetic rubber
rubber produced by one or more monomers
[GB/T 9881-2003, definition 334]
2.1.2.2
natural rubber
thermoplastic substance with rubber hydrocarbon mainly of cis-1,4-polyisoprene, obtained from the botanical source Hevea brasiliensis and rubber plants such as rubber rattan or rubber grass
Note: GB/T 9881-2003, definition 217 modified.
2.1.2.3
wild rubber
rubber collected from plants other than Hevea brasiliensis
Note 1: In principle, the rubber collected from natural plants in nature belongs to natural rubber. However, most of the plants other than Hevea brasiliensis are in the wild state because of their difficulties in transplanting, their rubber's lack of application value or their low yield. Therefore, the term "natural rubber" mainly refers to Hevea brasiliensis and cis-1,4-polyisoprene collected from rubber rattan or rubber grass, while other plant rubbers are collectively referred to as wild rubber.
Note 2: More than 30 kinds of wild rubber have been found, and only a few representative wild rubbers are listed here.
2.1.2.3.1
balata
hard thermoplastic substance containing approximately equal proportions of trans-1,4-polyisoprene and resin, obtained from the arbor Mimusops globosa native to South America
Note: GB/T 9881-2003, definition 29 modified.
2.1.2.3.2
Para rubber
Hevea brasiliensis produced in Brazil in the early 20th century. As it is basically spherical primary product and exported from Brazil's Barra Port, it is called Barra rubber or Barra rubber ball
2.1.2.3.3
Eucommia ulmoides rubber
Chinese Gutta percha rubber
hard natural rubber, consisting of trans-1,4-polyisoprene, obtained from Eucommia ulmoides of the Sapotaceae family native to the south China. As its properties are similar to those of Gutta percha rubber, it is also called Chinese Gutta percha rubber
2.1.2.3.4
Gutta percha rubber
hard thermoplastic substance, largely consisting of trans-1,4-polyisoprene, obtained from Gutta percha rubber tree of the Sapotaceae family native to the Southeast Asia
Foreword i
1 Scope
2 Category and source of rubber
3 Properties and early preservation of latex
4 Commercial latex
5 Production technology and device of commercial latex
6 Classification and types of raw rubber
7 Production device of raw rubber
8 Application of raw rubber
9 Latex products
10 Special and modified rubber
11 Scrap
12 Physical and chemical properties of rubber and products
13 Compounding ingredients
Annex A (Informative) Parts of terms deleted for this standard compared with GB/T 14795-1993
Bibliography
Index of Chinese phonetic alphabet
Index of corresponding English words
