A few concepts about rubber
1, the concept of rubber
Rubber: The world's common definition of rubber is quoted from the American national standard ASTM-D1566 (America Society of Test and Material). The definition is as follows:
Rubber is a material that can be modified (vulcanized) by its ability to recover its deformation quickly and vigorously under large deformations. Modified rubber is substantially insoluble (but soluble in) boiling solvents such as benzene, methyl ethyl ketone, and ethanol-toluene mixtures. Modified rubber is stretched to twice its original length at room temperature (18~29℃) and held for one minute, and after removing the external force, it can recover to less than 1.5 times its original length within one minute, and the material with the above characteristics is called rubber.
Notes:
(1) Rubber is a material with specific use and processing properties, is an organic polymer material.
2) Rubber is highly elastic at room temperature.
3) Rubber can be modified in the sense that it can be vulcanized.
(4) Modified rubber, i.e. vulcanized rubber, does not dissolve but can dissolve.
2, the concept of raw rubber
Raw rubber: Rubber to which no cooperating agent has been added and which has not yet been cross-linked.
It is generally composed of linear macromolecules or linear macromolecules with branched chains, and can be soluble in organic solvents.
3, the concept of rubber mixing
Mixed rubber: Raw rubber and cooperating agent are processed and mixed evenly and not cross-linked rubber.
Commonly used cooperating agents include vulcanizing agents, accelerators, active agents, reinforcing fillers, antioxidants and so on.
4、The concept of vulcanized rubber
Vulcanization: Rubber obtained by cross-linking the linear macromolecules into a three-dimensional mesh structure under the action of certain temperature, pressure and time. Generally insoluble in solvents.