Vulcanization Process
Chemical vulcanization system employed primarily for fluoroelastomer polymers to achieve specific physical properties. Utilizing a bisphenol cure allows for the production of seals with high resistance to compression set and heat. This mechanism relies on an ionic reaction rather than a free radical path.
It provides a balance of processing safety and end product durability.
Molecular Architecture
Reaction sites on the polymer chain respond to the presence of an accelerator and a dihydroxy crosslinking agent. This bond formation creates a stable network that resists deformation under mechanical load. Controlling the ratio of these chemicals dictates the final hardness and modulus of the elastomer.
Heat Resistance
Elastomers treated with this system maintain their integrity at temperatures exceeding two hundred degrees Celsius. Minimal outgassing and high steam resistance make the resulting compounds suitable for semiconductor and pharmaceutical environments. The vulcanized structure remains stable against many aggressive fuels and chemicals.
Reactive Limitation
Moisture levels in the raw material or the mixing environment can interfere with the ionic bond formation. Incomplete vulcanization leads to a reduction in tensile strength and a marked increase in permanent set. Strict adherence to the cure cycle timing is required to prevent scorching or undercuring.
The system is generally less effective for polymers requiring high acid resistance. Surface finish can also be affected by the specific accelerators used in the compound.
