What are the factors that affect the shrinkage rate of fluororubber plate products

There are many factors that affect the shrinkage rate of fluororubber plate products, including rubber material, product shape (different shrinkage rates for different parts of the same product), vulcanization temperature, and process methods. The following are several main factors:
1. Vulcanized rubber hardness The shrinkage of rubber decreases as the hardness increases, with a smaller value of 75-85 (Shore A hardness).
2. Various rubbers with different molecular structures have different effects on shrinkage. For example, when adding the same amount of reinforcing agent, the shrinkage of various vulcanizates vulcanized at different temperatures is fluororubber>silicone rubber>ethylene propylene diene monomer>styrene butadiene rubber>natural rubber>nitrile rubber>neoprene. The shrinkage of several rubbers varies at different temperatures.
3. The fillers in the filler compound also have a significant impact on the shrinkage of the vulcanizate. Especially for fillers with a large amount of filler, the shrinkage of the vulcanizate decreases with the increase of the amount. In addition, different types of fillers have different effects on the shrinkage of vulcanizates. Because the linear temperature shrinkage coefficient of the filler is small, it is close to the metal mold.
4. Curing temperature Curing temperature also has a certain impact on the shrinkage of the product. As the temperature increases, the curing shrinkage will also increase. Reducing the curing temperature appropriately can reduce the shrinkage.
5. When the framework material fluoroelastomer board product has a fabric framework, the shrinkage rate of the cotton framework is 0.2% - 0.4%, the shrinkage rate of the polyester framework product is 0.4% - 1.5%, and the shrinkage rate of the nylon framework product is 0.8% - 1.8%. The more layers, the smaller the shrinkage. The smaller the shrinkage rate of the fluoroplastic plate product embedded in the metal, the shrinkage rate of the side facing the metal is 0-0.4%, and the shrinkage rate of the fluoroplastic plate product facing the unilateral side is 0.4% - 1.0%.