In a strict sense, mixing silicone rubber does not need to be refined again. It only needs to be stored in a cool, dry and ventilated place. If it needs to be produced, it can be produced by adding sulfur and color. Therefore, mixing silicone rubber raw rubber generally does not need to be refined again. On the contrary, if the mixed silicone rubber is not put into production for the first time after adding the color of vulcanizing agent, it needs to be re refined. How long does the sulfur and color mixed silicone rubber need to be re refined after storage?

Generally, the mixed silicone rubber with sulfur and color is used immediately. Its effect and quality are the best. If it needs to be stored, it should be stored in a cool and dry place as far as possible. If conditions permit, it can be stored in the refrigerator. Generally, vulcanizing agent volatilization will occur in the mixed silicone rubber with sulfur and color according to seasonal changes. The hotter the weather is, the higher the temperature is, the faster the vulcanizing agent volatilizes. Generally, the mixed silicone rubber (sulfur and color) can be effectively preserved for about 15 days in summer, about 30 days in spring and autumn, and about 60 days in winter. If the shelf life is exceeded, it needs to be refined again and the vulcanizing agent can be added again.

In addition, we can also decide whether to return the mixed silicone rubber according to its vulcanization performance. If the vulcanization performance is poor and the product is scrapped, we will return the mixed silicone rubber again even if it has not reached the shelf life.

Mixed silicone rubber can be re refined after adding most vulcanizing agents, but for individual models of vulcanizing agents, if they exceed the shelf life, the materials will be completely scrapped. For example, the effective storage period of platinum curing agent added into the mixed silicone rubber is only 8 hours. If it exceeds the time limit or the storage temperature is too high, it will lead to the curing of the mixed silicone rubber itself, which is of no help even through secondary rubber mixing.

Generally speaking, if the storage period of sulfur and color mixed silicone rubber exceeds, we can re add vulcanizing agent on the open mixer. However, it should be noted that the degree of adding vulcanizing agent in the secondary vulcanization needs to be determined according to the long storage time of the material. Generally, the proportion of adding vulcanizing agent in the secondary vulcanization is less than that in the first time.