In the production process of silicone products, when the silicone products with lower hardness are molded, if the control is not good, there will be a phenomenon of cracks at the edge, commonly known as silicone product burst. Why do low-strength silicone products exhibit this kind of bursting phenomenon?
1. When low-hardness silicone products (30 degrees or so) are molded, they are easily affected by mold temperature and other factors, such as air bubbles (bag wind), etc. If the silicone products require body color or translucent color, it is very easy. Many small white spots are formed inside the silicone product.
2. Appropriate to improve the mold temperature later, the bubbles (including wind) and white spots of the adverse problems have been solved, but the edge of the silicone products began to appear fragmentation, which is the phenomenon of explosive silicone products. In such a situation, a bad cycle is completely formed. The mold temperature rises to burst the edge, and when the mold temperature decreases, bubbles (enveloping) and white spots occur.
3. silicone molding mold self-dismantling knife edge, too sharp or burr is the cause of the explosive side.
Explosion of silicone products easy to appear in the hardness of 30 to 50 degrees, more than 50 degrees of this appearance is not common. Understand the reasons for the low-hardness silicone products explosion edge, then in production in the face of this situation, we must promptly prevent and repair, and thus ensure high-quality silicone products, the method below:
1.low-hardness silicone products in the production, the appropriate molding temperature to reduce molding, if there is a bubble and white spots, then use the method to extend the curing time to solve. The molding temperature must drop suddenly until the silicone product does not blow up, and you can't think of the mold temperature that will fall forty-five degrees.
2. silica gel products in the production process and the number of exhaust must be controlled just right. The number of exhausts should be as small as possible, and exhaust procedures should be minimized.
3. The appropriate reduction of the amount of vulcanizing agent is also a method of avoiding bursting.
4. mold edge is too sharp, need to pull the exhaust slot, not trapped.
Low-hardness silicone products are difficult to grasp during production, and each process and process must be carefully observed to avoid mistakes resulting in defective products.