Secondary vulcanization is an important process in the production of silicone rubber products. Secondary vulcanization:
① It can remove the peculiar smell of vulcanizing agent and various additives added in silicone rubber products;
② . It can reduce the size of silicone rubber products. The size of products without secondary vulcanization is not stable;
③ It can stabilize the physical properties of silicone rubber products, and greatly improve the density, tensile strength, resilience, hardness, swelling degree, density and thermal stability of its structure.

However, some problems may occur in the secondary vulcanization of silicone rubber products. What are the causes of the problems? How can we solve it?
1、 Cracking and blistering
Cause: Volatile matter is discharged too quickly or air is hidden inside the shaped vulcanized products.
resolvent:
① Adjust the conditions of gradual temperature rise to slow down the temperature rise rate;
② Check the recycled rubber and remove air bubbles.

2、 Large compression deformation
Cause:
① Insufficient vulcanization;
② Improper selection of rubber formula.
resolvent:
① Put it into the oven to prolong the curing time;
② Increase air circulation;
③ Reduce the quantity of products put in;
④ Check the oven temperature;
⑤ Select the rubber with small compression deformation.

3、 Too high hardness
Cause: Excessive heating and vulcanization in the oven
resolvent:
① Check the temperature of each part of the oven;
② Check and inspect the temperature control system.

4、 Too low hardness
Cause: Volatile gas is not completely removed from the oven
resolvent:
① Check the ventilation of the oven;
② Check the oven temperature;
③ Reduce the quantity of products put in;

5、 The hair is sticky with black spots
Cause: Partial concentration of volatile gas degrades silicone rubber
resolvent:
① Slow down the heating rate and discharge volatile matter in time;
② Check the air flow;
③ Prolong the curing time and fully eliminate volatile gas.