To extend the operating time of organic silicone, you can start from adjusting the curing agent ratio, controlling the ambient temperature, optimizing the operation method, choosing the right type of silicone, and using vacuum degassing. The following are specific instructions:
1. Adjust the curing agent ratio
Principle: The curing agent ratio directly affects the curing speed of silicone. Reducing the amount of curing agent can extend the operating time, but it should be noted that it should not be lower than the minimum effective ratio (usually 1%-1.5% of the weight of silicone), otherwise the silicone may not be completely cured or the performance may be reduced.
Method: Under the premise of ensuring the basic performance of silicone, appropriately reduce the amount of curing agent added. For example, adjust the curing agent ratio from the standard 100:2 to 100:1.5 or lower, but the optimal ratio needs to be determined through experiments.
2. Control the ambient temperature
Principle: Temperature has a significant effect on the curing speed of silicone. Lowering the ambient temperature can slow down the curing reaction and thus extend the operating time.
Method: Operate in a lower temperature environment (such as room temperature below 20°C), or use cooling equipment (such as fans, air conditioners) to reduce the temperature of the operating area. Avoid operating in high temperature or direct sunlight.
3. Optimize the operation mode
Principle: By improving the operation process and reducing the exposure time after the silicone and curing agent are mixed, the operation time can be indirectly extended.
Method:
Mix in batches: Mix the silicone and curing agent in batches to avoid excessive mixing at one time, which may cause some silicone to cure prematurely.
Quick use: Use as soon as possible after mixing to reduce the residence time of the silicone in the mixed state.
Avoid pollution: Ensure that the operating environment is clean to prevent impurities or moisture from entering the silicone and affecting the curing process.
4. Choose the right type of silicone
Principle: Different types of organic silicone have different curing characteristics and operation times. Choosing a type of silicone with a longer operation time can meet the need to extend the operation time.
Method:
Slow-drying silicone: Choose a slow-drying organic silicone designed for extended operation time.
Addition type silicone: Addition type silicone usually has a longer operation time and stable performance after curing.
5. Use vacuum degassing
Principle: Bubbles in silicone accelerate the curing reaction. Vacuum degassing can reduce the number of bubbles, thereby extending the operation time.
Method: After mixing the silicone and curing agent, use a vacuum degassing machine to remove bubbles before injecting into the mold or application area.