Shocked to the core: Antistats, Dissipate Your Processing Issues
Did your science teacher ever rub a balloon on your head and stick it on your sweater? Your teacher was trying to demonstrate static electricity. Electrostatic charges are commonly generated by frictional contact between two materials with different susceptibilities to electron loss. Static charges can accumulate on a polymer in many ways, but the lead culprit is friction, as polymers are insulative in nature. Static electricity can cause issues such as dust pick up, handling issues in packaging such as denesting or filling operations, and electrical shocks that can result in safety hazards. Antistatic additives are used to reduce or eliminate problems caused by static electricity and dissipate electrostatic charges in polyolefins.
- Colortech’s migratory antistatic additives will adsorb moisture from the atmosphere forming an electron pathway for static dissipation. This mechanism works in many applications including blown or cast film, injection molding, and blow molding. The static decay time and the surface electrical resistivity are commonly used to specify the static performance of plastic films and sheets. The performance of migratory antistats is dependent upon humidity levels. As humidity decreases, it becomes more difficult for the antistats to adsorb and hold moisture, so selecting the antistat type becomes critical.
- For this reason, Colortech also offers internal antistatic additives. Internal or non-migratory antistats form a “conductive” network inside the polymer to dissipate static charges. Internal antistats provide the same benefits as migratory antistats and may help avoid common problems encountered when using migratory antistats, such as printing or poor performance due to low humidity.
- Colortech has many options ranging from food contact applications to sensitive applications like electronics packaging. We’ve got the chemistry solution for you in a pellet.
The Laws of Attraction
Parison sway is a common processing issue for blow molders. It can occur due to misalignment of the die, but it can also be due to attracting or repelling forces due to charge build-up. This problem may lead to difficulties with the blowing step and can sometimes be eliminated with the addition of an antistat.
Static discharge is a safety hazard when working with parts that have a high charge buildup. Consumers and your employees can experience this discharge in the form of an intense “shock.” Antistats can help eliminate this issue.
Contact a Colortech Sales Representative to get a quote on the antistatic concentrate that is right for your needs. Resin selection and other additives also affect performance. Our technical service team would love to help you select the right chemistry for your application!
Technical Services Representative