| Thinking of non stick coatings with silicone? But, then | | | | coherent. And that involves choosing products that are |
| thoughts of 'non-permanent', migratory, even messy | | | | curable, cross-linkable. |
| compounds come to mind? | | | | Today, silicone coatings are often integrated with |
| Well, it's certainly understandable. After all, silicone, as a | | | | resin-fillers. This results in greater density, more |
| temporary release agent, can transfer in measurable | | | | cohesive strength. Imagine a 'stretching' phenomenon |
| amounts to the released surface. No different than | | | | at the sticking interface. Here, the silicone compounds |
| soaps, oils -- or fluorocarbons! Their effectiveness, you | | | | are now stiffer, comparatively inelastic surfaces with |
| see, comes from weak boundaries formed between | | | | better energy absorbing capability. |
| the two surfaces. The result: surface contamination! | | | | Translation: A non-migratory coating with sustainable, |
| But it doesn't have to be that way. New formulations | | | | high release. |
| of silicone abound. Many in fact are proving to be | | | | For applications requiring release from pressure |
| surface free from migratory species. | | | | sensitive adhesives, these newer formulations of |
| Polydimethylsiloxanes (PDMS for short) are an | | | | silicone are ideal. So, packaging equipment designers |
| excellent example. Low surface energy comes from | | | | and manufacturers take note! |
| the dimethyl surface to the air. (A convenient measure | | | | Today, custom coaters take these products a step |
| for this is surface tension, about 20-22 dynes/cm.) | | | | further. Using 'external' forms of reinforcement such as |
| Coupled with a highly flexible, unhindered polymeric | | | | plasma spray, their abrasion resistance--a term |
| chain or backbone (Si-O-Si bonds) unlike Teflon, makes | | | | completely uncharacteristic of silicone--is now a reality. |
| silicone release coatings unbeatable. | | | | So, yes, silicone non stick coatings will continue to |
| But, for silicone to be non-migratory, its film must be | | | | emerge, and evolve. |