If you have a silicone mold you want to coat with epoxy resin, there are some things you should know before getting started. Epoxy resin can be used on silicone if it is done correctly.
But if not, your project could end up in the trash.
Here’s what you need to know about using epoxy resin on silicone molds and other projects using silicone and epoxy resin together.
Can I epoxy over silicone?
The short answer: yes. In fact, one of the most common uses of epoxy is to seal cracks in concrete slabs and floors.
But there are a few steps you need to take before starting your project:
First, clean up any silicone residue or dirt from the surface of the area you’re working with. You can use isopropyl alcohol or a scraper to make sure it’s clean and dry.
Next, apply a thin layer of epoxy onto that surface, ensuring that the silicone is completely covered. Then wait for about 30 minutes before putting down another layer of epoxy.
And finally, you can begin using your epoxy coating over the silicone!
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Does resin work on silicone?
Yes! Polyester resin can be applied to silicone without any issues. It’s actually quite a common practice to use silicone to make molds for casting polyester resin. Silicone is flexible, easy-to-use, and reusable, making it the best choice for molding epoxy resin parts.
If you want to make a one-piece mold of an object, silicone putty is a great choice. It comes in two parts which are kneaded together and then pressed onto the object to be molded.
Once cured (cured time varies depending on size) the piece can be removed from the mold and the leftover clay can be reused or discarded.
What does epoxy resin react with?
Epoxy resin is a thermoset polymer, which means that it does not melt once cured. This makes epoxy an ideal material to use over silicone because they do not react with each other.
The thing you have to be careful of when using epoxy over silicone is your tooling or release agent. If you use too much of either, the cure time can be extended and the epoxy might bond with the tooling or release agent instead of the surface you actually want it to bond to.
How do you resin over silicone?
To avoid a reaction between silicon and epoxy resin, you should clean the silicone surface before applying your epoxy. Make sure that it is completely dry, then sand it down to remove any imperfections.
You can also use an alcohol wipe to clean the surface before applying a primer coat of epoxy. Use a heat gun to eliminate any bubbles from forming on the surface by using quick bursts over the surface area until they dissipate.
What is difference between epoxy and silicone?
Epoxy and silicone are both adhesive compounds and they are frequently used in mold making. They differ in their properties, and when it comes to adhesiveness, silicone is better than epoxy.
While silicones have high flexibility, epoxy is rigid. Silicone cures at room temperature while epoxy needs heat to speed up the curing process.
Both compounds have strong bonding strength with the materials that they come into contact. Epoxies are resistant to chemical reactions but silicones can react with paint, plasticizers, mineral oil, and several other chemicals
Silicone has poor adhesion on non-porous surfaces like glass or metal with a very precise surface finish such as chrome or stainless steel.
What can stick to silicone?
Silicone is a great material for sealing, waterproofing, and insulating. It is a polymer that is made of silicon, oxygen, carbon, and hydrogen. You can shape it into different forms or molds to suit your needs.
However, one of the most frustrating things about the use of silicone is trying to stick something to it. This can be very challenging because silicone does not adhere easily to anything but itself or glass.
Can you epoxy over SikaFlex?
Can you epoxy over SikaFlex?
Since SikaFlex is a polyurethane sealant, not silicone, it will not react with epoxy. You can epoxy over this product at any time.
What sticks to cured epoxy resin?
Epoxy resin is a waterproof coating that is used to protect your surface from scratches and water damage. Generally, it can be stuck onto anything, whether wet or dry, though some materials may require additional prep work.
Conclusion
To answer the question of “can you put epoxy resin over silicone”, yes you can. Silicone is not porous and does not accept epoxy resin. It is also difficult to paint with acrylic paints when using silicone for your project.
Epoxy resin can be used as a sealant for silicone if the silicone has been properly prepared first. Always test any material prior to starting a project to ensure compatibility with your epoxy resin mix.
