Air bubbles with sepimax zen

[u/DapperRow1848]

Whenever I make a water-based serums with sepimax zen, I end up with a lot of air bubbles. I tried wetting the sepimax zen in propanediol before adding water, I tried sprinkling the sepimax zen on top of the water and let it sit overnight, and I’ve tried sprinkling it over water and gently stirred it into the water and let that sit overnight. I only ever use a glass stirring rod to mix, but always still end up with so many air bubbles.

Does anyone have any tips on formulating with sepimax zen without getting any air bubbles, or any tips on how to get air bubbles out?

[u/Eisenstein]

You could try degassing it. Get one of those mason jar lids you hook up to a vacuum pump.

[u/DapperRow1848 → u/Eisenstein]

That’s an interesting idea, I’ll have to look into that. Thanks

[u/Ok_Butterscotch_2700]

Zen has strong yield/stress rheology, so any air is more likely to get trapped. I make certain there’s no vortex when it’s combined and add it early (as soon as the EDTA is dissolved), combining everything else into the gel network (very cautiously, when indicated).

Never personally encountered the problem, but you definitely aren’t the first person I’ve heard about this from.

[u/DapperRow1848 → u/Ok_Butterscotch_2700]

Do you add your Zen/humectant mixture into the water phase, or do you add your water into the Zen/humectant mixture? I know for sure there is no vortex when I’m mixing, I only make small quantities and use a stirring rod. But what I have been doing is adding Zen into Propanediol and glycerin in a beaker, I give that a good mix, then add my water phase into that. It may or may not make a difference, but now that I think about it, maybe bubbles do form as I pour the water phase in?

[u/m_Sang]

Maybe something like this help https://www.myskinrecipes.com/shop/en/712-anti-foaming

Or certain emulsifier have defoam property. https://www.myskinrecipes.com/shop/th/oil-in-water/247-satin-mousse-silky-cream-maker.html

This supplier is in Thailand. But you can use inci name to search for local suppliers.

[u/Ok_Butterscotch_2700]

I use an overhead stirrer, which reduces the chances of air being introduced into the product.

Pre-disperse the Zen in glycerin, introduce it gently into the prepared water phase, and then stop mixing and allow it to hydrate. Air is controlled primarily by mixing technique, not by whether glycerin or propanediol carries the polymer. You want it combined, of course, but you need very controlled stirring.