Mixing Butanol and Water to make insulator for antenna

Hi very body.

Butanol has Epsilon =9.9 and Water has epsilon = 78 (25 degree Celcius), as my measured results.

I want to make insulator with epsilon = 10, 20, 42 for my in-body antenna. My ideal is to mix Butanol and Water.

To facilitate experiments, I should make Gel for this solution. So I need to boil solution of Butanol and Water (added a small amount of Agarose).

My question is that should I boil Butanol and Water? Is this toxic?
Is there other way to make insulator with Epsilon= 10, 20, 42?

Many thanks