Many customers email me to ask what kind of wax can be used in the molds. Many candlemakers are making the switch to soy wax or a soy combination wax. When you use straight soy wax in silicone the soy may break when you pop the wax out or the soy creation may look very dry.
When I use straight soy I put the mold with the soy wax into the fridge and wait for it to get cold. That usually helps the soy wax to pop out easier. Also, to help prevent the dry look I would squirt some canola cooking spray into the silicone mold. This helps the soy wax look shinier. The canola spray is also good for the silicone mold. It prevents the silicone from getting brittle.
*NOTE* Do not use any type of silicone base demolding spray in the molds. Silicone sticks to silicone and will completely destroy your mold.
I test my molds on 70 soy:30 parafin both container wax mix. I feel that having both soft waxes and the final product demolds right then the mold is good. When using this combination I do not have to use the any canola spray in the mold. The parafin wax provides the lubricant that prevents soy wax dryness.
I have encountered people that use vastly different waxes and may have some problems, but with experimentation silicone molds work wonders.