Soy Wax Polymorphism, Version 2

Polymorphism is a complicated subject, so we’ve written more than one support paper on the subject to help our soy wax customers understand it. You can view the first polymorphism paper here.

What does polymorphic mean?

Polymorphism refers to any tendency and desire of soy wax to form more than one crystal structure when it cools from a molten form to a solid candle according to the environment it is in. Not only can more than one type of crystal form in the candle, but the existing crystals can continue to change over time seeking what they consider to be a more stable structure for the environment they “live” in. In the worst cases we see this as “bloom” (white frosting), the cauliflower effect/brainy look, or just plain ugly white lumpy growths.

Conditions that can have an effect on crystal growth

Conditions that can affect crystal growth are numerous, such as: pour temperature, cooling room temperature, humidity, candle storage temperature, fragrance, dye, anything added to the wax, and of course wax composition, to name a few. The crystals are especially sensitive to temperature changes. In fact, the period from when the first crystal forms in the molten wax to when the candle solidifies is most critical. Even temperature during this time is necessary to encourage proper crystal growth. Candles made with EcoSoya container waxes are best cooled at temperatures of about 68°F to 80°F.

Understanding polymorphism in candle making

Imagine your pour temperature is 175°F but the cooling room temperature is 50°F. If you check temperature near the glass wall of the container, the wax is much cooler there than in the center by the wick. This large temperature difference is tough on the candle, encouraging different crystal growth both when the candle is setting up and when the candle burns.

One type of crystal wants to grow at one temperature while another type wants to grow at another temperature. The food industry has had the luxury of being able to dictate the environment their products are exposed to. Items such as chocolate are shipped in temperature controlled trucks to maintain their crystal structures, a luxury we in the candle industry don’t have.

The huge challenge is to control crystal growth and guide it to the form best for candles and keep it there — not an easy task. It’s a task that we at NGI have done extensive research on since 1992, resulting in the development of our CB-Advanced Soy and CB-XceL for container candles. We have compounded them to have an extremely stable crystal structure that we have blueprinted into the wax. This has resulted in waxes that are extremely resistant to frosting, cauliflowering and have an even, smooth burn pool.

If you haven’t tried CB-Advanced Soy Wax lately, Give it a try. We think you’ll be pleasantly surprised.