Punto de Fusión
August 17, 2020
Dear Dr. Vela:
Which type of wax is better, a vegetable (hydrogenated fat) or a synthetic wax?
It all depends on the type of candle you are making or the type you would like to make.
If your purpose is to replace a petroleum paraffin without having to make many changes to your formulation and process, then synthetic waxes are more appropriate.
As we discussed previously, synthetic waxes are comparable to paraffin, Fischer Tropsch waxes have the same structure and, in most cases, over 90% of the time they can replace petroleum paraffin, without having to make adjustments in your formula; especially in the way they burn.
Alpha Olefins are more complex. They will not have major effects when it comes to scented and colored candles, but the burning may be different; since they are modified carbon chains. A lot depends on the refinery used.
Synthetic waxes are very consistent just like paraffin.
Given their triglyceride chain structure instead of a hydrocarbon; vegetable waxes / hydrogenated fats (soy, palm, coconut) or animal fat (tallow) are very different products. The paraffins and synthetic waxes that we normally use at a melting point of 54-60 C, have most of their carbon chains between C 22 and C 30, while hydrogenated fats have the peak at C 16. We can call them waxes because it is a saturated fat with hydrogens that in conjunction with the natural stearin in each product allows them to be solid at room temperature.
Hydrogenated fats are polar products, while paraffin is not. This will affect the type of fragrance you can use and the compatibility and dispersion of colors. The crystalline structure is not the same and therefore the appearance of the candle will not be the same. Finally, the viscosity is much higher, and this affects the burning of the candle, so you will have to adjust your wick according to the product you are using.
Therefore, the most comparable wax to paraffin would be as follows:
1- GTL or Fischer Tropsch synthetic waxes.
2- Alpha Olefins
3- Hydrogenated fats.