"Synthetics (polyester) may catch fire quickly......sputter, flame and melt to the skin or the flaming melt will drop to the floor. Residue is molten and hot and difficult to remove." Taken from the linked article.

Polyester is petroleum based. Oil is a natural fuel for fire and highly flammable.

The article goes on to say that "polyester batting should not be used in a Baby Quilt or a quilt made especially for an Elderly or Invalid Person. The Burn Test Photos clearly show that the Flame Retardant, 100% Cotton, and 100% Wool battings were clearly the best choices for these types of quilts because they better resisted the burning process."

If any of you have seen polyester clothing catch fire and/or melt when someone was wearing it, you'd never go near the stuff. It's pretty scary. I ripped a shirt off someone that was standing in front of a wall heater and the whole back was in flames and melting. Other than the fact that I almost chocked him because I pulled from the back, he was lucky that none of the melted fabric stuck to his skin.