In base to my question about How could a dragon develop blue fire breath?, one of the most interesting solutions is that the dragon could be able to produce aerogel for resist its own fire, so why not?, aerogel have a lot of more interesting characteristics, in addition to the high temperature resistance is extremly light and resistant compared with its weight and density.
And compared with other strange biological features this looks easy to develop, with the different types of aerogel. Inorganic based on metalic oxides, organic based on carbon polymers and the two which I thought are more helpful for this question, the silica and graphite aerogels.
Currently the stingging nettle can synthetize silica spines and marine sponges use silica en their skeletons. And carbon, practically the life is based in carbon and carbon dioxide is extremely abundant.
Although it has a limit of resistance to heat, which is very high of 500-2000 ° C, if a dragon could produce this material in its body, it could regenerate it when it wears out. Thing that is useful too for other kind or fire manipulators, How would a "flaming collar" work in an animal and how could it be useful?
And apparently the raw materials are the easy part, but I don't know how aerogel is produced and how a living creature could produce it in its body, neither I know if this could be product of natural evolution or obligatory genetic engineering product.
By the way, if aerographite (aerographene) is other problem already exist a question about Could a living creature produce graphene? and I thought by myself I can solve that probkem