Fire could be the best thief in this world. This statement is not an exaggeration because it can never be caught and punished for destroying our valuable bonds, cash and papers. The best thing anyone can do to save their precious papers is to hide them from this thief. Here is an article that speaks about the materials that are used in creating these specific hideouts.
Polymers are a big boon to man in this regard. Right from the reign of early Egyptians, man has tried making composites that resist fire. The ancient composites included combinations like Gypsum and clay, Gypsum and hair, alum and vinegar, gypsum and ammonium chloride etc. Even, concrete is fire resistant to certain extent and are at the same time cheap that they are widely used.
The actual commercialisation and mass scale production of these materials began seeing the aftermaths of World War II. Fire retarding polyesters and canvas coated with halogenated paraffin and antimony oxide were used.
In general, synthesising polymers that resist fire is much difficult than to fill usual polymers with additives that resist fire. But the dedicated intrinsically fire resistant polymers are of better quality than that of fillers. Use of polar monomers of high hydrogen bonding ability and presence of many inorganic groups increase the fire resistibility of a polymer.
Linear single-stranded polymers with cyclic aromatic components are rigid and expensive but are one amongst the top materials that resist fire. Polybenzoxazoles, polybenzimidazole, polyimide are few polymers that fall under this category. Certain polymers with aromatic heterocyclic monomers form links making them look like ladders and are tougher. Any polymer that has many inorganic groups is generally fire resistant.
Well, man is never satisfied with what he has got and always seeks for something better than the ones that exist. This only means we can expect more materials to come save us.
