Match chemistry

The chemistry of manufacturing modern matches has gone through interesting stages of its development. And it all began when the cutting of sparks when a stone struck a piece of pyrite FeS2 and burning them with charred pieces of wood or plant fibers was almost the only way to get fire by a person.

The first matches, based on chemical reactions, began to be made in the late 18th century

The first matches, based on chemical reactions, began to be made in the late 18th century. In the beginning, these were wood larvae, on the tip of which, in the form of a head, potassium chlorate (the Berlotte salt KCl3) and sulfur were fixed. The head was immersed in sulfuric acid, a flash occurred, and the ray ignited.

The most important stage in the development of chemistry on the way to modern matches was the introduction into the mass of the match head white phosphorus (1833). Such matches were easily ignited by rubbing against a rough surface. However, when burning, they created an unpleasant smell and, most importantly, their production was very harmful for workers. Pairs of white phosphorus led to a severe disease - phosphoric necrosis of bones.

In 1847 it was established that white phosphorus when heated in a closed vessel without air access turns into another modification - red phosphorus. It is much less volatile and almost non-toxic. Soon, white phosphorus in the match heads was replaced by red. Such matches were ignited only when rubbing against a special surface of red phosphorus, glue and other substances.

There are several varieties of modern matches. By appointment, matches are distinguished, which are ignited under normal conditions, water-resistant (designed for ignition after storage in wet conditions), wind (ignited in the wind), etc.

When the match is burned, it is necessary, for safety reasons, to get the non-radiant coal from the straw and keep the red-hot slag from the burnt head on it. To eliminate the smoldering of straws and fixing the slag from the head, the straw is impregnated with substances that form a film on its surface during combustion. Due to this film, the combustion of coal ceases. It also fixes the slag from the head of the match. As antifoams, phosphoric acid and its salt (NH4)2HPO4 are used.

To ensure an effective transition of the flame from the head to the straw, the latter near the head is impregnated with molten paraffin. Paraffin is easily ignited by burning the head and gives a bright flame, which is important when using a match as a light source. In addition, it is safe when storing matches, does not emit smoke, smoke or harmful gases when burning.

Over a period of more than 150 years, the chemistry of the head of the match has a large number of formulations of incendiary masses. They are complex multicomponent systems. They include: oxidants (KClO3, K2Cr2O7, MnO2), giving the oxygen needed for combustion; combustible substances (sulfur, animal and plant adhesives, phosphorus sulphide P4S3); fillers are substances preventing the explosive nature of the combustion of the head (crushed glass, Fe2O3); gluing substances (glues), which are also combustible; acidity stabilizers (ZnO, CaCO3, etc.); substances that color the matchbox in a certain color (organic and inorganic dyes).

The burning temperature of match heads reaches 15000 C, and their ignition temperature lies in the range 180-2000 .

Phosphoric (terio) mass is also multicomponent. It is applied to the narrow side outer sides of the match box. The composition of the most common grated mass includes: red phosphorus, antimony sulphide (3) Sb2S3, iron rusher Fe2O3, pyrolusite MnO2, chalk CaCO3, glue.

It should be noted that the reaction occurring during the combustion of the match head is one of the most violent and dangerous chemical processes. Therefore, the treatment of matches requires respect.