Aniline, as important as it is invisible

There is a chemistry that unites the sole of the sneakers we put on to run with the foam of the mattress where we sleep. Surprising, most of us will say. But what if we discovered that there is a raw material common not only to these foams and rubbers, but also to synthetic paints, herbicides, and even fibers that are highly resistant to heat and shock? It exists and is called aniline.


What is it?

From the morning run to the moment we lie down, aniline is a discreet presence, allowing for the existence of a thousand and one everyday products whose function we do not dispense with.

Shared by many indispensable assets, aniline has characteristics different from any other product, which make this raw material one of the most important chemicals in our daily lives.

Also known as aminobenzene or phenylamine, it is a substance belonging to the primary amine family - an important compound in the manufacture of dyes.

Its formula is C6H5NH2 and, in its pure state and under normal temperature and pressure conditions, it is a colorless, oily liquid. Aniline is obtained by hydrogenation of nitrobenzene and in the presence of a catalyst. It is susceptible to oxidation and, although it has no color, it darkens when exposed to air, even having a yellow or even almost red color, which anticipates its propensity for the manufacture of dyes.

Etimo Portuguese

To trace the origins of aniline we have to go back to the 19th century, when it was first isolated in 1826 by Otto Unverdorben, using the destructive distillation process of the indigo vegetable dye. Initially named Crystallin, the synthesis of aniline passed through the hands of several chemists, until 1843, when August Wilhelm von Hofmann demonstrated that it was the same substance, henceforth known as aniline.

Curiously, the etymology of this name, attributed by Carl Fritzsche, one of the multiple “discoverers” of aniline, takes us to Portugal, where the word anil comes from and which refers to the plant also known as indigo, from the Indigofera suffruticosa family.

The first steps in integrating aniline into the chemical industry took place in 1856, when William Perkin, a student of von Hofmann, discovered purple aniline while trying to synthesize quinine, opening the door for other aniline-derived dyes to be discovered.

From jeans to bulletproof vests

The basis for the presence of aniline in numerous products lies in the transformation into Methylene Diphenyl Diisocyanate (MDI), which since the 80s has promoted the integration of aniline as an essential substance for the comfort of modern life.

It is with the use of this compound that rigid polyurethane foam is produced, used in the manufacture of rubber, and then applied to shoe soles, tires and steering wheels of cars, to the foam of mattresses and to the insulation of buildings and cooling systems.

In the agricultural industry, aniline is used in the manufacture of herbicides and fungicides, essential for the control of pests and weeds. It also allows the manufacture of synthetic inks, such as indigo, applied to the coloring of jeans, as well as to the production of photographic reagents and stabilizers for the latex industry.

No less relevant is the use of aniline in the manufacture of aramid fibers, which are lightweight products that are highly resistant to heat and shock. These products are the ones chosen by fire departments and also by military and police forces (such as bulletproof vests) for the most risky interventions.

Portugal on the front line

Bondalti, the largest Portuguese chemical company, is the leader in sales of aniline in Europe and one of the world's largest non-integrated producers of this compound.

Production using proprietary technology, resulting in high quality of the final product, is internationally recognized and the motto of exporting to many geographies.

The company supplies aniline through pipelines, always complying with the most demanding environmental and safety standards.

In Portugal, the Bondalti plant accounts for about 3% of the world's installed aniline capacity.

The chemicals that Bondalti produces in its industrial units have a wide field of application, which extends far beyond the manufacture of rubbers and foams. About aniline, an indisputable truth - it is an essential asset for our daily lives.

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