How to make indicators from explosives derivatives that can save people's livesTextile indicators have been invented in Russia that change color at high concentrations of acid or alkaline vapors in the air.
They contain dyes created from TNT derivatives during its disposal. Such sensors can be used in the manufacture of workwear and personal protective equipment to prevent chemical burns. Industry experts consider the development promising, but additional tests are needed.
Simple and effective
An unusual type of sensors for the prevention of danger in chemical industries was created at the Russian State University named after A.N. Kosygin. They contain substances that have halochromic properties — that is, they are able to change color when the pH level (an indicator of the acidity of the environment) increases or decreases.
Analyzers are made of textile or film materials and can be integrated into workwear. Such simple devices, according to scientists, are able to become reliable assistants-controllers in chemical production and prevent injuries associated with burns that occur when workers come into contact with dangerous reagents. For example, they will warn when an increased concentration of acid or alkaline vapors has formed in the workshop or laboratory. This will give people the opportunity to take measures and prevent a threat to life and health.
Photo: A.N. Kosygin Russian State University
Image source: iz.ru
Halochromic substances can also be included in the composition of the protective layer covering, for example, the working surface of household gloves. If the wearer touches the container from which the reagent leaked, the information about this will immediately be reflected on the glove in the form of a contrasting color change of the polymer coating.
— A person reacts to a color change faster than to other danger signals. This is how our subconscious works. Therefore, we believe that chromo sensors are useful as a means of rapid indication. In this sense, they will be an important addition to the monitoring and notification tools that are already available at chemical industry enterprises," Dmitry Kuznetsov, project manager, head of the Department of Organic Chemistry at the Institute of Chemical Technologies and Industrial Ecology of the Kosygin Russian State University, told Izvestia.
Red on Yellow
According to the scientist, the task of the specialists was to create dyes that would predictably change color only based on the pH level. At the same time, they must be independent of other factors, such as sunlight, temperature changes or mechanical influences. It is also important that they can be washed, kneaded, ironed without losing their main function.
— The advantages of chromo sensors are that they are constantly near the employee, in the viewing area, visible to the naked eye, which allows for better control of the situation. At the same time, they do not require energy sources," Dmitry Kuznetsov explained.
Photo: A.N. Kosygin Russian State University
Image source: iz.ru
Currently, the analyzers are able to change color in the range from yellow to maroon. According to scientists, other combinations are not excluded. For example, the colors of the danger signal can be rich green or dark purple.
Dual purpose
Interestingly, the basis for halochrome paints are compounds that are made from trinitrotoluene, also known as TNT. It is used all over the world as an explosive. The problem is that during long-term storage, it becomes unstable and can detonate. Therefore, when its safe storage period expires, disposal is required.
Previously, the explosion method was used for this. Subsequently, chemists proposed ways to transform TNT into peaceful products. In particular, at the Kosygin Russian State University, it is processed into semi-finished products, from which dyes are obtained.
— The cost of such materials is much lower than that of analogues. In addition, they have a number of useful properties. For example, they prevent the formation of moldy fungi on the painted surface. Unfortunately, Russian enterprises are tied to imported dyeing and finishing machines. Therefore, they cannot use our materials, otherwise they will face the refusal of service providers. Faced with this, we decided to find our niche and developed smart dyes," Dmitry Kuznetsov said.
Project Manager, Head of the Department of Organic Chemistry of the Institute of Chemical Technologies and Industrial Ecology of the Kosygin Russian State University Dmitry Kuznetsov
Image source: Photo: A.N. Kosygin Russian State University
Introduction into production
In order to adapt the sensors to different types of chemical industries, scientists have created a line of indicators with a narrow pH interval. For example, one of them changes color at high acidity values, the other, on the contrary, only at low. The third is activated in an alkaline environment.
— The life and health of people will depend on the correct operation of these products. Therefore, before commissioning, it is necessary to test the sensors in any possible conditions. It may take a long time," Vladimir Tyurin, senior researcher at the Laboratory of New Physico—Chemical Problems of the Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, told Izvestia.
He also noted that the process of finalizing products will occur faster when representatives of the textile industry will clearly formulate the terms of reference for scientists.
— For the introduction of chromodetectors into the production process, it is also necessary to form a culture of their use, — says Nina Zubkova, head of Energokontract (specializing in the manufacture of workwear).
Photo: A.N. Kosygin Russian State University
Image source: iz.ru
In her opinion, it is important to create instructions, conduct events and train representatives of enterprises so that they understand what needs to be done in cases when sensors report an unfavorable situation.
Today, scientists are ready to interact with industry representatives to organize the mass production of their products and the introduction of sensors into the technological process of chemical enterprises, the Kosygin Russian State University added.
Andrey Korshunov