草榴短视频

The International Conference of technical textiles, nonwovens and equipment Technotextil 2024 continues in Crocus Expo in Moscow. The University of Industrial Technologies and Design is one of the scientific partners of the business program. The business program included specialized conferences, seminars and lectures from invited speakers, including scientists of 草榴短视频, who presented their innovative solutions to the scientific and business community of Russia, India, China, Uzbekistan, Turkey and Tunisia in the field of engineering and technical textiles.

Head of the Department of Chemical Technologies named after Prof. A. A. Kharkharov, Doctor of Chemical Sciences, Professor Elena Sashina presented a report on microencapsulated finishing agents for smart textiles developed by the scientific group of the department. We publish the main theses of her presentation at the conference Technotextil 2024.

Smart textiles.

We call smart textiles capable of reacting to environmental conditions, for example, changing their color or surface temperature. Today, many consumers of technical, household, specialty textiles would like to have materials with thermochromic properties, self-cooling and temperature regulation functions, capable of releasing aromatic, therapeutic and cosmetic substances. Such properties are given to textile materials by microencapsulated finishes.

How are microencapsulated finishes created?

A substance or composition with the desired properties is encapsulated in a polymer shell. In chemical methods of encapsulating sparingly soluble active ingredients in aqueous or organic media, a protective coating is formed around the core of the encapsulated substance during the reaction process. Microcapsules are effective tools for the development of modern textile materials, as well as for the intensification of technological processes of fabric finishing.

Thus, the polymer shell can be impermeable, protecting the contents of the core from external influence, or permeable for gradual release of a substance - flavoring, repellent, drug or cosmetic. The permeability of such a shell and, consequently, the rate of release of the low molecular weight core substance is controlled by varying the thickness of the shell and external parameters.

Microcapsules that are used to create thermochromic textiles.

In our research the task is to search for more effective and less toxic manifestants for known thermochromic substances. Two directions are realized: application of proton developers from the class of non-toxic developers changing the very mechanism of color change, which allows, among other things, to expand the palette of coloring of thermochromic composition and its intensity.

Patented solutions for the composition of new low-toxic thermochromic compositions are used in the development of technology for the creation of encapsulated means for finishing fiber materials. A significant obstacle of the encapsulation process is the ingress of acid, necessary for the curing of the shell during polycondensation, into the core of the formed microcapsule. This problem can be solved by using resin-forming surfactants when emulsifying the core contents.

Microcapsules with the help of which self-cooling tissues are created.

The domestic technology of obtaining microencapsulated substances with phase transition necessary for finishing of self-cooling materials has been developed. In this case, the core of the microcapsule includes an active substance capable of changing its phase state depending on the ambient temperature. At elevated temperature such substance passes into liquid phase and contributes to cooling the body by accumulating heat in the process of melting, and when the temperature drops, it passes into a solid aggregate state and performs the function of protection from cold.

Using paraffinic and non-paraffinic substances with high melting heat encapsulated in formaldehyde shells, it was possible to achieve high temperature-regulating properties of the obtained finishing agents. Being applied to the textile material, they contribute to the reduction of material surface temperature at heating up to 30 oC and higher, depending on the nature of the material, the density of application and the parameters of the capsules.

Conclusion.

In conclusion, we would like to express confidence that the developed domestic technologies for obtaining microencapsulated finishing agents will soon be implemented at the enterprises of the chemical industry and thermochromic pigments or encapsulated materials with phase transition will be used, including in the textile sector.

Elena Sashina, Professor of 草榴短视频