Microencapsulation

Microencapsulation describes a chemical process in which small parts of substances of all three states (gaseous, solid, liquid) can be provided with a shell. This results in immobilisation. Through the chemical technology, which was first used in industry in 1953, the active substance surrounds itself with the shell, resulting in the capsule. In this way, the properties of the substance can be better controlled. Reactivity, stability and solubility can be increased or decreased.

The state of the microencapsulation can be precisely controlled: The shell can be reopened and a period of time can be set by the different processes at which it falls off again by itself (diffusion). Or one decides on a process that leads to permanent encapsulation.

Application examples for microencapsulation

Many substances are now microencapsulated. Textiles are subjected to encapsulation so that they still have a tolerable odour for a long time. For facades of houses, you can (have) microcapsules generated to protect the building from weeds. Without microencapsulation, it is difficult to make the packaging of a deodorant or other cosmetics smell good. With the help of the process, however, this can be achieved. Products where raw materials that are incompatible with each other come together or need to be separated can be made or separated with the help of encapsulation. Another example is protecting substances from oxidation by depriving them of oxygen through the encapsulations. It is possible to make elements more suitable for certain applications. Food supplements and medicines are encapsulated in such a way that they release their active ingredients into the body after a fixed period of time. Side effects can be reduced. By controlling the pH value, the medicines and supplements can be designed to be more tolerable and to take effect in a specific area, e.g. in the intestine.

How does the microcapsule work and how is it generated?

The two main methods of encapsulation are core-shell encapsulation and matrix encapsulation. In core-shell encapsulation, the substance can be made to surround itself in different shells. The release of the substances can be sudden, or very slow if a breach of the shell is initiated from the outside. Matrix encapsulation works differently: Here, the shell mixes with the substance, from which the particles emerge. There are two methods for the release: Either it depends on the degradation rate of the shell, or the substances are brought to the outside by diffusion.