Concentrol is a company devoted to the manufacture of chemical solutions designed to intervene in various processes of the production chain. The company’s R&D team always works to achieve the best degree of efficiency in the manufacturing process of the solutions, as well as to seek the maximum degree of sustainability in terms of emissions. Concentrol’s products focus on the international industrial market, in which we always try to satisfy customers with solutions designed exclusively for their needs.

In this article, which is the continuation of: Silicone surfactants for polyurethane systems in footwear – Part 1, we will delve into the characteristics and properties of Concentrol’s product lines with respect to silicone surfactants for PU systems for shoe soles and integral type foam.

Each of the options offered by Concentrol has certain characteristics thanks to their accurate composition. The most prominent lines are:


It is designed for the formulation of integral polyurethane foam and for footwear, and is suitable for both polyester and polyether systems. It has a high stabilizing power and can be used in medium density PU systems.

This product allows obtaining a fine and uniform cell structure, closed cell, and it should be noted that it has good emulsifying characteristics thanks to its high polarity.

  • CONCENTROL STB PU-2246 and STB PU-2253

They are designed for footwear and integral systems of polyether type. They have a high stabilizing power and can be used in medium-high density PU systems.

These two lines behave as powerful cell regulators, achieving a high percentage of cells and allow obtaining foam with a uniform and fine final cell structure. One of their main features is that they increase the tensile strength and therefore have good Ross-flex properties.

  • CONCENTROL STB PU-2103 and STB PU-2104

Two products designed for shoe systems and integral foam based on polyether and polyester base with low-medium density. They have a medium stabilizing power, and also provide a medium degree of cell opening. They allow obtaining PU foam with a good surface appearance, and both surfactants are considered low-emissions.

These used as co-surfactants offer improvements in the area of ​​surface appearance of the foam and also offer a degree of cell opening that is appropriate when formulating low-density PU systems.


They are suitable to be used in integral PU systems of polyether type. They have a low stabilizing power, a medium cell opening and achieve a good surface appearance. They are stabilizers suitable for low-density systems and have a very low volatile emission profile.

These two products act as cell regulators, and their use reduces the appearance of pinholes and improves the surface appearance of the final foam. It should be noted that they help to obtain a very good cellular structure of the skin.


Suitable for PU systems for footwear. It has a medium stabilizing power and allows obtaining foams with a certain degree of cell opening. It is suitable for low-medium density systems. With its use, foams with an excellent surface appearance are obtained.

This product line is mostly used as a co-surfactant, offering extraordinary skin formation, as it minimizes the peeling effect and other defects such as flow marks or craters.

  • CONCENTROL STB PU-3160, STB PU-2290 C and STB PU-2291

These three are designed for footwear and integral systems of polyether type. They have a high stabilizing power and offer a medium degree of cell opening. They are surfactants suitable for low-medium density PU foams and, with their use, the surface appearance of the foam is very good.

These medium-regulating silicone stabilizers have the ability to improve the surface appearance and reduce imperfections such as pinholes.


It is designed for polyester type shoe systems. This product is used as a cell-opening additive and does not provide a stabilizing effect on the system. It is suitable for low-medium density systems. It provides an excellent surface appearance of the PU garment and has a very low amount of volatile emissions.

It is a regulating and cell-opening additive. It is formulated with organic polymers and is silicone free. The peculiarity of this product is that it improves the formation of the skin as more homogeneous foams are obtained, the pigments are better distributed and fewer defects by flow lines are observed.


Formulated for PU systems for polyester type shoe soles. It has a low stabilizing power and provides a medium degree of cell opening. The product is suitable for low-medium density foams, and their use provides an excellent surface appearance.

It is a regulating and cell-opening additive. This fluid has very low polarity and, therefore, it provides characteristics of flexibility, lubricity and hydrophobicity in polyurethane coatings. It is often used in high-density formulations such as filters.


It is made for PU systems for shoe soles. It has a low stabilizing power and offers a medium degree of cell opening. Suitable for low-medium density PU foams. It provides an unsurpassed surface appearance of foam.

The use of this product provides good skin formation and little flaking. In addition, it also reduces pore formation and improves mechanical properties.

For Concentrol’s team of professionals, it has always been very important to have many product lines facing different sectors, as it covers an extensive international market with very specific peculiarities. Thanks to the wide range of products they have, they can therefore offer the right solutions for every professional need.

If you are interested in any of our solutions or would like to suggest that we take care of them exclusively for your needs, do not hesitate to contact us.


Author: Josep Nadal – Technical Manager