The polyurethane (PU) foam used in footwear and integral foam share many general aspects. Similar surfactants can be used in both systems. However, there are different types of silicone surfactants, as some are designed for PU systems based on polyethers (in integral PU and footwear) and others for polyesters (only in footwear PU).

In these highly stable systems, many surfactants are also used as cell regulators or openers. This type of PU foam has properties closer to rubber than traditional PU foam. Therefore, manufacturers of these two types of foam seek elastic and abrasion-resistant properties directly related to shoe soles.

Foams must withstand daily wear and tear. Some important properties sought are:

  • Ross-Flex Resistance: resistance to cracking due to continuous and rapid flexing. It is measured with a machine that produces repetitive bending movements.
  • Hardness: an intrinsic property determined by durometers. It does not have a simple relationship with fundamental properties.
  • Tensile Strength: resistance to breakage under elongation force. It is measured by cutting a loop-shaped piece and observing the breaking force.
  • Regulación celular: a small and uniform cell structure is desired, avoiding surface defects. Partial cell opening is sought in these systems, as a closed structure causes defects.

Silicone stabilizers are relevant in shaping processes and are used to enhance performance and durability. Concentrol offers solutions that adapt to each customer’s needs.


STB PU-2248

This reference stands out for excellent stabilizing power, ideal for both polyether and polyester polyurethane foams, including footwear and integral applications. It offers a fine cell structure without cell opening, improving foam appearance with emissions below 2% and average-high density. It is especially valued for its efficient emulsifying and stabilizing capabilities.


STB PU-2246 / STB PU-2253

These solutions have high stabilizing power and are particularly effective in creating a uniform and fine cell structure without cell opening, contributing to improved Ross-Flex resistance and tensile strength. They are suitable for applications requiring low emissions and maintain an average-high density.


STB PU-2103 / STB PU-2104

These references offer good stabilizing power with moderate cell opening, optimizing foam appearance. With low emissions and low-medium density, they are co-surfactants that significantly improve surface finish.


STB PU-1231 PFJ / STB PU-1234 PFJ

With a more moderate stabilizing capacity, these cell regulators offer good cell opening, reducing pinholes and improving surface appearance. With low density, they are ideal for foams with an excellent cell structure on the surface.


STB PU-2160

STB PU-2160 stands out for good stabilizing power with a wide cell opening and a notable positive impact on foam appearance. It has emissions below 2% and low-medium density, minimizing defects such as peeling.


STB PU-2290 C / STB PU-2291

These references have high stabilizing power with good cell opening, improving surface appearance and reducing pinholes. With emissions below 2% and low-medium density, they are silicone stabilizers offering moderate cell regulation with a good ability to enhance surface appearance.


STB PU-4001

A silicone-free additive offering excellent cell opening and a very positive impact on surface appearance. With low emissions and low-medium density, it improves foam homogeneity and pigment distribution.


STB PU-4002

This additive provides good cell opening and an excellent impact on surface appearance. With low-medium density and emissions below 2%, it is ideal for high-density polyurethane coatings and filters, offering flexibility and hydrophobic properties.


STB PU-4052

With good stabilizing power and good cell opening, STB PU-4052 enhances foam appearance and reduces pores. With emissions below 2% and low-medium density, it improves mechanical properties, making it ideal for foams requiring strength and durability.

In the context of constant development and innovation, Concentrol understands the importance of advancing and continuously improving its products. Research is a fundamental pillar in the company’s philosophy, allowing it not only to adapt to changing market needs but also to anticipate them.

Through relentless exploration and the application of cutting-edge technology, Concentrol is committed to offering solutions that exceed customer expectations, ensuring that each product reflects the quality, innovation, and reliability that define the brand.

Committed to creating responsible and sustainable solutions, at Concentrol, we work and innovate with chemistry to have a positive impact on society and the planet. It reflects the company’s continuous effort to develop silicone stabilizers and other solutions that not only meet high-performance standards but also promote sustainable practices.

This long-term vision not only seeks to benefit end-users with high-quality products but is also dedicated to protecting the environment, ensuring that industrial progress and ecological conservation can go hand in hand.