{"id":130772,"date":"2021-07-15T12:10:19","date_gmt":"2021-07-15T10:10:19","guid":{"rendered":"https:\/\/concentrol.com\/evolution-of-silicone-surfactants-for-high-resilience-hr-flexible-polyurethane-foam\/"},"modified":"2025-07-23T14:15:50","modified_gmt":"2025-07-23T12:15:50","slug":"evolution-of-silicone-surfactants-for-high-resilience-hr-flexible-polyurethane-foam","status":"publish","type":"post","link":"https:\/\/hosting175685eu-cp704.wordpresstemporal.com\/de\/evolution-of-silicone-surfactants-for-high-resilience-hr-flexible-polyurethane-foam\/","title":{"rendered":"Evolution of silicone surfactants for high resilience (HR) flexible polyurethane foam"},"content":{"rendered":"

[vc_row][vc_column][vc_column_text]Silicone surfactants are copolymers formed by a silicone base (apolar part) and polyethers (polar part), usually polyethylene oxide (OE) chains and polypropylene oxide (OP) chains. OE, OP and silicone content significantly affect the function of surfactants. Also the substituent at the terminal position of the polyether (R) can influence the properties of the surfactant. Therefore, you can also influence the final properties of PU foam by playing only with the surfactant, thus meeting the different needs for different applications that we can find on the market, such as flexible foams, HR foams, rigid foams, among others.<\/span><\/p>\n

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Purpose of these additives<\/b><\/p>\n

Surfactants act as surface tension depressants by reducing the pressure differences between bubbles of different sizes formed and therefore a better stability of the bubbles and a small average cell size are obtained. Therefore, surfactants condition the formation of fine cells, thick cells, closed cells, and open cells, and these cellular structures influence the final properties of PU foam. <\/span><\/p>\n

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Types of surfactants<\/b><\/p>\n

Thus, two main groups of surfactants can be distinguished, foam stabilizers and cell regulators.<\/span><\/p>\n

Foam stabilizers are surfactants used in critical PU formulations, i.e. formulations that due to the type of chemical nature of the components of polyols and \/ or isocyanates or due to the amounts of catalysts or water, have very little stability. In these cases a surfactant with stabilizing capacity is required, which helps in the foaming process in the expansion of the gases. We find this type of surfactant in formulations where only TDI or TDI \/ MDI mixtures are used, but with a high percentage of TDI.<\/span><\/p>\n

Secondly, there are cell regulators. These surfactants are primarily designed to regulate and unify the size and distribution of cells. These surfactants are aimed at PU formulations that by themselves already have a high stability, able to grow with a solid and consistent structure without collapsing, without the need for the help of a surfactant. We find this type of surfactant in formulations where only MDI or TDI \/ MDI mixtures are used, but with a high percentage of MDI. Cell openers are often requested on the market, which are cell regulatory surfactants that increase the size of the cell to prevent shrinkage problems.<\/span><\/p>\n

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Flexible HR PU foam<\/b><\/p>\n

Concentrol surfactants in the STB PU-12XX range are driven by high resilience PU foam, HR. HR formulations have different needs for cell stabilization and regulatory efficiency, as we find TDI, MDI systems or mixtures of these. Therefore, a wide range of additives must be offered to meet all possible requirements. However, these systems are usually quite stable and a well-balanced foam opening is usually sought.<\/span><\/p>\n

One of the most common requirements is low compressive strength. The optimal level of compression can be achieved with the proper selection of surfactant.<\/span><\/p>\n

At the same time, due to the increasingly stringent legislation requirements of the automotive and mattress industry, the minimum contribution to volatile component emissions is sought.<\/span><\/p>\n

Emissions are classified into VOC (volatile organic compounds) and FOG (fogging organic compounds). VOCs, which include VVOC (very volatile organic compounds) and VOCs, are easily released from PU foam in a closed car in the summer, when internal temperatures between 25 \u00b0C and 90 \u00b0C can be reached. FOGs are the sum of VOCs and SVOCs (semi-volatile organic compounds) that evaporate at temperatures above 90 \u00b0C.<\/span><\/p>\n

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Evolution of Concentrol’s range<\/b><\/p>\n

Given the casuistry of the sector, in Concentrol the lines of surfactants have evolved in the following direction:<\/span><\/p>\n

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