Lightweight, Comfortable Sport Soles Now Made with Polyurethane

Lightweight and Comfortable Sports Insoles Meet Polyurethane In an increasingly active sports world, athletic shoes are an essential part of our lives, whether we wear them for professional activities or casual short walks. The insole is the most critical component in sports shoes, where comfort and lightweight properties are most expected to be felt. The qualities users seek in a good insole are its ability to withstand the force applied at each step throughout its service life while providing nothing but comfort. Sports insoles are typically manufactured at densities of 400 kg/m³ and higher in the sector. Due to rising costs and the lighter weight of insoles produced with EVA (ethylene vinyl acetate), polyurethane's competitor, demand in the sector has increased for low-density products. Flokser Kimya develops polyurethane systems meeting this market need in response to customer demands. Our company's Creacat H-460 product, introduced in previous years to meet customer requirements, operates at mold densities of 380-420 kg/m³ and hardness of 44-50 ShA. This product has gained acceptance in the sector and is actively used in the production of sports insoles that stand out for their lightweight properties in the market.   To capture EVA's lightweight advantage while providing additional weight savings and comfort, Flokser Kimya has again set market direction by developing an ultra-lightweight new sports insole system. The Creacat H-466 system, which operates at mold densities of 320-400 kg/m³ and has hardness similar to standard polyurethane sports formulations, has been introduced to the market for this purpose. This system brings EVA's lightweight advantage into the polyurethane world, while simultaneously providing approximately 25% weight savings compared to standard polyurethane sports insole systems used in this market. [caption id="attachment_141370" align="aligncenter"] Figure 1. Ultra-lightweight polyurethane (PU) sports insole providing approximately 25% weight savings[/caption]   The comparative product properties of our Creacat H-460 and newly developed ultra-lightweight Creacat H-466 sports insole systems are presented in Table 1. This product launched to the market demonstrates mechanical properties close to the H-460 product in tensile strength, tear strength, and flex testing. Despite H-466's low density, its mechanical properties comparable to other products actively used in the market will enable our customers to work with the product confidently. [caption id="attachment_141371" align="aligncenter"] Table 1. Comparative table of our Creacat H-466 and H-460 systems[/caption] *Reaction and working conditions were obtained from measurements using a low-pressure molding machine operating at 6000 rpm. ** Test results are provided following conditioning in accordance with TS EN 12222 standard for 24 hours at 23±2°C and 50% relative humidity. The greatest disadvantage of EVA systems, known for their low-density operation, is their poor wear resistance. In the insole sector, our PU sports insole systems (H-460 and H-466), which provide superior wear resistance performance compared to EVA, are shown comparatively in terms of relative volume loss in Figure 2. In testing conducted according to TS EN 12770 standard, both our sports insole systems show similar wear resistance values. Based on the results obtained, our H-466 product, while operating at densities similar to EVA insoles, exhibits 70% less wear compared to EVA. [caption id="attachment_141373" align="aligncenter"] Figure 2. Relative volume loss graph of EVA, H-460 and H-466 insole systems[/caption] Our low-density sports insole journey beginning with H-460 has taken a new direction with the ultra-lightweight H-466 sports insole system, developed with inspiration from EVA, capable of operating at even lower densities and demonstrating higher performance than EVA in terms of mechanical properties.   Into the future with Flokser Kimya's new systems, developed beyond expectations!     Tibet Hüten Product Development Researcher Flokser Kimya   Kerim Can Ünlü Product Development Manager Flokser Kimya   Kübra Sarper Product Development Specialist Flokser Kimya   Dr. Serpil Yılmaztürk Güney Product Development Director Flokser Kimya