Application of TPU on shoe materials

TPU is a common high-quality and multifunctional material, it has a strong tension and tension, with excellent tenacity and anti-aging characteristics. As a kind of elastomer is a material between rubber and plastic, its biggest characteristic is extremely hardness, and elasticity, this performance is not other rubber and plastic.

What are the characteristics of the TPU?

Wide range of hardness

By changing the proportion of each reaction component of TPU, the products with different hardness can be obtained. With the increase and decrease of hardness, the products still maintain good elasticity and wear resistance. Applied to the sole can be adjusted according to different ground conditions, to provide different hardness and grain design, to meet the needs of different occasions of wearing.

High mechanical strength

TPU tensile strength and tear strength, hardness and elasticity of TPU are very good, so the impact resistance and shock absorption performance of TPU products are excellent.

Excellent temperature resistance

TPU generally has good temperature resistance. The temperature for continuous long-term use is 80~90℃, which can reach about 120℃ in a short time. The low temperature resistance is also good, maintaining good elasticity, flexibility and other physical properties at minus 35 degrees.

Good processing performance

The TPU can be processed by conventional thermoplastic processing methods, such as ejection, extrusion, calendering, blow molding, molding, etc. Meanwhile, the TPU can be processed together with some polymer materials to obtain a polymer alloy with complementary properties.

Application of TPU on shoe materials

TPU (thermoplastic polyurethane elastomer) is widely used, and sports shoes is its downstream application of a big market, is widely used in shoe outsole, shoe sole, air cushion, shoe decoration, upper yarn, waterproof wet film, hot melt film, 3D printing, etc., and the resulting 100% TPU sneakers concept, many companies have launched the corresponding TPU material solutions, has the characteristics of recycling, environmental protection and sustainable.

The following is the application of TPU in sports shoes. In order to understand, we will organize TPU sports shoes according to three main components, namely, vamp, shoe midsole and shoe outsole.

Vamp-TPU yarn and TPU synthetic leather

Breathable woven upper and waterproof leather upper are common sneaker upper. Among them, flying weaving refers to the whole vamp integrated woven forming, can be woven by TPU yarn,  soft texture and very durable, and high wear resistance, easy to hot pressure 3D plastic, solid, etc.

In addition to yarn woven upper, TPU can also be made into synthetic leather for upper, decorative pieces, etc.

The midsole of the shoes: ETPU

Shoe midsole is the most popular and most mature part of TPU sports shoes. The common process is to make TPU into foaming particles through the supercritical kettle foaming process, combined with water vapor or microwave molding to get ETPU shoe midsole. Compared with the traditional EVA midsole, the E-TPU shoe material has excellent resilience, very low compression permanent deformation, and good wearing sense.

In addition, in the TPU insoles, there are also prepared through the foaming process, first foaming into sheets and then cutting, but the current application is still very few.

Sole: wear-resistant, antiskid, TPU

TPU can get the shoe outsole through injection molding, which has the characteristics of wear resistance and high strength. In addition, the anti-slip effect is also one of the important indicators to judge the performance of TPU sole.

In addition to the above introduced vamp, midsole, outsole, TPU in the shoe industry and anti-torsion tablet, heel sheath, Hong Bao (hot melt glue), film and so on, is very widely used.