ETPU materials are superior to EV materials.

EVA is a random copolymer composed of ethylene and vinyl acetate, wherein vinyl acetate as a flexible chain segment of EVA molecular chain, ethylene as a crystalline chain segment, the whole shows a certain softness and high elasticity.

In terms of technology, EVA is generally foamed in chemical mold in the shoe industry. EVA granulation material is put into the foamed mold and then foamed at high temperature and high pressure. The foam EVA can make the sole lighter, and the EVA resin with a certain elasticity makes the sole have appropriate cushioning function, so that EVA foam shoe material to meet the needs of most casual shoes and jogging shoes. After foaming, EVA resilience can be improved to 50-55% or even higher.

EVA blend foaming products are widely used in middle and high grade travel shoes, hiking shoes, slippers, sandals soles and interior materials. In addition, due to the price advantage of EVA foam material, it will still be the most important material choice for public sports shoes in the future for a long time.

TPU is a thermoplastic polyurethane elastomer, which is a block copolymer composed of diisocyanate, chain extender and polyol. Among them, the soft segment composed of polyols shows flexibility and toughness, while the diisocyanate as the hard segment gives the material hardness and rigidity, and the hard segment acts as the physical crosslinking point after crystallization, making the TPU show high elasticity. Therefore, TPU has the advantages of high tensile strength, large elongation and low permanent deformation rate under long-term compression.

In terms of technology, the ETPU center sole adopts physical foaming, which has no taste compared with the chemical foaming of EVA, and is environmentally friendly and recyclable. After forming, it takes on the shape of popcorn, with excellent resilience and deformation recovery, and the wear resistance and skid resistance are far superior to traditional EVA material. After foaming, the rebound value of foam falling ball can reach 60%, which is significantly higher than that of EVA. When shoes bounce back from the ground, the sole hits the ground with higher strength, effectively reducing muscle fatigue and muscle shaking, so that you can run further with full motivation.
However, the price of ETPU is higher than that of EVA, which makes some manufacturers shy away, and there is a certain difficulty in process innovation. However, these are temporary. There have been many manufacturers trying to bring ETPU material to a wider range of downstream applications. For example, ETPU plastic racetrack was successfully commercialized, and in recent years, more commercial applications appear in our vision. Examples include ETPU bike seat pads, sports protection pads, ETPU children's crawling pads, bicycle helmet fillers, car seat fillers, etc.

Generally speaking, the price of ETPU is higher than that of EVA, but ETPU is much better than EVA in terms of resilience, deformation recovery, wear resistance and skid resistance. And most importantly, ETPU is in line with the general trend of green environmental protection.