A few decades ago, the footwear industry was searching for an alternative to the conventional sole materials to create a more robust, stylish and sustainable sole. The quest saw a new hope when the sole manufacturers had caused a disruption with an intriguing and innovative material - Polyurethane (PU).
The PU sole manufacturers have been endorsing and providing this splendid sole material for several years to create a plethora of footwear. The primary reason for its popularity is that the PU sole advantages the footwear manufacturers as well as the end users to a great extent with its amazing properties.
The polyurethane has been extensively utilized as a shoe sole material to develop robust and sustainable high-quality shoes for the applications requiring rough use such as trekking, sports, labour-intensive industries, etc. However, the PU sole manufacturers have made it possible now for them to be used as a sole material for causal and office footwear like formal shoes, sport shoes, safety shoes, sandals, sneakers, chappals etc. Moreover, the constant endeavours of the PU sole manufacturers and the continual demand for this material by the footwear industry, have now made the polyurethane quite affordable. The reasonable cost of the PU sole makes it suitable to be used in more types of footwear than its conventional counterparts.
The polyurethane is produced by reacting an isocyanate prepolymer, such as methylene diphenyl isocyanate, and a polyol component in the presence of heat and an organometallic catalyst.
The liquid Polyurethane produced from the reaction can then be shaped into the required sole designs using injection moulding or pouring method. As the former has more merits, it is usually the most favourable method for the production of PU sole. By varying the diverse factors such as the types of the key or additive components and their contents, the density and hardness of polyurethane can be altered to produce the material with diverse characteristics.
To ensure that the PU sole advantages the footwear manufacturers with its use in a broad range of footwear, the PU sole manufacturers have developed mainly two versions of the polyurethane.
The highly competent characteristics of PU sole advantage the footwear manufacturers and consumers alike and this has rightfully made it the soul of the footwear industry. Here are some of these advantages: