Urethane Rubbers AU

The urethane linkages in the hard blocks are capable of a high degree of inter- and intramolecular hydrogen bonding. Such bonding increases the 

As with other block copolymers, the nature of the soft segments determines the elastic behavior and low-temperature performance. TPUs based on polyester soft blocks have excellent resistance to nonpolar fluids and high tear strength and abrasion resistance. Those based on polyether soft blocks have excellent resistance (low heat buildup, or hysteresis), thermal stability, and hydrolytic stability. 

TPUs are noted for their outstanding abrasion resistance and low coefficient of friction on other surfaces. They have specific gravities comparable to that of carbon black-filled rubber, and they do not enjoy the density advantage over thermoset rubber compounds. 

There are other factors that can have an adverse effect on aging. Such factors as elevated temperature, dynamic forces, contact with chemical agents, or any combination of these factors will lead to a loss in physical and mechanical properties. 

Urethane rubbers exhibit excellent recovery from deformation. Parts made of urethane rubbers may build up heat when subjected to high-frequency deformation, but their high strength and load-bearing capacity may permit the use of sections thin enough to dissipate the heat as fast as it is generated. 

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