Thermoplastic Polyurethane Imparted with Crosslinking Sites and Method for Producing Crosslinked Foam Using the Same

Abstract

The present invention relates to a thermoplastic polyurethane composition imparted with crosslinking sites, which comprise a thermoplastic polyurethane containing crosslinking sites incorporated into the molecule of a polyol and/or a chain extender. The thermoplastic polyurethane composition has an easy-to-process viscosity at a processing temperature of about 130° C. or below in a low-temperature foaming process that is performed using an existing EVA crosslinking/foaming system. Thus, the thermoplastic polyurethane composition may be easily mixed with a crosslinking agent, a foaming agent and various additives, and when it is press-molded or injection-molded to provide a crosslinked foam, foam cells are easily formed by the crosslinking sites incorporated into the molecule of the polyol and/or the chain extender. In addition, a foam produced using the thermoplastic polyurethane composition has excellent mechanical properties and also has varying specific gravities depending on the amount of the foaming agent used.

Dependencies are inferred from the claim text.