Molded polymer articles for use in low temperatures having a low rigidity factor

摘要

Ski boots and other cold weather articles are described made from polymer compositions that are exceptionally stable at low temperatures. The polymer composition, for instance, may contain a thermoplastic polymer, a thermoplastic elastomer, and an impact modifier. In one embodiment, each of the individual components are selected such that they do not undergo a second order transition within a temperature range of from about 50° C. to about −40° C., and particularly from about 23° C. to about −40° C. In one embodiment, the polymer compositions are used to mold the outer shell of a snow ski boot.

主权项

1. A boot comprising:
a rigid outer shell having an exterior surface and an interior surface; a lining adjacent to the interior surface of the outer shell, the outer shell and lining defining an opening for receiving a foot of a wearer; and wherein the rigid outer shell is formed from a molded polymer composition, the polymer composition comprising a thermoplastic polymer, a thermoplastic elastomer, and an impact modifier, the polymer composition having a rigidity factor of about 2 or less, wherein the thermoplastic polymer comprises a first non-elastomeric polyester polymer and, wherein the polyester polymer is contained in the polymer composition in an amount from about 15% to about 50% by weight, the impact modifier being present in the polymer composition in an amount from about 15% to about 40% by weight, and the thermoplastic elastomer being present in the polymer composition in an amount from about 20% to about 40% by weight, and wherein the polymer composition further comprises a polycarbonate polymer, a non-elastic copolyester, or a second non-elastomeric polyester polymer and is present in the polymer composition in an amount from about 5% to about 15% by weight, the second non-elastomeric polyester polymer comprising a polybutylene terephthalate.