Method and Flexible Lattice Foams

A method of making a foamed footwear component, comprising

• a) forming a structure of interconnected, unfoamed, thermoplastic polymeric members spaced to define openings therebetween, the thermoplastic polymeric members comprising a thermoplastic polymeric composition, wherein the structure has a first major face and an opposite second major face separated from the first major face by a thickness of the structure, further wherein the structure has openings in and extending at least substantially perpendicular to the first major face;
• b) heating the thermoplastic polymeric members to a first temperature below a temperature at which the structure collapses to produce softened thermoplastic polymeric members, and infusing the softened thermoplastic polymeric members with at least one inert gas at a first pressure that is sufficient to cause the at least one inert gas to permeate into the softened thermoplastic polymeric members and produce infused thermoplastic polymeric members;
• and
• c) reducing pressure from the first pressure to a second pressure below the first pressure while the infused thermoplastic polymeric members are softened to foam the infused thermoplastic polymeric members, wherein at least a portion of the second major face abuts a solid surface that prevents or slows expansion or further expansion of the structure in a direction toward the solid surface.