Lightweight thermally switchable polymer foam for athletic footwear cooling and impact protection

Overview

This solution offers a thermally switchable polymer metamaterial designed for athletic footwear that targets an unprecedented combination of lightweight mechanical robustness and sweat-activated thermal conductivity. The technology is intended to protect athletes from impact while actively managing heat and moisture during activity. By integrating a modified closed-cell octet foam architecture with a biologically inspired protein coating, the material is engineered to remain mechanically strong under dynamic loading while responding to sweat to enhance cooling on demand.

Technical specifications

• Core architecture: Modified closed-cell octet lattice foam, fabricated from tough polymers such as Pebax, designed using additive manufacturing methods
• Coating: Squid ring teeth proteins applied to the lattice structure, providing high thermal conductivity when wetted by sweat or moisture
• Mechanical performance: Demonstrated ability to withstand dynamic, high strain-rate loads at approximately half the weight of state-of-the-art open-cell lattice structures used in current athletic footwear
• Ventilation integration: Cooling channels or vent holes can be incorporated with less than 5% reduction in mechanical properties, enabling airflow without compromising structural integrity
• Tunability: Both the core lattice topology and the squid ring teeth protein coating offer adjustable mechanical and thermal properties to meet specific application requirements
• Validation methods: Dynamic impact testing, helmet insert trials, finite element modeling, and thermal conductivity characterization across temperatures from 20°F to 110°F with variable airflow velocities

Technology readiness level

The technology has progressed through foundational validation funded by the NFL Headhealth Tech Challenge, including high strain-rate dynamic testing and football-specific impact testing at an independent facility. Finite element modeling has confirmed the structural advantages of the modified closed-cell octet design over existing open-cell lattice alternatives. The thermal switching behavior of the squid ring teeth protein coating has been characterized by collaborators at the University of Virginia. Future validation will focus on iterative design refinement with footwear manufacturers, followed by experimental impact testing and full thermal conductivity characterization of the coated system. The technology is currently at a stage suitable for collaborative development with footwear manufacturers.