Commercialization of Rate Sensitive Low Density Polyurea-Based Viscoelastic Foams For Head Health Applications
Abstract
This proposal seeks commercialization of a new class of polyurea-based viscoelastic foams with a novel microstructure for Head Health applications that outperform the state of the art polyurethane foams and their currently marketed protective headgear products by a significant margin when tested in various industry and government standard helmet tests. The transmitted gÕs through the same foam thickness (0.5Ó-1Ó) in ACH and Riddell football helmets are reduced by an additional 18% to 320%, depending upon the magnitude of the impact force and test temperature. The superior properties of the UCLA foams are due to their unique microstructure that comprises of large polyhedral cells (300Àm -500Àm) covered with perforated membranes with small apertures (20Àm-70Àm). This makes them strain rate sensitive as the rate at which the air escapes the cells depends upon the loading rate. Thus, even with their uniform microstructure, they behave as an elastically modulated layered composite because the cells stiffen or soften in response to the changing loading rate within the same impact event. Remarkably these multiple-hit viscoelastic foams absorb more energy compared to single-hit Expanded Polystyrene (EPS) material under very high strain rates (1000s-1-5000s-1). These foams are therefore ideal for military helmets which unlike sports and consumer helmets are subjected to blast waves that cause TBI to our warfighters. UCLA foams also derive their impact resistant property from the novel polymer that forms its skeleton. It has a Tg of -50¡C and has a polyurea backbone structure whose soft and hard domains not only remain stable up to 50¡C but undergo relative sliding at very low shear stress. These molecular relaxation processes attain maximum efficiency when the foamÕs cellular structure buckle, bend, and twist to generate very large local shear strains during foam compression. These dissipative processes operate at both very low (-15¡C) and high temperature (50¡C) conditions where their polyurethane counterparts either become glassy or their structure deteriorate to result in total loss of their impact properties. Through coordinated efforts with several industry partners (Riddell, Full90, OÕNeal Helmets, Skechers, STX, Under Armour), optimized foam chemistries and associated lab manufacturing processing steps for several applications have been created. I Corps grant money will be used for commercialization of two lab scale processes and foam recipes that have been developed for Head Health applications as they represent current business opportunities with our industry partners. Foam A with a density of 95kg/m3 is designed to work with a helmet shell, whereas Foam B with a density of 170 kg/m3is designed to withstand impact forces without any shell for soft helmet, soccer headbands, and skull cap markets. There is tremendous potential for use in the military and bicycle helmet markets where the standards require rigorous low and high temperature testing. OÕNeal has the capability and manufacturing capacity to make military helmets for purchase by DoD using the UCLA foams after successful conclusion of the I Corps program. The UCLA I-Corps Teamª consists of Vijay Gupta, who will serve as the PI, Brian Ramirez, a Ph.D. student, will act as the Entrepreneurial Lead, and Eric Schiffer, an active angel investor and former CEO of 99¢ Only Stores with over $1.7 billion of sales and 330 stores, will act as the Mentor. At the conclusion of the I Corps program, G-Foam Technologies (GFT), a UCLA Startup, will be launched. It will actively pursue licensing deals with our industry partners. GFT will license all of Gupta patents from UCLA-OIP. Through the mentorship of Eric Schiffer and training under the I Corps program, both PI Gupta and EL Ramirez would be entrepreneurially competitive. GFT will explore the business opportunities related to military helmets and energy efficient warfighter shoes.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 27, 2017
- Source ID
- W911NF1710054
Entities
People
- Vijay Gupta
Organizations
- Army Contracting Command
- Office of the Secretary of Defense
- University of California, Los Angeles