Shear Thickening Fluid (STF)-Fabric Composites for Ballistic
and Impact Protection
The University of Delaware seeks to commercialize through patent licensing and associated
collaborative R&D unique composites of fabric impregnated with shear thickening fluid (STF)
particulate suspensions.
Technology Description
An impact–resistant composite material has been developed based upon the impregnation of fabric
with compositions of STF. The resulting STF-fabric functions as a ballistic material offering
protection against bullet, knife, and ice pick penetration, as well as blunt force injury with significant
advantages in its flexibility and light weight as compared to existing ballistic materials.
Concentrated colloidal suspensions of very small oxide particles demonstrate a stress-induced
transition to a highly viscous structured material. This shear thickening property has been shown to
convey great utility in the fabrication of energy dissipative devices, such as shock absorbers and more
recently in the fabrication of ballistic fabric composites. Ballistic impact testing of Kevlar® fabrics
impregnated with shear thickening dispersions have demonstrated marked improvement over the
performance of neat Kevlar® fabrics. The exploitation of the energy dissipative benefits of STFs in
solid and foamed composites will provide a range of energy absorptive responses for a flexible
material format.
Benefits
 STF-Kevlar® body armor including vest, helmet, glove, and extremity articles offer enhanced
protection from bullet and fragmentation injury using fewer layers of fabric to reduce weight and
increase flexibility.
 STF-fabrics can utilize nylon and polyester to expand the range and variety of applications
including blast containment/mitigation materials, tires, medical devices, sports apparel, wire/cable
insulation, and emergency protective clothing.
 Its light weight, flexibility, puncture resistance (knife, ice pick, etc.) make STF-fabrics useful for
military and civilian correctional vests.
Patent Reference
UD 05-21
Contact Information
Denise M. Bierlein
University of Delaware
Office of Economic Innovation and Partnerships
IP Coordinator
Telephone: 302-831-4005
Email: deniseb@udel.edu
Kevlar® is a registered trademark of E.I. duPont de Nemours and Company