Typical practitioners choose from among only two to three products when selecting liners for their patients. A lack of comparable objective information about similarities and differences among elastomeric liner products may be part of the reason.
Commonly used, commercially available polyurethane, silicone, and thermoplastic elastomer (TPE) liners were tested for their compressive, shear, tensile, and volumetric elasticities as well as their coefficients of friction (CoFs) and thermal conductivities.
Polyurethane and silicone liners tended to be stiffer in compression and shear than TPE liners. Fabric backings contributed primarily to increased tensile elasticity (and thus reduced pistoning). Polyurethane liners demonstrated relatively low CoFs, whereas silicone and TPE liners had higher CoFs and wider ranges. All materials tested were essentially incompressible. Thermal conductivities of all materials were comparable and similar to that of leather.
Polyurethane liners are softer and less sticky than 16 years ago, and TPE liners have higher tensile stiffness than previously. A stiff fabric backing can increase tensile stiffness by more than 200%. Compressive stiffness may be used to characterize a liner’s ability to flow. Elastomeric liners move heat almost exclusively via conduction.
JOHN C. CAGLE, PhD; NICHOLAS TAFLIN, BS and JOAN E. SANDERS, PhD, are affiliated with the Department of Bioengineering, University of Washington, Seattle, Washington.
BRIAN J. HAFNER, PhD, is affiliated with the Department of Rehabilitation Medicine, University of Washington, Seattle, Washington.
Funding disclosure: This research was based on work supported by the Institute of Child Health and Human Development of the National Institutes of Health under award number R01HD065766.
Disclosure: The authors declare no conflict of interest.
This research was based on work supported by the Institute of Child Health and Human Development of the National Institutes of Health under award number R01HD065766. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Correspondence to: Joan E. Sanders, PhD, Department of Bioengineering, 355061 3720 15th Ave NE, University of Washington, Seattle, WA 98105-5061; email: firstname.lastname@example.org