Silent Feet uses an advanced polymer technology to
absorb vibrations caused by appliances such as refrigerators and washing
machines. The material, called Sorbothane, is said to have achieved shock
absorption levels of up to 94.7 percent.
Sorobothane is a thermoset,
polyether-based polyurethane that has a high damping coefficient and maintains
its property over a wide temperature range. Its unique effectiveness derives
from the fact that it's a solid that flows like a liquid under load and retains
excellent memory. Other polyurethanes and rubber are one-dimensional under
load. Sorbothane's visco-elastic properties mimic human flesh. The elastic
properties of rubber return energy to the system. The material is custom molded
using the resin transfer molding process at Sorbothane's manufacturing location
in Kent, Ohio.
Another interesting aspect of the process is its use as a middle, or
"constrained" layer, between two structural layers, or as an "extensional"
layer on top of a structural layer. It's produced in a durometer range from 25
to 85 Shore "00" Scale.
Sorbothane, first developed in
1982, has been widely used as a shoe insole, as well as for a variety of
engineering applications. Silent Feet are newly engineered pads that feature
two "easy-slide" rear feet and two "super-sticky" front feet.