Plastic gear material shows no water absorption after 700 hrs submerged in water

Ordinary plastic gears expand when they absorb moisture, internal stresses are relaxed, and the tensile strength drops by 50% or more when fully saturated. Changes in internal stress can alsocause plastic gears to lose their shape. When that happens the weakened gears don't mesh smoothly, and teeth wear out prematurely, chip, or break.

The plastic composite outer layer of the Power-Core gear does not absorb moisture. It loses less than 10 % of its tensile strength - and grows less than 2% (a negligible amount in gear design) - even when immersed in fluids.

Below is a graph that shows how even after 700 hours submerged in water, the Intech Power-Core material still shows no evidence of water absorption.