When a vulcanized rubber with the ability to swell is submerged in a solvent it will slowly start to swell.

This is possible because the osmotic pressure is larger than the force holding the molecules of the polymer together. During this period of time the solvent will enter the rubber. Depending on the size of swelling this could lead to a decrease of properties. However, this phenomenon can also be used for special applications were swelling is desirable like the waterproofing of structures and tunnels.

QEW Engineered Rubber has Swellable Waterproofing Compound (SWC) available for waterproofing solutions in structures and tunnels. This rubber will swell significantly in water. So far a rubber has been developed with the ability to swell over 5-7 times his original size in one week.

Very soon we will have a full range of compounds with different swelling behavior. For example one compound should only swell up to twice its original size while other should swell three, four or more times.

Available in compound, vulcanized extruded cord or strip and sheets. Like all QEW rubber compounds it has the highest quality and is always “ready to use”.