- What's the Difference?
In order to understand the advantages of the ImmerSeal® system over wet applied sealants we should explore how the two systems perform.
ImmerSeal® is an ultra low modulus silicone extrusion designed for extremely high extension and compression capabilities while exerting very low tensile or compressive forces. Unlike other elastomers which function generally as compression seals, ImmerSeal® is bonded to the substrate using an adhesive sealant. Due to the unique physical properties and relatively thin cross-section (~ 2 mm) of ImmerSeal®, only minimal bond-forces are generated during compression and extension movement of the substrates. This crucial feature is new to the sealing industry and provides consultants, engineers and designers with new ways to create high performance seals, expansion joints and waterproofing systems.
It is critical not to confuse ImmerSeal® extruded silicone profiles with compression seals. It can be described as a passive seal, a seal that is being moved instead of withstanding movement. Furthermore, since ImmerSeal® is manufactured using 100% Silicone, a long service life is certain. Similar products made of organic materials can not be manufactured at such a small thickness while achieving such exceptional aging characteristics.
- Joint Movement Performance Comparison
Preformed Silicone Joint Sealants
ImmerSeal® deforms during joint movement, but the deformation during compression is in the form of a bend, which generates very little stress within the material and on the substrates.
Wet Applied Sealants
The volume of a wet applied sealant does not change during movement of a joint, but the sealant cross-sectional shape is deformed during extension or compression. During this deformation, stress and or high pressure related forces strain the bond area.
These photos show the high movement capability of ImmerSeal® as viewed during an adhesion test.
- Performance Analysis
Unlike Preformed Silicone Joint Sealants, wet applied sealants experience much higher compressive forces than tensile forces at the same amount of movement. High compressive forces can be detrimental to the sealant adhesion and may damage fragile or sensitive substrates. Lab results have shown that sealants fail during elongation after compression cycles.
When comparing the forces generated by preformed silicone joint seals to wet applied sealants experiencing equal movement, the results might be surprising. Compressive and tensile forces generated during movement are much lower for Preformed Silicone Joint Seals than those generated when using conventional wet applied sealants. Since the forces on the adhesive bonds of preformed joint seals are so low, the adhesion should last a long time, even on difficult to adhere to surfaces. Therefore, ImmerSeal® systems are the best choice to use on sensitive substrates such as EIFS, sandstone or grout, where most normal wet applied sealant systems will pull the substrate apart at the surface.
Technical data obtained from ASTM "Science and Technology of Building Seals, Sealants, Glazing, and Waterproofing" vol. 7, Jerome Klosowski, Editor. Authors: Peter R. Hagen, Gregory E. Mayville and Jerome M. Klosowski. Reprinted with permission, from STP 1334-Science and Technology of Building Seals, Sealants, Glazing, and Waterproofing: Seventh Volume, copyright American Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428