Construction Sealants are normally Shore A 25 to 35 compositions used to fill joints in concrete and brick facades exposed to weather and sunlight. It is important the polymer is flexible, with good recovery from joint expansion and good UV resistance. The best Polymers for this application are the long chains of PPG terminated with trimethoxy silanes, where the composition uses a isocyanato propyl trimethoxy silane, with some addition of plasticizers, precipitated calcium carbonate reinforcing filler and low levels of catalyst. We have low viscosity STP polymers that are Patented by us.
We are manufacturing our TMS 30000 Polymer now in Australia , and sealants using this Polymer meet the new low tin catalyst requirements introduced by REACH in Europe. Sealants using this Polymer are Paintable.