Several manufacturers of high-performance coatings for application to concrete and metal substrates.
In common with all 2K PU coatings, the presence of moisture affects the reactivity and application properties of the coating. Polyaspartic coatings are no exception, and the flow and levelling properties of the coating can be adversely affected. The reason this occurs is because moisture/water reacts with the isocyanate component accelerating the cure rate and ultimately leading to poor visual properties of the coating.
To standardise the cure rate, an appropriate amount of oxazolidine can be added in order to control the level of moisture that affects the coating. This is particularly important when coatings are applied during conditions of elevated humidity.
In view of the variable humidity conditions that the coatings companies operate in, they needed to develop a product that would perform equally well in all types of weather conditions.
Incozol 2 and Incozol LV were both evaluated for this application. By incorporating between 2-5% of the Incozol products into the polyaspartic ester portion of the formulation, the flow and levelling properties were improved and the working time was extended when the coatings were subjected to conditions of elevated humidity.
Most of the manufacturers opted to use Incozol 2 in their formulations, while the remainder preferred Incozol LV. In this scenario the best solution is somewhat system dependant.
Incozol 2 generally acts as an effective moisture scavenger in polyurethane coating systems. It is used to eliminate moisture from solvents, polyols and prepolymers and from plasticisers and pigments. It removes residual moisture from the formulation and prevents bubbling and down-glossing caused by high moisture levels either on the substrate or from the atmosphere.
Incozol LV is a reactive diluent designed to help producers of polyurethane coatings and sealants attain low VOC systems. It is used in the formulation of two component coatings where it replaces a portion of the polyol component.
In the evaluations, both Incozol products proved effective at removing moisture from the raw materials and the atmosphere. The benefits to the paint manufacturers are:
- Consistent flow and levelling properties for spray applied coatings in all types of atmospheric conditions
- Longer working times for roller applied coatings, thus eliminating roller marks from back rolling
- A standardised paint formulation that can be applied during all types of atmospheric conditions
- Fewer complaints from contractors during application
- Increased customer satisfaction