Plastic Substrates

2023 Author: Hannah Pearcy | [email protected]. Last modified: 2023-11-26 11:39

The correct coating is essential when using plastic components.

Plastic components are being used more and more indoors and outdoors. If such areas are to be coated by the painter - regardless of whether it is cladding, windows, doors, pipes, gutters or plastic-coated surfaces - the first question to be answered is: what plastic is it actually?

According to their physical properties, plastics can be divided into three main groups:

1. Plastomers (thermoplastics): These melt when heated, are swellable and soluble through appropriate solvents.
2. Thermosets (thermosets): These are hard, not meltable, not soluble and difficult to swell.
3. Elastomers: These have a high elasticity at normal temperature, are not meltable, cannot be removed, but can be swelled with the appropriate solvents.

The determination is only possible without problems using an existing label. If this marking is missing, it is not possible to determine with certain standard construction site means what kind of plastic it is. In this case, the component manufacturer, the assembly company or the client must be asked; if necessary, the coating manufacturer may also be able to determine the type of plastic by means of laboratory tests and thus suggest the appropriate coating system. The choice of coating materials or systems then depends on the type of plastic and the expected stress.

White, especially dimensionally stable plastic components such. B. Windows and exterior doors must not be coated dark, as deformations can occur due to the heating effect when exposed to sunlight. Dark-colored coatings should only be applied to windows and exterior doors if the window manufacturer describes them as suitable for dark coatings. In very few cases, white plastic windows are suitable for dark coatings!

With some plastics, necessary substrate pre-treatments cannot be carried out when installed, such as chemical etching or flame treatment of the surface. If in doubt, concerns should be reported in writing. The processor can only assume a guarantee if the manufacturer designates the coating material or the coating system as suitable for this purpose.

Note: The BFS leaflet no. 22 lists the abbreviations and their meaning, as well as which type of plastic is unsuitable or suitable for which coatings.

Source: Malerblatt 02/2014