PLEXIGLAS® Terms

The liquid, fully colored monomer is cast between two mirror glass sheets, where it is cured into acrylic glass. The use of textured panes of glass provides acrylic sheet with textured surfaces.

In many plastics applications, the question of resistance when the plastic comes in contact with particular agents or materials is of concern. The simplest method of testing a plastic’s chemical resistance consists of bringing specimens into contact with the agents in question without adding any extra stress. This is accomplished by immersing the plastic into liquids or, in the case of solids, placing the solid on the surface of the plastic. The changes in appearance, weight and strength that may result after storage then serve as evaluation criteria.

In extrusion technology, the term “coextrusion” stands for the bringing together of identical or different plastic melts before extruding them through a single die.
The multilayer composite sheets produced in this way can be classified as follows:

Identical composites: e.g., acrylic glass with acrylic glass
Different composites without adhesion promoters: e.g., ABS / acrylic glass
Different composites with adhesion promoters: e.g., ABS / polymer / acrylic glass

The multilayer composites sold in the sanitary market are different composites. The coextruded different composite sheets primarily consist of a plastic named acrylonitrile butadiene styrene – ABS – (90 to 95%) and have only a thin acrylic coating (only 5 - 10% of the total sheet thickness).

(see Lightfastness / yellowness index)

Adding and mixing colorants into plastics.

Elasticity refers to the ability of a material to regain its shape after the removal of an externally applied mechanical stress (elastic modulus).

The elastic modulus is the constant ratio of stress and deformation within the elastic limits of a material (elasticity).

The elastic modulus of cast and extruded sanitary acrylic equals 3,300 MPa.

PLEXIGLAS^® grades made by Röhm GmbH meet the most stringent environmental requirements.

The PLEXIGLAS^® grades contain no bisphenol A, no harmful heavy metals and no harmful plasticizers.

In extrusion, the pure, fully colored acrylic granules are melted in an extruder and then smoothed on both sides between high-polish, hard-chromium-plated steel rollers and calibrated. Sheets manufactured in this manner feature an outstanding surface quality and thickness tolerance. The use of textured rolls provides sheets with textured surfaces.

Resistance to discoloration and changes in physical properties under the action of light. Light resistance is a general term and refers to changes in properties under the action of light in general.

(Transparency)

Light transmittance is a measure of how well a material transmits light that is perpendicularly incident to the surface. The spectral transmittance of colorless PLEXIGLAS^® grades for perpendicular incidence in the visible range is a constant (92%). The peak value of 92% can be attributed solely to physically-caused reflection losses of 4% each at the light admission and light emission surfaces.

Since PLEXIGLAS^® has no color of its own, it can be colored with extraordinary precision and into nearly any shade.

This refers to the physical state in which the atoms or molecules of a substance (e.g., acrylic glass) are no longer able to move freely in relation to each other because their thermal motion has been frozen. This means that the molecules solidify to form a solid. This applies to all acrylic glasses.