Indestructible! Thermoplastics—the always reusable plastics

Related Vendor

FAULHABER Drive Systems

Plastics, more scientifically referred to as polymers, are generally classified into three types—thermoplastics, thermosets (formerly known as thermosetting plastics), and elastomers. Here are the basics of thermoplastics.

What characterizes a thermoplastic? The most important feature is that thermoplastics can be reprocessed repeatedly because they, like candle wax, can be remelted over and over. This makes them the most recyclable plastics. Thermoplastics can be processed into components using any common plastic processing method. These mainly include injection molding (complex parts, like housings), extrusion (tubes and profiles), thermoforming (large-area parts, such as bathtubs), and blow molding (films or bottles). For injection molding and extrusion, the plastics are needed as granules, i.e., as free-flowing particles. In thermoforming, sheets or thicker films are processed. Many thermoplastics are also offered with added short glass fibers, which enhance their mechanical properties.

Well-known representatives of thermoplastics in everyday life

The thermoplastics we encounter daily mostly belong to the category of polyolefins. We carry our groceries home in polyethylene bags (LD-PE = Low Density Polyethylene) and pack fruits or vegetables in a crinkling variant, HD-PE (High Density Polyethylene). Bottles and canisters are also made from it. More mechanically robust is the polyolefin polypropylene (PP), known from margarine tubs. All polyolefins are chemically very resistant, relatively tough, and can be defined as a kind of harder candle wax. However, they withstand only up to about 140 °C (284°F, only applicable to PP).

We also very often encounter polyethylene terephthalate, or PET, in the form of beverage bottles manufactured through the blow molding process. However, it no longer belongs to the polyolefins! And certainly, everyone is familiar with thermoplastic polystyrene (PS), which in its foamed variant has long been used in everyday life and packaging technology as Styrofoam (but PP and PE can also be foamed this way). In compact form, PS is known, for example, as a CD case.

Polyvinyl chloride (PVC) also frequently encounters us. It was the preferred everyday plastic after World War II in the 1950s and 1960s. It is processed into floor coverings, films, and hoses and is chemically very resistant. It is available in both soft and hard versions.

And in the bathroom and shower, another thermoplastic is often found, known as Plexiglas or acrylic glass! Technically, it is referred to as PMMA (polymethyl methacrylate). It is used to make bathtubs and shower trays (thermoforming), as well as optical components.