Plastic granulate

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Granulate made of PE-LD with carbon black as UV stabilizer
Polyamide granulate, type 4.10

Plastic granulate is the typical delivery form of thermoplastic plastics raw material manufacturers for the plastics processing industry. Because of its pourability, it is a bulk material such as sand or gravel and is therefore just as easy to transport as these. But there are also so-called melt granulates for end users.

Manufacturing

After polymerisation and, if necessary, compounding , the plastic is initially in the form of a melt in the extruder . This is then formed into strands via nozzles and cooled in air or water. Then a rotating knife cuts the strands into sections a few millimeters long, the granulate. This can now be transported in pipelines or packed in sacks or other containers.

use

The plastics processor uses the granulate for injection molding or extrusion . In both cases it is again melted in an extruder by the action of heat and then injected into a special mold with great pressure (injection molding), passed through nozzles (film extrusion) or, as a combination of the two processes, blown into a mold ( blow molding ).

Hollow bodies are produced from granulates with a specified grain size distribution using the rotary melting process / rotary molding.

Rubber granules

Rubber granules are granules made from synthetic rubber , e.g. B. shredded old tires or EPDM with grain sizes between 1 and 3.3 mm the z. B. be used for elasticity purposes in artificial turf or running tracks . Recycled granulate is classified as harmless to health by the European Chemicals Agency (ECHA), although only the local potential effects of (inter alia) PAHs on sports enthusiasts were assessed.

Environmental impact

Plastic granulate in the rinsing hem on Scharhörn

Plastic granulate easily escapes from the production and processing chain into water and represents a large proportion of the microplastic or plastic waste in seas and on coasts. It is therefore often found in the digestive tract of sea birds and marine animals.

Web links

Commons : Plastic Granules  - Collection of Images, Videos and Audio Files
Wiktionary: Plastic granulate  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. ↑ Entry on rubber granulate at baunetzwissen.de .
  2. ↑ ECHA: Report according to Annex XV - An assessment of the possible health risks of recycled rubber granulate used as filling material in artificial turf playing fields , 2017.
  3. ↑ Simon Hann et al .: Investigating options for reducing releases in the aquatic environment of microplastics emitted by (but not intentionally added in) products , 2018.