Plasticization

Plasticization (made-up word in the sense of “being softened”) describes the transition of a substance from a solid to a deformable or flowable state, it is then plastically deformable .

The term is specifically used in various fields.

Plasticization in technology

Plasticization is a manufacturing process to facilitate or enable further processing.

Plastic:

• In plastics production , plasticization is the conversion of powdery or granular plastics through temperature and pressure, i.e. a reduction in the viscosity of the material. Here, the plastics are heated above their specific melting temperatures in processing machines (e.g. extruders , calenders or injection molding machines ) so that they form a hot, homogeneous plastic mass. If the plastic is then plasticized, it can in the further process z. B. to tubes, plates, foils or injection molded parts. Coating, also called plasticization , is also possible in this way. The term is used analogously in recycling technology, where it denotes plastic recycling by grinding and remelting collected old plastic mixtures. A minimum of 60% thermoplastics (collective term for plastics that result from the polymerisation of alkenes (ethylene, propene)) polyolefins must be present.
  
• In addition, one describes as plastification , engl. plasticizing , the addition of plasticizers to plastics, i.e. chemical substances that affect the elasticity of the material.

Wood:

• Wood is plasticized by steam treatment so that it can then be bent or pressed. The process is now also known as steam forming , and was developed industrially for bentwood around 1830 by Michael Thonet for seating furniture; it has been known since ancient times and was used, for example, in cooperage .
• The chemical treatment of wood fibers in the production of MDF panels, chipboard or wood-plastic composite products is also known as plasticizing . Such wood-based materials are pressable and also bendable, so they can be extruded or deep-drawn .

Mortar / concrete:

• Additive to reduce the brittleness in the hardened state by additives that allow minimal sliding of the crystals in the material against each other. B. by introducing micropores. Plasticizing cement aggregates reduce the risk of cracking e.g. B. with thermal expansion, but also usually reduce the ultimate strength of the material. In general, plasticizing cement aggregates also improve (reduce) the depth of water penetration and improve frost resistance.

See also: thixotropy , softening of special materials by kneading, shaking and the like.

geology

Two forms are summarized under the term plastic rock :

• Lava that is primarily plasticized by high temperature - lava is a phenomenon of volcanism in the earth's crust
• Magma that is liquefied at extremely high temperatures. One speaks of magma in the interior of the earth.

Individual evidence

1. ↑ Umweltlexikon-online ( Memento of the original from January 4, 2011 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.