Thermoplastic

Thermoplastics ( singular: the, from Ancient Greek: thermos = θερμός warm, hot and πλάσσειν plassein = form, shape ), also called Plastomers, are plastics ( thermo- plastic) can deform in a certain temperature range. This process is reversible, i.e. it can be repeated until in the molten state as often by cooling and re-heating, while not using a result of overheating, the so-called thermal decomposition of the material. In it thermoplastics differ from thermosets and elastomers. Another unique feature is the weldability of thermoplastics.

Structure and Classification

Thermoplastics are branched from a little or not, so constructed linear carbon chains, which are connected to each other only by weak physical bonds.

These binding forces are more effective when the chains are aligned in parallel. Such areas are called crystalline as opposed to amorphous ( disordered ) areas, in which there are entangled macromolecules.

If different thermoplastics are mixed together, it is called the product a polyblend.

Thermoplastics can be welded under the action of heat and pressure, this is possible with or without filler material. The materials to be welded are thereby heated above their melting temperature, and is brought into a flowable state. Because this is done for different polymers at different temperatures, in addition to the same species only plastics with similar melt indices may be mutually welded, for example, PMMA with PVC.

Processing

Thermoplastics were originally mainly processed by injection molding, which is why they are also called gunning (unlike thermosets, called molding compounds ). Today, the extrusion is another important processing methods. Other processing options are eg blow molding, film blowing, staking and calendering. In principle, thermoplastics also edit mechanically and thermally. Under mechanical processing to mean, for example, sawing, milling, grinding, turning, planing and joining processes bonding and welding. The thermal processing methods include, for example, the free deformation over a tool and vacuum forming.

Aggregate states

Festival

Before heating, and after cooling, thermoplastics are fixed, which does not mean the same stiff. Many thermoplastics are also flexible in the solid state and some can also be edited in the solid state and changed in shape.

Thermo Elastic

In the area where a thermoplastic resin is heat- elastic, it can be changed in its shape, but retains its original shape and can be returned to it.

Thermoplastic

The material softens and is no longer stable in shape, so it can not possibly be returned to its original shape (for example, pipes ).

Liquid

When the range is exceeded, the thermal plasticity of the material is liquid. Upon further heating the material volatilizes and decomposes into its basic components.

Examples

To the thermoplastics include, for example: acrylonitrile -butadiene-styrene (ABS), polyamides (PA), polylactate (PLA), polymethylmethacrylate (PMMA), polycarbonate (PC ), polyethylene terephthalate (PET), polyethylene (PE ), polypropylene ( PP), polystyrene ( PS), polyetheretherketone (PEEK), and polyvinyl chloride (PVC). The longest known thermoplastic is celluloid. The most widely used thermoplastics are polyolefins such as polyethylene and polypropylene.

Shopping / Commercial thermoplastics

Thermoplastics are traded in Western Europe for the most part directly between producers plastic and plastic processors. For specialties, small quantities, in regionally or nationally designated areas are in part still called distributors switched between.

A comprehensive synopsis of the price development of thermoplastics in Europe offers a commodity index, the so-called Plastixx. Since the beginning of 2004 the raw materials LLD polyethylene and polypropylene are also traded on the London Metal Exchange ( LME) as commodity futures contracts ( futures). Since mid-2007 there is also a different regional pricing ( for Asia, Europe, North America) on this system to reflect the market situation in more detail.

• Thermoplastic