最重要的事實簡述
- TPEs are ideal for processing using extrusion.
- TPE are usually processed in standard extruders.
- The wide range of compounds enables a multitude of possible combinations.
How are TPEs extruded?
During extrusion, the source material is filled as granules into the screws. The high temperatures within the heated cylinder make the material melt. The nozzle brings the molten material into the desired profile shape. After cooling and solidifying, it can be cut to the desired lengths.
Advantage of TPS: In contrast to other plastics, the shear rates enable additional heat to be applied here. This improves the flow characteristics and reduces energy costs, due to the lower cylinder temperatures possible as a result.
Does the machinery have to be modified or expanded when using TPEs?
Generally no. Extruders designed to produce thermoplastic materials are usually also suitable for processing KRAIBURG TPE materials. It is recommended to use standard three-zone screws with a minimum length of 25 D and a compression ratio of 3.5 to 1 and higher. A barrier screw is advantageous for shearing the material. We also recommend using perforated discs or screens.
What temperatures are recommended when processing TPEs using extruders?
Please always refer to the information provided in the respective data sheets when processing TPEs!
Overall, a temperature of 250 °C should be kept as the upper limit during processing. If the temperatures are higher than those specified in the respective data sheets and the residence times are too long, the material may be damaged.
Find the right TPE solution for your application
Making sure you get the best results: the right materials solutions have been developed for each of your specific applications.
Do machines have to be newly calibrated when using TPEs?
Calibration is generally not necessary. However, harder compounds may require additional devices for support.
Which extrusion tools are used in TPE processing?
For processing TPEs, simple die tools are usually sufficient. However, the die land should be kept as small as possible. Multi-plate tools that are equipped with corresponding flow corrections may be beneficial due to lower longitudinal shrinkage and less warpage of the profiles. This also enables higher production speeds. Important: Sharp tool edges should be avoided, especially when the material escapes.
Frequently Asked Questions (FAQ)
-
Can TPEs that have been processed using extrusion be recycled?
1Some of the thermoplastic elastomers produced by KRAIBURG TPE are part of a closed recycling cycle and can be recycled after the product life has ended.
-
Can TPE profiles be returned to in-process recycling?
1In many cases, it is possible to recycle scrap or edge trims within the production process. They are made suitable for dosing in slow-running shredders and added to the original process in proportions of 2 to 15 percent. Users are thus able to reduce costs and make a major contribution to sustainability through in-process recycling!