TPE: Thermoplastic Elastomer
TPE has the advantages of both rubber and plastic and has a wide range of applications. It can be used for reinforcement and toughening modification of plastics. It is a kind of energy-saving and environmentally-friendly rubber and plastics with good prospects. Its compression deformation, elastic recovery, and durability are inferior to those of the same rubber, and the price is often higher than that of similar rubbers.
TPE vs TPR
- TPE is generally modified with SEBS as the substrate, and TPR is generally modified with SBS as the substrate. SEBS has a saturated molecular structure, and its aging resistance, yellowing resistance, temperature resistance, and corrosion resistance are better than those of SBS. Therefore, the related properties of the same TPE are better than those of TPR.
- The surface of TPE particles is matte or matte, which has light irradiation astigmatism, while TPR particles are bright and have light reflectivity, especially for transparent materials. TPE feels comfortable and smooth, while TPR is a little sticky, especially when the temperature is above 30-40 ℃.
- In products that need to be glued, such as shoe materials, handicrafts, toy dolls, etc., TPR materials are generally used, because TPR and glue are relatively strong, while TPE materials and glue are almost non-stick. In addition, TPR is suitable for making products with bright colors. , products with bright surfaces.
- Both TPE and TPR have the plasticity of plastic and the elasticity of rubber, while the TPR molecule has an unsaturated molecular structure similar to rubber, so it has the feel and resilience of rubber.
- The difference between TPE and TPR combustion: TPE combustion produces light smoke, while TPR combustion produces darker smoke.
The Manufacture of TPE Extruder
Introduction of TPE production process
Generally, it is an extruder (rubber-plastic blending process) or a reaction kettle (special elastomer) using a chemical synthesis process: reaction kettle + melt pump + underwater pelletizing process.
Materials required for TPE granulation: basic material PP/PS+SEBS+oil+(calcium powder)+stearic acid+antioxidant, etc. (seals, handles, etc.).
Common granulation process:
(1) Twin-screw extruder + underwater pelletizing
(2) Twin-screw extruder + water ring pelletizing
(3) Twin-screw extruder + strand pelletizer (special soft rubber pelletizer can be cut with a Shore hardness above 20 degrees, preferably a Shore hardness above 50 degrees)
The advantages of TPE extruder in TPE extrusion granulation
For TPE as an elastomer, the most difficult process is how to granulate. In the selection of extruder, the extruder model of 52mm-95mm is usually selected, L/D is 48:1, the screw material is W6Mo5Cr4V2, and the barrel is block type, 45# steel + overall sleeve structure.
After TPE is blended and modified by a twin-screw extruder, it is difficult to extrude and form, and the traditional strand pelletizing cannot meet the demand. Cowin’s underwater pelletizing unit can solve the problem for customers! After the blended and modified TPE melt is extruded out of the template, the blade quickly dices the material without sticking or wrapping the knife, and the particles enter the cooling water pipe at the fastest speed. The cutter adopts a new compensation structure, and the blade is welded with cemented carbide, and the service life can reach up to half a year. The adjustment and feed of the cutter are pneumatic and automatic feed. The centrifugal dehydrator preliminarily spins and dehydrates the cut particles, and contains a stainless steel cyclone separator.
Customer Location: Xiamen, China
Machine model: CHT65B Twin Screw Extruder with Underwater Pelletizing Line
Material name: TPE
Time: April 5, 2021