What is a Thermoplastic Elastomer (TPE)?
TPE’s are low modulus, flexible materials that can repeatedly be stretched at room temperature and return to their approximate original size when stress is released. TPE’s are quite versatile and are used in most market segments, including automotive/truck, agriculture, consumer goods, electrical/telecommunications, firearms, medical/pharmaceutical, sports/leisure, and wire/cable. TPE’s are processed using conventional thermoplastic equipment for extrusion, injection molding, blow molding, blown film, and calendaring. All TPE’s are colorable.
What are the different types of TPE
There are various types of TPE’s, each offering a unique combination of characteristics and properties. The more common TPE’s and their primary attributes are listed below:
SEBS – Styrene-Ethylene/Butylene-Styrene
• Polypropylene Compounded with SEBS Synthetic Rubber
• Lowest Cost, Lowest Performance
• General Purpose, Unfilled, and Filled Grades
• Glossy, Tacky, Clear, Translucent, Opaque
• Soft Tactile Feel
• Low Heat Resistance
• Chemical Resistance (Acids and Bases)
• Hydrolytic Stability
• UV Stability
• Food Contact and Biocompatible Grades
TPV – Thermoplastic Vulcanizate
• Polypropylene Compounded with EPDM Rubber
• Moderate Cost, Moderate Performance
• Less Tacky then SEBS
• Matte Appearance, Opaque Only
• High Heat Resistance
• Low Compression Set
• Chemical Resistance (Hydrocarbons)
• Limited Food Contact and Biocompatible Grades
TPU (Thermoplastic Polyurethane)
• Aromatic, Aliphatic, Polyester, and Polyether Chemistries
• Moderate to High Cost, High Performance
• Excellent Toughness
• Excellent Abrasion Resistance
• Excellent Cut and Tear Strength
• Good Compression Set
• Glossy, Clear, Translucent, Opaque
• Food Contact, Biocompatible, UL Listed, and NSF Approved Grades
MPR (Melt-Processible Rubber)
• Blend of COPE, Chlorinated Ethylene & Other Proprietary Constituents
• Moderate to High Cost, Moderate to High Performance
• Low Squeak
• Good Abrasion Resistance
• Good Chemical Resistance
• Excellent Weather-Ability and Environmental Resistance
• Maintain Flexibility Over Wide Temperature Range
• Matte, Clear, Translucent and Opaque
• High Cost, High Performance
• Tough / Resilient / Repeated Flexures
• Creep and Kink Resistant
• Flexible in Low Temperatures
• Excellent High-Temperature Performance
• Good Resistant to Chemicals, Oils, and Solvents
• Glossy, Opaque
PEBA (Polyether Block Amide)
• Nylon Based Elastomer
• High Cost, High Performance
• Good Low-Temperature Flexibility and Impact Resistance
• Excellent Dynamic Properties (Resilience, Hysteresis, Repeated Flexures, Flex Fatigue Resistance, Kink Resistance)
• Excellent Hydrolytic Stability
• Low Coefficient of Friction
• Glossy, Opaque
How do I go about selecting the proper TPE for my application?
To select the optimal TPE in a specific application, one must consider the following:
Physical and Mechanical Property Requirements
Prioritization considerations are hardness, stretch/bounce back, compression set, abrasion/wear/cut/tear resistance, resistance to bending, adhesion to substrates, energy absorption, acoustic dampening, and any reinforcements or enhancements.
Aesthetic and Appearance Requirements
Surface feel considerations are high surface friction or tacky to touch, dry or silicone-like feel, or silky smooth or lubricious. Surface finish options are glossy or matte, and color options are transparent, translucent, opaque or pre-colored.
Temperature Requirement Considerations: What are the minimum and maximum constant use temperatures, and the length of time exposed to extreme temperatures? UV Exposure and Weather Conditions: Indoors or outdoors, permanent or intermittent?
Chemical Resistance Considerations: Splash exposure or submerged, the temperature during exposure, and chemical types (acid, base, fuel, oil, cleaning solution, etc.)? Load and Flex Issues: Will the part be under pressure, and if so how much, or will it be repeatedly flexed or extended?
Many applications require the TPE to be certified by a regulatory agency or need some form of OEM approval. The most common are REACH SVHC and RoHS compliance, UL certification (flammability and weather-ability), OEM automotive approvals, FDA and EU food contact compliance, FDA toy safety compliance, Medical ISO 10993 or USP Class VI compliance, and NSF 51 and 61 compliance.
Manufacturing Process Method
Options are injection molding, extrusion, blow molding, over-molding, co-extrusion, blown film and calendaring.
Must balance material cost and performance.
How may we assist you today?
Amco Polymers offers a broad range of TPE technologies and products to suit a wide variety of purposes and applications.
The world of polymers continues to grow and offers many design, cost and performance advantages to choose from. Let Amco help you today with our experience in selecting the right material for your application at a cost effective price. Amco Polymers – The Clear Choice in Resin Distribution