Thermoplastic Elastomers (TPEs)

What is Thermoplastic Elastomer (TPE)?
Thermoplastic elastomers (TPEs), also known as thermoplastic rubber (TPR) are high molecule materials which contain features of vulcanized rubber at normal temperature and plastics when heated. It means that once thermoplastic elastomers compounds are formed, they can be heated and reformed repeatedly. The ability of thermoplastic elastomers to process like thermoplastics and imitate the performance and feel of thermoset rubbers has made them stars among plastic materials over a long time.
Thermoplastic elastomers compounds are formed by physical cross-linking of hard phase (plastics) and soft phase (elastomers) materials. This physical cross-linking is reversible which indicates that the molecules are free of flowing at high temperature and regain their original structure and stability at room temperature. This property allows for easy process and facilitates recycling.

Many thermoplastic elastomers (TPEs) families are available in the market. They can be classified as:
1) Styrenic Block Copolymers (SBC, TPS or TPE-S)
2) Thermoplastic Polyurethanes (TPU)
3) Thermoplastic Copolyester / Thermoplastic Polyester Elastomer (TPEE or TPE-E)
4) Thermoplastic Copolyamide / Thermoplastic Amide Elastomer (TPA)
5) Thermoplastic Polyolefin (TPO)
6) Thermoplastic Vulcanizate (TPV)

General features of TPEs:
1) Capable of applying standard plastic processing method, like injection, extrusion, and blow molding.
2) No vulcanization is needed. Energy saving, reducing cycle time, and increasing production efficiency.
3) 100% recyclable and environmental-friendly
4) Good brittle temperature
5) Rubber like texture and feel
6) Lightweight

TPEs Applications:
Speedier processing and lower scrap rates have earned TPEs market niches that continues to expand in consumer, medical, automotive, constructions and buildings, and electronics. Through customized design according to actual requirements can demonstrate various feel, performance, color and as well reduce the system cost. Advantages over synthetic rubber such as recyclability, greater ease of processing and design flexibility are likely to ensure the continued penetration of TPEs in various applications.

Thermoplastic elastomer compounds manufactured by Phon Tech are sold under the trademark PHOENIX™. It is fabricated by the highly praised underwater pelletizer system. PHOENIX™ falls in the category of Styrenic Block Copolymers (SBC).
What is Styrenic thermoplastic elastomer (TPS, TPE-S)?
Styrenic thermoplastic elastomer (TPS, TPE-S) also known as Styrenic Block Copolymers (SBC) are usually described as SBS or SEBS based compounds. They are tri-blocks copolymers containing an elastomeric midblock and polystyrene endblocks. The rubber midblock is typically a polydiene (either polybutadiene or polyisoprene), resulting in the well-known families of SBS and SIS polymers. These products are the first generation of styrenic block copolymers and discovered by Shell Chemical in 1950s.

To improve thermo-oxidative and UV stability, the polybutadiene or polyisoprene rubber block of an SBS or SIS polymer can be hydrogenated to form a styrene-ethylene-butylene-styrene block copolymer (SEBS) or a styrene-ethylene-propylene-styrene block copolymer (SEPS). The double-bonds of SBS which are vulnerable to external influence are then broken. The SEBS polymers demonstrate excellent weatherability, thermal stability and high tensile strength, as well as the characteristics of a non-polar olefinic mid-block. These products are known as second generation of SBC. PHOENIX™ of Phon Tech are compounds mostly based of SEBS or SEPS polymers, some based of SBS polymers.

General features of TPS:
TPS can be considered as the merge of rubber and plastic together. They have the most similar characteristics with rubber. Compare with other TPEs, TPS have the strength of softness, elasticity and less deformation. SBC compounds have general features as below.
Easy to process and color
Excellent UV stability
Excellent weatherability
Ozone resistance
Excellent tensile and tear strength
Good compression and permanent set
Resistant to acid, base, alcohol

TPS Applications:
TPS are the most commonly used thermoplastic elastomer among TPEs. The SBS based TPS are commonly used for those applications that don’t need high specifications, such as shoe outsoles and hand tools grips. While SEBS based TPS show excellent physical properties and superior chemical resistance after being hydrogenated, make them have more design flexibility that can cater customers’ requirements. With superior UV stability and ozone resistance, TPS are ideal for outdoor applications. To sum up, TPS can be used in various markets and industries.
What is Thermoplastic Polyurethanes (TPU)?
Thermoplastic Polyurethane (TPU) is a highly versatile elastomer with unique properties that offers both superior performance and processing flexibility. TPU is generalized in the category of polyurethane plastics. Technically, TPU are thermoplastic elastomers consisting of linear segmented block copolymers composed of hard and soft segments. There are numerous thermoplastic polyurethanes (TPU) in markets, vary with different composition of categories and percentages of diisocyanate (hard segments) and diols (soft segments). They can be used as a soft engineering plastic or as a replacement for hard rubber like PVC.

General features of TPU:
Excellent abrasion / wear resistance
Outstanding impact resistance
Superior toughness & durability
Excellent mechanical properties
Rubber-like high elasticity
Outstanding flexibility performance in low temperature
Good resistance to oil, grease and many solvents
High elongation and tensile strength
High transparency

TPU Applications:
Castor wheels
Hose and tube
Power tools
TPU Coated Fabrics
Wire and Cable Coatings
Sports equipment
Flexible Tubing
What is Thermoplastic Polyester Elastomer (TPE-E or TPEE)?
Thermoplastic polyester elastomer (TPE-E or TPEE), also known as thermoplastic Copolyester, are a class of multiblock copolymers or a physical mix of polymers (usually a plastic and a rubber) which consist of materials with both thermoplastic and elastomeric properties. Thermoplastic elastomers show both advantages typical of rubbery and plastic materials. The principal difference between thermoset elastomers and thermoplastic elastomers is the type of crosslinking bond in their structures. In fact, crosslinking is a critical structural factor which contributes to impart high elastic properties. The crosslink in thermoset polymers is a covalent bond created during the vulcanization process. On the other hand the crosslink in thermoplastic elastomer polymers is a weaker dipole or hydrogen bond or takes place in one of the phases of the material.

General features of TPEE:
Excellent fatigue resistance
Good resilience
Highest heat resistance
Tough, wear resistant
Good tensile strength
Oil/chemical resistant
High impact resistance
Good mechanical properties

TPEE Applications:
Compared with other TPEs, Thermoplastic polyester elastomers (TPEE) exhibits excellent anti-fatigue properties. They show high-temperature resistance up to 140℃ and excellent tear strength. Their features make them ideal for blow molding applications, such as extrusions and industrial tubes. With superior properties, TPEE usually cost high.
TPEE can be used on many kinds of automotive parts, hoses/hard tubes, all kinds of gears, bearings, sealing materials, pipes, cables, communication cables, compression springs, sporting films, golf ball surfaces, etc.
What is Thermoplastic Amide Elastomer (TPA)?
Thermoplastic polyamide (TPA, TPE-A), also known as thermoplastic Copolyamide, comprises hard segments (polyamides) and soft segments (polyethers or polyesters). Thermoplastic Polyamides (TPA) are high performance thermoplastic elastomer (TPE) block copolymers, usually used and classed as engineering material because of their unique combination of properties: great resilience, heat and oil resistance, and high impact at low temperature. In addition, TPA can be processed by usual melt-processing techniques, such as injection molding, extrusion, blow molding.

General features of TPA:
High performance engineering TPE
Wide range of hardness
High impact

TPA Applications:
Because of their toughness over wide range of temperatures, Thermoplastic polyamide (TPA) is considered as important engineering plastics. TPA is mainly used for sport goods, automotive and industrial parts. Due to its high impact at low temperature, TPA occupies a prominent place within the ski equipment market.
What is Thermoplastic Polyolefin (TPO)?
Thermoplastic Polyolefin (TPO) is the compound comprises polypropylene (PP) as hard segments and EPDM as soft segments. Compared with other TPEs families, TPO (thermoplastic polyolefin) has lower specific gravity. TPO also has excellent heat resistance, which is second only to TPEE among TPE families.

General features of TPO:
Low density
Weather resistance
Heat resistance
Ozone resistance
UV resistance
High impact resistance
Good chemical resistance to acid, base and detergent
Flexible at low temperature
Good tear resistance

TPO Applications:
Thermoplastic Polyolefin (TPO) is widely used in different industries. However, it is mainly used in automotive industry of auto parts. And due to its excellent weather resistant, Thermoplastic Polyolefin (TPO) is ideal for outdoor applications.
What is Thermoplastic Vulcanizate (TPV)?
Thermoplastic Vulcanizate (TPV), also known as elastomeric alloy (EA), is classified as polyolefin thermoplastic elastomer family. TPVs are usually the combinations of polyolefin (Polypropylene or Polyethylene) and elastomer (SBR, NR, EPDM, NBR or Butyl). They vary with different composition of hard and soft segments. Most of the TPVs are compounds of PP and EPDM rubber.

TPV is produced in a reactive compounding process. During the dynamic vulcanization process of TPV production, completely cured elastomer particles (micron size crosslinked elastomer particles) homogenously distributed in a continuous matrix of polyolefin. This gives TPV compounds unique rubber-like properties, with the advantage of thermoplastic processing techniques.

TPV Features:
Resistance to chemicals and weathering
Acid, alkali, hydrolysis resistant and exhibit greater oil resistance than other TPEs
Good weather resistance.
Good anti-aging and anti-ozone properties.
Low compression set
The lowest compression set of any other thermoplastic elastomer
Flex fatigue resistance
Soft flexible touch with good fatigue and energy damping properties
High Resilience
Excellent tensile strength, tear strength and resilience
Clean scrap can be recycled and maintain over 95% of property even when recycled up to 5 times
Easy to process, no vulcanized is needed
Can be processed by injection, extrusion and blow molding
Heat resistant up to 135℃, sustain temperature ranges from - 40℃ to 135℃

TPV Applications:
TPV is mainly used in automotive industry, such as CVJ boots air bag cover.
And with its melt flow ability, it also used for building and construction, such as glazing seal, weather strip.