What types of TPE materials are there?

In fact, the Chinese name of TPE is thermoplastic elastomer, also known as thermoplastic rubber. It is a material that can be directly processed and molded without vulcanization, and has rubber elasticity. Currently, domestic TPE manufacturers are mainly divided into styrene-based thermoplastic elastomer SBS, thermoplastic polyurethane TPU, thermoplastic polyolefin elastomer TPO, polyester elastomer TPEE, etc. Next, let's take a look at the differences between these types!

1. Thermoplastic polyester elastomer TPEE
TPEE (thermoplastic polyester elastomer) is a block copolymer containing polyester hard segments and polyether soft segments. TPEE has the elasticity of rubber and the strength of engineering plastics; the soft segments give it elasticity, making it like rubber, and the hard segments give it processability, making it like plastic. Compared with rubber, it has better processing performance and longer service life; compared with engineering materials, it also has high strength, but better flexibility and dynamic mechanical properties. TPEE can withstand low and high temperatures, and can be used for a long time under conditions of -40 to 160°C. TPE has excellent chemical resistance, weather resistance and aging resistance. It is mainly used where shock absorption, impact resistance, flex resistance, sealing and elasticity, oil resistance, chemical resistance and sufficient strength are required. Such as: polymer modification, automotive parts, high and low temperature resistant wire sheaths, hydraulic hoses, shoe materials, transmission belts, rotomolded tires, flexible couplings, sound absorption, elevator slides, anti-corrosion, wear-resistant, high and low temperature resistant materials, etc.

2. TPU

TPU is made by blending polypropylene PP and ethylene propylene diene monomer rubber (EPDM). During the blending process, EPDM rubber is distributed as a dispersed phase in the PP continuous phase. At the same time, during the blending of PP and EPDM, EPDM itself begins to vulcanize, and this process is called dynamic vulcanization. The self-vulcanization of EPDM does not affect the injection molding of TPV because EPDM exists as a dispersed phase; on the contrary, the presence of vulcanized cross-linked EPDM enhances the wear resistance, strength, and acid/alkali corrosion resistance of TPV, etc.

3. SBS

SBS includes styrene-butadiene block copolymer SBS and its hydrogenated polymer SEBS, as well as modified materials of SBS and SEBS: TPS and TPES (Some in the elastomer industry call TPS TPR, and TPES is also called TPE in the elastomer industry, which is different from the general scope of TPE materials). SEBS and SBS elastomers are mostly used for polymer material modification, toughening, and tackifying resins for adhesives, coatings, and inks, while SEBS and SBS modified materials, TPES, TPS, etc. have more flexible and diverse physical properties and hardness, and are therefore widely used in toys, daily necessities, sports and fitness products, automotive supplies, medical devices, shoe materials, wire and cable industries. Because of this, the consumption of styrene-based thermoplastic elastomers is the largest among all TPEs worldwide.

4. TPO

TPO is composed of rubber and polyolefin. Usually, the rubber component is ethylene propylene diene monomer (EPDM), nitrile butadiene rubber (NBR), and butyl rubber; the polyolefin component is mainly polypropylene (PP) and polyethylene (PE). TPO has become the main rubber-plastic material for automobiles and home appliances, with automotive consumption accounting for more than 75% of total output. It is the fastest-growing variety of TPE.