Four small details tell you the difference between TPE and TPU.
Source：德创化工Time：2020-04-20Hits：3327
TPE and TPU are thermoplastic materials with rubber elasticity. TPE and TPU materials with similar hardness, especially black, have certain softness and rubber elasticity. It is sometimes difficult to distinguish TPE from TPU if only observed by naked eyes. However, from the details, the differences and differences between TPE and TPU can be analyzed from many aspects.
Difference in hardness (range)
SEBS-modified TPE has a wide range of adjustable hardness, and its hardness range can vary from Shorea Scale 0 to 100, while TPU hardness range is usually from Shore 60A to Shore 70D (soft TPU with hardness of about 45A appears abroad at present, but the price is quite expensive). Therefore, it can be said that TPE hardness range is medium and low hardness, while TPU hardness is medium and high hardness.
Combustion distinction
TPE burns with a special aromatic smell accompanied by petroleum smell (petroleum smell is the burning smell of PP component), the flame tip is yellow, and the flame root is blue (ultra-soft hardness TPE, flame root is yellow). TPU burns with a certain irritating peculiar smell, and there is a slight explosion when burning.
Performance difference
TPU is superior to TPE in elasticity and elastic recovery (bending resistance and creep resistance). TPU is mainly composed of polymer homogeneous structure and belongs to polymer resin. TPE is an alloy material with multiphase structure aggregation formed by multi-component blending. TPE with high hardness is easy to deform, while TPU shows excellent elasticity in all hardness ranges and the product is not easy to deform.
Differences in tactility
Some overmolded products, such as handles and wheels, may be TPE or TPU. TPU products have rough hand feeling and strong friction resistance. TPE products, on the other hand, are delicate and soft to the touch and have weak friction performance.
To sum up, TPE and TPU are both soft materials with good rubber elasticity. Compared with TPE, TPE is more excellent in tactile comfort and TPU is more excellent in elasticity and strength. For products with lower hardness (e.g. less than 30A), TPE should be selected to achieve the effect of skid resistance, shock absorption and rebound. For products with higher hardness (above 80A) and good elasticity, TPU can be competent.
TPE shrinkage is 1.2-3%; TPU shrinkage is 0.8-1.8%. The specific value depends on different brands. Generally, TPU has higher hardness and smaller shrinkage, while TPE has higher hardness and smaller shrinkage.
