1、硬度（范围）的差异 基于SEBS改性的TPE具有广泛可调整的硬度，其硬度范围可以在Shore A Scale 0~100范围变动，而TPU硬度范围则通常是在Shore 60A~Shore70D(目前国外出现硬度在45A左右的软性TPU,不过价格相当昂贵）。因此，可以说TPE的硬度区间是中低硬度，而TPU硬度则是中高硬度。
TPE is based on SEBS modification. TPU refers to thermoplastic polyurethane. TPE and TPU are rubber elastic materials with thermal plasticity. TPE and TPU materials with similar hardness, especially black, have certain softness and rubber elasticity. For example, it is difficult to distinguish TPE or TPU only by naked eyes. But starting from the details, we can analyze the differences between TPE and TPU from many aspects.
1. The difference of hardness (range) is based on the widely adjustable hardness of SEBS modified TPE. The hardness range of TPE can be changed from shore a scale 0 to 100, while the hardness range of TPU is usually from shore 60A to shore 70D (soft TPU with hardness of about 45A appears in foreign countries, but its price is quite expensive). Therefore, it can be said that the hardness range of TPE is medium to low hardness, while that of TPU is medium to high hardness.
2. TPE combustion is distinguished by combustion. The odor is special aromatic with petroleum odor (petroleum odor is the combustion odor of PP component), the flame tip is yellow, and the flame root is blue (super soft hardness TPE, and the flame root is yellow). TPU combustion has a certain irritating odor, and there is a slight explosion sound of zzz during combustion.
3. The elastic and elastic recovery properties of TPU are better than that of TPE. The main reason is that the material structure of TPU is polymer homogeneous structure, which belongs to polymer resin. TPE is a kind of alloy material with multi-component blending and multi-phase structure aggregation. High hardness TPE processing is prone to product deformation, and in all hardness ranges, TPU shows excellent elasticity, and the product is not easy to deformation.
4. Tactile differences some products, such as handles and wheels, may be TPE or TPU. TPU products have rough hand feel and strong friction resistance, while TPE products have delicate and soft hand feel and weak friction performance.
In conclusion, TPE and TPU are soft materials with good rubber elasticity. Compared with TPE, TPE is more excellent in tactile comfort, TPU is more excellent in elasticity and strength. For products with lower hardness (such as below 30a), TPE should be selected, which can play a role of antiskid, buffer, shock absorption and rebound. For products with high hardness (above 80A) and good elasticity, TPU is competent. The shrinkage of TPE is 1.2-3%, and that of TPU is 0.8-1.8%.