Thermoplastic elastomers (TPEs) are a class of polymers that combine the elasticity of rubber with the processability of plastics. Their molecular structure contains both soft segments (providing flexibility and elasticity) and hard segments (contributing to strength and processability). Through formulation design, TPE hardness can be tailored across a wide range, typically from Shore A0 to Shore D60, allowing them to meet diverse performance requirements in different industries.

1. Low Hardness TPE (Shore A0–A30)

Key Properties:

• Extremely soft and flexible, similar to silicone rubber

• Excellent rebound resilience and skin-friendly touch

• Good transparency and flowability during processing

Typical Applications:

• Medical devices: catheters, tourniquets, oral care products

• Infant products: pacifiers, teething toys, baby-safe items

• Consumer goods: anti-slip mats, soft protective covers, sealing rings

2. Medium Hardness TPE (Shore A30–A70)

Key Properties:

• Balanced softness and mechanical strength

• Comfortable surface feel and excellent fatigue resistance

• Suitable for overmolding with PP, ABS, and other substrates

Typical Applications:

• Automotive: steering wheels, handbrakes, door seals

• Electrical and electronics: cable sheathing, plugs, flexible hoses

• Consumer goods: toothbrush handles, sports grips, kitchen anti-slip parts

3. High Hardness TPE (Shore A70–D20)

Key Properties:

• Higher mechanical strength and abrasion resistance

• Good resilience under heavy load with cost advantages over TPU

• Dimensional stability with reliable long-term durability

Typical Applications:

• Industrial components: vibration dampers, wear-resistant parts

• Automotive parts: floor mats, lighting seals, luggage handles

• Consumer goods: luggage wheels, structural sports equipment parts

4. Ultra-High Hardness TPE (Shore D20–D60)

Key Properties:

• Rigidity approaching engineering plastics while retaining some flexibility

• Excellent dimensional stability and impact resistance

• Surface is easily processable for painting, printing, or plating

Typical Applications:

• Engineering parts: small gears, structural support components

• Electronics: phone cases, tablet stands, rigid overmolded housings

• Construction and sealing: rigid window/door gaskets, protective parts

Technical Summary

Hardness in TPE materials is primarily controlled by adjusting molecular weight, blending ratios, and plasticizer content. Low hardness grades emphasize softness and comfort, medium hardness grades offer balanced tactile feel and support, while high hardness grades provide abrasion resistance and structural integrity.

When selecting TPE for specific applications, manufacturers should consider the final product’s performance requirements—such as hand feel, wear resistance, weatherability, and processing methods—in order to achieve an optimal balance between performance, processability, and cost.