This article delves into the key differences between PE foam and EVA foam, analyzing how product hardness affects sealing, cushioning, shock absorption, and durability. It offers insights into hardness testing methods, industry application matching guidelines, and frequently asked questions to assist in making informed decisions when selecting foam materials.
Main Content
1. Manufacturing Process and Hardness Characteristics of PE Foam and EVA Foam
PE Foam (Polyethylene Foam)
- Produced through physical or chemical foaming, primarily featuring a closed-cell structure.
- Typical hardness range: 15-50 Shore C (low density) to 70+ Shore C (high-density cross-linked foam).
- Characteristics: High rigidity, excellent chemical resistance, though slightly lower elasticity compared to EVA.
EVA Foam (Ethylene-Vinyl Acetate Copolymer Foam)
- Manufactured via hot-press molding, combining both open-cell and closed-cell structures.
- Typical hardness range: 30-80 Shore A, customizable from ultra-soft (≤20 Shore A) to ultra-hard (90+ Shore A).
- Characteristics: Exceptional elasticity and tear resistance, widely used in sports equipment and packaging cushioning.
2. Impact of Product Hardness on Core Performance
Sealing Applications
- Low hardness (Shore A 30-50): High compression deformation rate, ideal for irregular surface sealing (e.g., appliance dust seals).
- High hardness (Shore A 70+): Resists permanent deformation, suitable for long-term pressure sealing (e.g., industrial equipment gaskets).
Shock Absorption Applications
- PE Foam (hardness 50-70 Shore C): Ideal for heavy equipment packaging, effectively absorbing impact energy.
- EVA Foam (hardness 55-75 Shore A): Preferred for sneaker midsoles, balancing rebound and energy absorption.
3. How to Test and Select Product Hardness Parameters?
Hardness Testing Methods
- Shore Hardness Tester (Shore A/C standards)
- Dynamic Compression Test (ASTM D395)
- Rebound Rate Test (ISO 8307)
Material Selection Decision Tree
| Application Scenario | Recommended Material | Target Hardness Range |
|---|---|---|
| Child Toy Protective Corners | EVA Foam | Shore A 40-50 |
| Automotive Soundproofing Layer | Cross-linked PE Foam | Shore C 60-75 |
| Yoga Mat Core Layer | EVA Foam | Shore A 55-65 |
FAQ Section
Q1: Which foam is better for long-term outdoor use, PE or EVA?
A: PE foam offers superior UV resistance but requires surface coatings (e.g., waterproof film) for reinforcement. EVA foam has lower outdoor durability and is recommended to be modified with antioxidants.
Q2: Can hardness be adjusted using additives?
A: Yes. Adding calcium carbonate increases EVA hardness (by 10-15 Shore A), while reducing foaming ratio can boost PE hardness by over 20%.
Q3: What is the difference between Shore A and Shore C hardness units?
A: Shore A is used for soft elastomers (e.g., EVA), while Shore C is for harder foams (e.g., high-density PE).
Q4: How to determine if product hardness meets my application needs?
A: Provide the following details for precise recommendations:
- Load-bearing pressure (kPa)
- Environmental temperature range
- Contact medium type (oil/water/chemicals).
WELLE Trade has over 20 years of experience in the production and processing of PE/EVA/TPE foams, so you may want to consult with them if you have any sourcing needs.
