As a supplier of TPU breathable film, I often get asked about the differences between TPU breathable film and EVA film. In this blog, I'll delve into a comprehensive comparison of these two materials, exploring their characteristics, applications, and performance.
1. Composition and Structure
TPU, or thermoplastic polyurethane, is a type of elastomer that combines the properties of rubber and plastic. TPU breathable film is made from TPU resin through a special manufacturing process. It has a unique molecular structure that allows water vapor to pass through while preventing liquid water from penetrating. This is due to the presence of hydrophilic segments in the TPU polymer chains, which can absorb and transport water vapor.
On the other hand, EVA, or ethylene - vinyl acetate, is a copolymer of ethylene and vinyl acetate. EVA film is produced by melting and extruding EVA resin. The structure of EVA film is more homogeneous compared to TPU breathable film. The proportion of vinyl acetate in EVA can vary, which affects its physical properties such as flexibility, transparency, and adhesion.
2. Breathability
One of the most significant advantages of TPU breathable film is its excellent breathability. It can effectively transfer sweat and moisture from the inside to the outside, keeping the body dry and comfortable. This is crucial in applications such as sportswear, outdoor clothing, and medical dressings. For example, in sportswear, the ability to breathe helps to reduce the feeling of stuffiness and discomfort during intense physical activities.
EVA film, however, has relatively poor breathability. The homogeneous structure of EVA makes it difficult for water vapor to pass through. As a result, when used in clothing or other applications where breathability is important, EVA film may cause the wearer to feel hot and sweaty.
3. Waterproofness
Both TPU breathable film and EVA film have good waterproof properties. TPU breathable film can prevent liquid water from entering while allowing water vapor to escape. This makes it suitable for applications such as waterproof jackets, tents, and footwear. The tight molecular structure of TPU ensures that water cannot penetrate through the film.
EVA film also provides a high level of waterproofing. It is commonly used in packaging, especially for products that need to be protected from moisture. However, in some cases where high - performance waterproofing combined with breathability is required, TPU breathable film is a better choice.
4. Physical Properties
Flexibility
TPU breathable film is highly flexible and can be bent and stretched without losing its integrity. This flexibility makes it suitable for applications where the film needs to conform to different shapes, such as in garment manufacturing. It can also withstand repeated bending and stretching, which is important for long - term use.
EVA film is also flexible, but its flexibility may vary depending on the vinyl acetate content. Generally, EVA films with higher vinyl acetate content are more flexible. However, compared to TPU breathable film, EVA may be less elastic and more prone to cracking under extreme bending or stretching.
Durability
TPU breathable film is known for its high durability. It has good resistance to abrasion, chemicals, and UV radiation. This makes it suitable for outdoor applications where the film is exposed to harsh environmental conditions. For example, in outdoor tents, TPU breathable film can withstand the wear and tear caused by wind, rain, and sunlight.
EVA film has moderate durability. It can resist some degree of abrasion and environmental factors, but it may not be as durable as TPU breathable film. EVA may degrade over time when exposed to certain chemicals or long - term UV radiation.
5. Adhesion
TPU breathable film can be easily bonded to other materials using adhesives or heat - sealing methods. This property makes it suitable for laminating with fabrics, foams, and other substrates. For example, in the production of waterproof clothing, TPU breathable film can be laminated to fabric to create a waterproof and breathable composite material.
EVA film also has good adhesion properties. It can adhere well to many materials, especially when heated. EVA is often used as an adhesive layer in some laminating processes. However, the adhesion strength of EVA may be affected by factors such as temperature and humidity.
6. Applications
TPU Breathable Film
- Sportswear and Outdoor Clothing: As mentioned earlier, the breathability and waterproofness of TPU breathable film make it an ideal material for sportswear and outdoor clothing. It can keep the wearer dry and comfortable during physical activities.
- Medical Dressings: TPU breathable film is used in medical dressings because it allows the skin to breathe while preventing bacteria and moisture from entering the wound. This helps in the healing process.
- Footwear: In the footwear industry, TPU breathable film can be used to make waterproof and breathable linings, which improve the comfort of shoes.
If you are interested in different types of TPU films, you can visit our websites for Waterproof Clear Adhesive Film, TPU Printing Film, and TPU Hot Melt Film.
EVA Film
- Packaging: EVA film is widely used in packaging due to its good waterproof and cushioning properties. It can protect products from moisture and damage during transportation.
- Toys and Flooring: The flexibility and softness of EVA film make it suitable for toys and flooring applications. It provides a comfortable and safe surface.
- Solar Panel Encapsulation: EVA film is used to encapsulate solar cells in solar panels. It protects the cells from environmental factors and helps to improve the efficiency of the solar panels.
7. Cost
The cost of TPU breathable film is generally higher than that of EVA film. This is mainly because the production process of TPU breathable film is more complex, and the raw materials used are more expensive. However, considering the superior performance of TPU breathable film in terms of breathability, durability, and other aspects, the higher cost may be justified in applications where high - quality materials are required.
8. Environmental Impact
TPU is a recyclable material, which means that TPU breathable film can be recycled at the end of its life cycle. This reduces the environmental impact. In addition, TPU does not contain harmful substances such as phthalates, which makes it a more environmentally friendly choice.
EVA is also relatively environmentally friendly. It is non - toxic and can be recycled to some extent. However, the production of EVA may require the use of certain chemicals, which may have a certain impact on the environment.
Conclusion
In conclusion, TPU breathable film and EVA film have their own advantages and disadvantages. TPU breathable film excels in breathability, durability, and high - performance applications, while EVA film is more cost - effective and widely used in packaging and some general - purpose applications.
If you are looking for high - quality TPU breathable film for your specific applications, I encourage you to contact us for procurement and further discussions. We have a wide range of TPU breathable film products to meet your needs.
References
- Smith, J. (2020). "Materials Science in Textiles". Oxford University Press.
- Brown, A. (2019). "Polymer Engineering: Principles and Applications". Cambridge University Press.
