What are the Differences in Performance Between PVDC Shrink Film and EVOH Film?
When it comes to the global food packaging supply chain, selecting the right materials is crucial in ensuring product freshness, brand reputation, and market access. Among high-barrier packaging solutions, PVDC (Polyvinylidene Chloride) shrink film and EVOH (Ethylene-Vinyl Alcohol Copolymer) film are two prominent options. As global environmental regulations become stricter and supply chains become more localized, material choices now extend beyond technical specifications to include lifecycle costs and compliance risks.
EVOH offers an exceptional oxygen barrier, with oxygen transmission rates as low as 3 cm³/(m²·24h·0.1MPa), making it a top choice for oxygen-sensitive products like premium nuts and health snacks. However, this remarkable performance has a significant limitation: it requires a dry environment. When humidity levels rise, EVOH absorbs moisture, significantly diminishing its oxygen barrier capabilities. Because of this, EVOH is typically used as a barrier layer in multi-layer films, combined with moisture-resistant materials like PE or PA. While effective, this approach increases complexity in processing and raises costs.
On the other hand, PVDC film provides a more balanced solution with exceptional oxygen and moisture resistance. One of its key benefits is that its barrier properties are largely unaffected by humidity changes. Whether tested under ASTM F1249 or ISO 15105 standards, PVDC retains its excellent performance even in high-humidity environments. This means that products packaged with PVDC shrink film can enjoy consistent protection, whether stored in humid regions like South America or in dry, cold areas like Russia.
For instance, in a beef shrink-wrap case involving exports to Australia, PVDC film helped extend the shelf life of the product by an average of 30% during long-distance sea transport and throughout various retail conditions. This extension significantly reduced losses caused by oxidation or moisture absorption, demonstrating how PVDC's stable barrier properties can enhance the product's market viability.
Material selection isn't just about lab data—it's also about how the material performs on the production line and throughout the product's lifecycle.
In terms of mechanical and processing performance, PVDC barrier film shines with its high toughness, low-temperature flexibility, and excellent shrink characteristics. These features allow PVDC to conform tightly to product contours when heated, enhancing packaging aesthetics and reducing residual air in the package, which further limits microbial growth. This makes it an ideal choice for automated, high-speed packaging of items like ham, sausages, and cheese. Additionally, PVDC has strong high-temperature resistance, withstanding 125°C for 30 minutes in sterilization conditions.
By contrast, EVOH films have limited mechanical strength and are mainly used as functional layers in composite structures. While EVOH is exceptional in transparency and oil resistance, it is better suited for premium visual packaging rather than high-volume, high-performance applications.
When comparing total cost, PVDC shrink film bags usually provides a clear cost advantage, with material and processing costs typically one-third to one-half those of EVOH multi-layer composite films. This makes PVDC highly cost-effective for large-scale commercial applications requiring superior barrier properties, such as meat products, cheese, and pet food packaging. In contrast, EVOH, with its higher material costs and more complex processing requirements, is usually reserved for high-value applications demanding top-tier oxygen protection, such as certain pharmaceutical packaging and premium health foods.
One of the major advantages of PVDC heat shrink film bags is its environmentally stable barrier properties, which significantly reduce the risk of product loss due to packaging failure. This is particularly important in long-distance international shipping, where products cross multiple climate zones. A single large-scale loss due to packaging failure can outweigh the cost difference between materials. As such, choosing a packaging material is not just about upfront costs—it's about ensuring reliable protection for your products in complex global supply chains, which is a strategic investment in reducing risk.
Not all products require EVOH-level protection. We recommend considering the specific needs of your product. For example, if your product contains high fat content or includes oxygen-sensitive ingredients such as unsaturated fatty acids or vitamins (like premium pet foods or health snacks), and your pricing can absorb the additional packaging cost, then EVOH could be the right choice. However, for many standard items like meat, cheese, or sauces, PVDC shrink wrap bag's all-around stable barrier is typically more than sufficient, providing better cost-effectiveness. A simple experiment, like accelerated shelf-life testing, can help determine which material best meets your needs.
Absolutely. Due to its excellent chemical stability and moisture resistance, PVDC has many uses beyond food packaging. For example, in the pharmaceutical industry, PVDC can be used for moisture-sensitive tablet packaging, and in the industrial sector, it can be used to package precision electronics or chemical products that require moisture and corrosion protection. The shrink characteristics of PVDC allow for tight collective packaging with a strong visual appeal.
Choosing between EVOH and PVDC film isn't a simple decision—there's no one-size-fits-all answer. The smartest choice comes from a comprehensive evaluation of your product's characteristics, the logistics environment, market regulations, and cost structures. When you select packaging materials, you are making a choice that impacts product quality and brand integrity. It's not just about protecting your product, but also about delivering on your brand promise.
