Limitations of PP Synthetic Paper in Food Packaging Applications

While PP synthetic paper has advantages like waterproofness and durability, it faces several limitations when used in food packaging, which restrict its scope in this field. These constraints mainly relate to material properties, safety compliance, and practical usability.​

First, heat resistance constraints are a key issue. PP synthetic paper has a relatively low melting point (around 160-170°C). When in direct contact with hot food (e.g., freshly cooked meals, hot beverages above 60°C) or used in high-temperature processing (such as microwave heating or hot filling), it may soften, deform, or even release small molecules. This makes it unsuitable for packaging that requires heat resistance, unlike heat-stable materials like glass or high-temperature-resistant plastics (e.g., PET, PP film for hot filling). For example, it cannot replace microwave-safe containers or packaging for hot soups.​

Second, barrier property deficiencies limit its use for certain foods. While PP synthetic paper is waterproof, its barrier to gases (e.g., oxygen, carbon dioxide) and oils is weak. For foods that need long-term freshness or oil resistance—such as fried snacks, meat products, or baked goods—PP synthetic paper alone cannot prevent oxidation, moisture loss, or oil penetration. This means it often requires additional coating or lamination (e.g., with aluminum foil or barrier films) to enhance its barrier performance. Without such treatments, it cannot replace materials like laminated plastic films or aluminum-plated paper in preserving perishable or oil-rich foods, increasing production costs and complexity.​

Third, strict food safety compliance requirements pose challenges. Different regions (e.g., the EU, the US, China) have strict regulations on food contact materials, requiring them to be non-toxic and free of harmful substances (e.g., heavy metals, plasticizers). While pure PP is generally recognized as safe (GRAS) for food contact, PP synthetic paper may contain additives (e.g., for improving printability or flexibility) during production. If these additives do not meet food safety standards, they could migrate into food, especially under conditions like high temperature or acidic/alkaline environments (e.g., packaging for pickled foods or citrus fruits). This means manufacturers must invest more in testing and selecting food-grade additives, raising production costs and creating compliance risks if not managed properly.​

Fourth, cost and usability issues affect its popularity. Compared to traditional food packaging materials like kraft paper or thin PE films, PP synthetic paper has a higher initial cost. For low-cost, disposable food packaging (e.g., fast-food wrappers, candy wrappers), its higher price makes it less competitive. Additionally, its stiffness (compared to soft PE films) makes it less suitable for packaging irregularly shaped foods (e.g., soft pastries, fresh fruits), as it cannot conform to the food’s shape well, reducing user convenience and packaging tightness.