In the entire service life cycle of biodegradable bags, the storage stage is often overlooked. However, as a key influencing factor, ambient temperature is directly related to whether the bags can maintain stable physical properties and degradation characteristics. Many users have the question: “Is there a requirement for the storage environment temperature of biodegradable bags?” The answer is yes. Due to the special physical and chemical properties of their core raw materials (such as PLA and PBAT), the storage temperature must be strictly controlled. If it exceeds the appropriate range, it may cause the bags to age in advance, lose their performance, or even lose their environmental protection function.
From the perspective of material properties, the main components of biodegradable bags—PLA (Polylactic Acid) and PBAT (Polybutylene Adipate Terephthalate)—are extremely sensitive to temperature, which determines the core requirements for their storage temperature. The glass transition temperature of PLA is approximately 60°C. When the ambient temperature approaches or exceeds this value, the molecular chains of PLA will transition from a rigid state to a flexible state, causing the bags to stick together, deform, or even lose their original stiffness. Although PBAT has strong toughness, its softening temperature is about 45°C. Long-term exposure to high-temperature environments will accelerate the oxidative degradation of the material, leading to a significant decrease in the tensile strength and elongation at break of the bags. Conversely, if the temperature is too low (e.g., below 0°C), PLA will become more brittle and prone to breaking; a slight force during handling may cause tearing, affecting normal use.
Based on industry practices and material properties, the suitable storage temperature range for biodegradable bags is 5°C-30°C. Within this range, the molecular structures of PLA and PBAT can remain relatively stable—there will be no premature degradation or sticking caused by high temperatures, nor brittle fracture due to low temperatures. For example, in retail scenarios such as supermarkets and convenience stores, if biodegradable shopping bags are stored in a normal-temperature warehouse (with the temperature controlled at 20°C-25°C), they can maintain good performance for 6-12 months. However, in hot summer, if they are stacked outdoors or placed in a warehouse without air conditioning (where the temperature may exceed 40°C), problems such as surface stickiness and a more than 30% decrease in tensile performance will occur in only 1-2 months, making them unable to meet the load-bearing requirements for shopping.
The hazards of improper storage temperatures to biodegradable bags are mainly reflected in two aspects: First, high temperatures accelerate degradation and failure. When the temperature exceeds 35°C, the ester bonds in the material will break in advance, and the bags will show signs of aging before use, such as yellowing color, fine cracks on the surface, or even sticking together during stacking, which is difficult to separate. At the same time, high temperatures will disrupt the degradation balance of the bags, possibly causing them to lose strength during the service life or fail to decompose completely during the degradation stage. Second, low temperatures damage physical properties. When the temperature is below 0°C, the brittleness of PLA increases significantly, the impact resistance of the bags decreases, and they are prone to damage during transportation or handling. Even if the temperature returns to normal, their elongation at break may not recover to the original level, affecting the user experience.
In addition to temperature, the storage environment also needs to be matched with other conditions to ensure the performance of biodegradable bags. First, direct sunlight should be avoided, as ultraviolet rays will accelerate material aging. Therefore, the bags should be stored in a cool and well-ventilated place, and can be packaged in cartons or plastic boxes with good light-shielding properties. Second, environmental humidity should be controlled—the relative humidity is preferably maintained at 40%-60%. Excessively high humidity may cause the bags to absorb moisture and become moldy, while excessively low humidity may easily make the material brittle. Finally, contact with organic solvents or corrosive substances should be avoided to prevent chemical changes in the material, which may affect its degradability and safety.
In conclusion, there are clear requirements for the storage environment temperature of biodegradable bags, with the suitable range being 5°C-30°C. Scientifically controlling the storage temperature and matching it with reasonable conditions such as humidity and light can not only ensure that the bags maintain good physical properties before use but also guarantee that they decompose completely as expected after use, truly realizing environmental protection value. Whether it is manufacturers, distributors, or consumers, all need to attach importance to the storage stage to avoid resource waste and environmental burden caused by improper storage.
