When choosing eco-friendly packaging products, many consumers wonder: as a replacement for traditional plastic bags, can biodegradable bags meet the load-bearing and tear-resistant requirements in daily use? In fact, with the continuous advancement of material technology, today’s biodegradable bags already possess good tensile properties. They can not only adapt to various item packaging scenarios but also effectively avoid easy tearing, truly achieving a dual balance between “environmental protection” and “practicality”.
From the perspective of material composition, the tensile properties of biodegradable bags stem from scientific formula design. Although their main raw materials are dominated by natural degradable components such as corn starch and plant fibers, biodegradable polymer materials like PLA (Polylactic Acid) and PBAT (Polybutylene Adipate Terephthalate) are added during the production process for modification. These polymer materials have excellent ductility and toughness, and can form a stable structural network at the molecular level. When the bag is pulled by external forces, the molecular chains can disperse stress through moderate deformation, preventing breakage caused by excessive local stress. For example, biodegradable bags with PBAT as the main component have an elongation at break of over 500%. Even when stretched to several times their original length, they are not prone to cracks. This performance can already meet the tensile needs of most daily packaging scenarios.
In practical application scenarios, the tensile properties of biodegradable bags can adapt to diverse usage needs. Whether it is for holding fruits, vegetables, rice, flour, grain, or oil during supermarket shopping, or for storing items such as clothes and books at home, they can fit the shape of the items with their good tensile properties while bearing a certain weight. Taking the common biodegradable shopping bag with a thickness of 0.025mm as an example, its transverse tensile strength can reach more than 15MPa, and its longitudinal tensile strength can reach more than 18MPa. It can easily carry items weighing 5-8 kilograms, and during carrying, the bag mouth and handle are not prone to damage due to stretching. Even when encountering items with obvious edges and corners (such as boxed milk and bottled beverages), the bag can wrap the edges of the items through local stretching, avoiding tearing caused by friction or extrusion.
Compared with traditional plastic bags, although the tensile properties of biodegradable bags are slightly inferior in extreme scenarios (such as long-term exposure to overweight loads and repeated severe pulling), they have fully covered the core needs of daily use and have an irreplaceable advantage in “environmental friendliness”. Traditional plastic bags have higher tensile strength but are difficult to degrade, causing long-term environmental burdens; while biodegradable bags can gradually decompose in the natural environment without generating “white pollution” while ensuring basic tensile properties. More importantly, some high-end biodegradable bags have achieved tensile properties comparable to traditional PE (Polyethylene) plastic bags by optimizing material ratios (such as adjusting the mixing ratio of PLA and PBAT). For instance, PLA-based biodegradable bags with 30% PBAT added have a tensile strength of up to 20MPa and an elongation at break of up to 400%, which can fully meet scenarios with high tensile property requirements such as express packaging and fresh food transportation.
It should be noted that the tensile properties of biodegradable bags are affected by the usage environment and storage methods. If exposed to high temperatures (exceeding 60℃) or strong light for a long time, the material may age in advance, leading to a decline in tensile properties; if it comes into contact with sharp objects during storage, local damage may also affect the overall tensile effect. Therefore, it is recommended to store biodegradable bags in a cool and dry place, and avoid contact with high-temperature objects or sharp edges during use to give full play to their tensile performance advantages.
Today, biodegradable bags are no longer synonymous with “environmentally friendly but not durable”. Their continuously improved tensile properties allow consumers to practice the concept of environmental protection without sacrificing the user experience. From daily shopping to industrial packaging, biodegradable bags are gradually replacing traditional plastic bags with the support of “reliable tensile properties”, becoming a high-quality choice that balances ecological protection and life convenience. With further breakthroughs in material technology, biodegradable bags will achieve greater progress in tensile properties and durability in the future, injecting more vitality into the eco-friendly packaging industry.
