Method for manufacturing biodegradable packaging bags

The production of biodegradable packaging bags begins with selecting suitable raw materials based on the product's intended use. Common materials include PLA, PBAT, starch-based materials, and other biodegradable polymers, each with distinct properties and processing requirements. Before production, raw materials are proportioned and mixed, with appropriate additives incorporated to ensure the material possesses the desired flexibility, strength, and processability. Once the raw materials are prepared, they are heated to a state suitable for processing.

 

Biodegradable packaging bags are typically manufactured by producing film via methods such as blown film extrusion or cast film extrusion. Taking the blown film process as an example, the blended raw materials enter an extruder and melt at a specific temperature; the melt is then extruded through a die to form a tubular film, which is inflated with air and subsequently cooled to create a continuous film. After formation, the film undergoes hauling and winding, with thickness and width controlled according to product specifications. For high-performance packaging, multi-layer co-extrusion may be employed to combine different materials, thereby enhancing the film's strength, water resistance, and sealing properties.

 

Subsequent processing steps include printing, bag making, and heat sealing. Depending on usage requirements, product names, patterns, and brand logos can be printed on the film surface before it is cut to the specified dimensions. The cut film is sealed at the edges using heat-sealing equipment, and features such as handles or closure mechanisms are added as needed. Throughout this process, parameters such as heat-sealing temperature, pressure, and duration must be carefully controlled to prevent issues like weak seals or film deformation.

 

Quality checks are performed on the bags, covering dimensions, appearance, thickness, seal strength, and load-bearing capacity. For products intended for food packaging, compliance with relevant safety standards is also verified. Once approved, the bags are organized and packaged according to specifications, then stored in a dry, well-ventilated environment away from direct sunlight. By effectively managing stages such as raw material selection, forming, printing, and bag making, the overall quality of the biodegradable packaging bags can be optimized to meet practical application needs.