Film blowing is a primary process for manufacturing plastic films. However, the performance of pure plastic resin is limited and often fails to meet the demands of complex practical applications. This is where various functional additives play a critical role. They act like "vitamins" and "modifiers" for the film, significantly enhancing its quality and expanding its range of applications.
Firstly, stabilizing additives are the foundation for a long-lasting film. During high-temperature processing and subsequent exposure to sunlight, plastics are prone to degradation, leading to embrittlement, discoloration, and loss of strength. Antioxidants effectively suppress thermal oxidation during processing, ensuring smooth production. Anti-UV agents, on the other hand, protect against UV radiation, delaying aging and significantly extending the film's service life.
Secondly, surface property additives directly impact the user experience. Slip agents reduce the coefficient of friction on the film's surface, making film bags easier to open and improving the efficiency of bag-making and packaging processes. Anti-blocking agents prevent film layers or rolls from sticking together due to pressure and heat, ensuring the film can be unwound smoothly and evenly, avoiding waste.
Furthermore, there are specialized additives for particular fields. For instance, antifogging agents are essential in fresh food packaging. They prevent the formation of fine water droplets on the inner film surface caused by temperature differences, maintaining clarity and an appealing appearance. This allows consumers to see the contents clearly and prevents water droplets from promoting mold growth and contaminating the food.
In summary, functional additives are indispensable components in modern film blowing technology. Through scientific formulation and selection of appropriate additives, manufacturers can precisely control various film properties—such as weather resistance, slip, and clarity—thereby transforming basic plastic resin into high-performance packaging materials capable of meeting diverse and complex requirements.