Sub Zero Polypropylene Grade Selection for Packaging Molders
Heterophasic polypropylene copolymers with controlled rubber dispersion prevent brittle container shattering during sub-zero cold chain transport and drop impact.
Sub Zero Packaging
Meaning
Specialized containers and films designed to maintain their integrity at temperatures well below freezing are essential for the cold chain industry. Developing sub zero packaging requires selecting resins that do not become brittle or lose their seal strength when exposed to extreme cold. These materials are used for frozen food storage, medical transport and outdoor industrial goods.
The application of this term is restricted to packaging that must withstand physical handling while at these low temperatures.
Thermal Stress
Exposure to rapid temperature changes can cause internal stresses in a plastic container. Since sub zero packaging must move from room temperature to a deep freeze, it must be able to contract without cracking. The design of the package often includes rounded corners to distribute these stresses more evenly.
These features prevent the material from failing at its weakest points.
Resin Requirement
Selection of a high impact copolymer or a specialized blend is necessary to meet the demands of the cold. Standard homopolymers are unsuitable because they shatter easily when frozen. A resin used for sub zero packaging must also be food safe and resistant to moisture.
These properties ensure that the contents remain protected from the environment.
Supply Chain
Performance of the package during shipping determines the success of a product in the market. If sub zero packaging fails in a warehouse or on a truck, the entire contents may be lost. Durable materials reduce the risk of leaks and contamination.
Resilient packaging also allows for taller pallets and more efficient transport.