The material of the food packaging film is polyhydroxyalkanoate (PHA), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), and polycarbonate (PC).
First, material selection:
Environmental choices - Polyhydroxyalkanoates (PHA); Food bag options - Polyethylene (PE)
Fresh-keeping choices - Polyvinyl chloride (PVC); Grease food choices - Polypropylene (PP)
Two or five materials introduction:
1. Polyhydroxyalkanoate (PHA) material
It is a biopolymer material, an intracellular polyester synthesized by many microorganisms, and a natural polymer biomaterial.
With biodegradability and hot workability of plastics, materials often have high water vapor transmission, which is disadvantageous in food preservation.
PHA has good gas barrier properties, making it possible to use it in long-term fresh-keeping packaging.
2, polyethylene (PE) material
Good water resistance and moisture resistance, poor resistance to gas barrier organic vapor, good chemical stability, no reaction with common acid and alkali at room temperature, slightly poor oil resistance;
It has certain mechanical tensile and tear strength, good flexibility and low temperature resistance.
3. Polypropylene (PP) materials
The barrier property is better than PE, and the strength, hardness and rigidity are higher than PE;
It is mainly made into film material packaging food, suitable for packaging oily foods.
4, polyvinyl chloride (PVC) materials
Poor thermal stability, poor fluidity in the viscous flow state, need to add plasticizer to improve performance;
Gas barrier, oil resistance, gloss is higher than PE, generally used for fresh fruit and vegetable packaging.
5, polycarbonate (PC) material
It is difficult to dissolve crystals, has good transparency and mechanical properties, and has low impact resistance;
However, it is expensive and can be injection molded into pots, boxes, and blow molded into bottles and cans.