Flexible Packaging Concepts for Enhanced Food Safety

Flexible packaging concept：

In the national standard for general terminology of packaging, packaging is defined as: a general term for containers, materials and auxiliary materials used according to certain technical methods to protect products during circulation, facilitate storage and transportation, and promote sales. Flexible packaging refers to packaging that can change the shape of the container after filling or removing the contents. Various bags, boxes, sleeves, packages, etc. made of paper, aluminum foil, fiber, plastic film and their composites are all flexible packaging

Commonly used materials for flexible packaging

PE (polyethylene)

Introduction: PE is the abbreviation of polyethylene, which is a thermoplastic resin obtained by polymerizing ethylene. Depending on the polymerization method, molecular weight, and chain structure, it can be divided into high-density polyethylene, low-density polyethylene, and linear low-density polyethylene.

Advantages: odorless, non-toxic, excellent low temperature resistance, excellent chemical stability, insoluble in general solvents at room temperature, good water resistance, and excellent electrical insulation properties.

Purpose: As a heat sealing layer, it plays the role of heat sealing and low temperature heat sealing.

PP （polypropylene）：

Introduction: PP is the abbreviation of polypropylene, a thermoplastic resin made from the polymerization of propylene. According to the arrangement position of the methyl groups, it is divided into isotactic polypropylene, atactic polypropylene and syndiotactic polypropylene.

Advantages: pure texture, non-toxic, good mechanical properties, high heat resistance, stable chemical properties, good water resistance, good electrical insulation

Purpose: As a heat sealing layer, it plays a heat sealing role and can withstand high temperatures of 121°C.

PA （Polyamide）：

Introduction: PA is the abbreviation of polyamide, commonly known as nylon. It is the general name for thermoplastic resins containing repeating amide groups on the molecular main chain. The main varieties in PA are nylon 6 and nylon 66.

Advantages: excellent mechanical properties, excellent heat resistance, flame retardant, excellent electrical insulation properties, excellent weather resistance, good oxygen barrier properties, good puncture resistance and oil resistance.

Purpose: As a barrier layer, it plays a blocking role.

EVOH （Ethylene vinyl a lcohol copolymer）：

Introduction: EVOH is the abbreviation of ethylene/vinyl alcohol copolymer. It is a crystalline polymer with a chain molecular structure that combines the processability of ethylene polymer and the barrier effect of vinyl alcohol polymer.

Advantages: non-toxic and odorless, an environmentally friendly material, strong oil resistance and organic solvent resistance, high gas barrier properties, good thermal stability, excellent weather resistance, and transparent and clear.

Purpose: As a barrier layer, it plays a high barrier role.

PET （Polyester）：

Introduction: Polyethylene terephthalate, referred to as PET, is a high polymer derived from the dehydration condensation reaction of ethylene terephthalate. Ethylene terephthalate is obtained by the esterification reaction of terephthalic acid and ethylene glycol.

Advantages: Excellent physical and chemical properties, dimensional stability, transparency, and recyclability. It can be widely used in magnetic recording, photosensitive materials, electronic and electrical insulation, industrial films, packaging decoration and other fields. With the special functional polymer With the development of ester films, new uses are constantly emerging.

Usage: Often used for printing in packaging, it is widely used and can withstand high temperatures.

Modified PE：

Introduction: Various materials that are copolymerized and modified based on PE have more functionality than PE.

Advantages: Different functions are given to materials according to different modification characteristics. Common modified materials are: EAA: copolymerization with acrylic acid, EMAA: copolymerization with methacrylic acid, EVA: copolymerization with vinyl acetate, Surlyn: Sarin, Ionic polymers.

Usage: Used for various packaging purposes with high requirements: such as oil-proof, low-temperature heat sealing, high-speed packaging, etc.

EVA （Ethylene Vinyl Acetate Copolymer）：

Introduction: EVA is the abbreviation of ethylene-vinyl acetate copolymer. EVA is copolymerized by ethylene monomer and vinyl acetate monomer in different proportions. Different proportions determine its performance.

Advantages: Oxidation resistance, good flexibility, good toughness, good chemical stability, good anti-aging and ozone resistance, non-toxic, food contact compliance.

Purpose: As a heat sealing layer, it has low temperature heat sealing effect.

AL foil (Ethylene vinyl alcohol copolymer)：

Introduction: It is a hot stamping material that is directly rolled into thin sheets from metal aluminum. Its hot stamping effect is similar to that of pure silver foil, so it is also called fake silver foil.

Advantages: non-toxic, clean, hygienic, inhibiting the growth of any bacteria or microorganisms on its surface. It has good plasticity, easy tearing effect, good shading effect and excellent barrier properties.

PVDC （polyvinylidene chloride）：

Introduction: PVDC is the abbreviation of polyvinylidene chloride, which is a polymer of vinylidene chloride.

Advantages: excellent barrier properties, stable chemical properties, good heat resistance, excellent weather resistance, good transparency, green and environmentally friendly.

Purpose: As a barrier layer, it has high barrier effect.