How to achieve the barrier properties of vinyl acetate in food packaging films such as EVOH?

How to achieve the barrier characteristics of vinyl acetate in food packaging films such as EVOH?

With the continuous improvement of food preservation and packaging material performance standards, the barrier performance of food packaging film has have become the focus of attention. Among them, the consumption of vinyl acetate in EVOH (ethylene-vinyl alcohol copolymer) materials is favored due to its excellent barrier characteristics. This article will examine in detail how the barrier characteristics of vinyl acetate in EVOH are achieved.

1. And Vinyl acetate and EVOH relationship

EVOH is an ethylene-vinyl alcohol copolymer, and its molecular structure includes an ethylene segment and a vinyl alcohol segment. Among them, the ethylene chain segment provides thermoplastic and processing characteristics of the material, while the vinyl alcohol chain segment gives the material excellent barrier characteristics. Vinyl acetate plays an crucial role in the formation of EVOH, because it's able to be converted into vinyl alcohol through chemical interaction, and then participate in the copolymerization interaction to create EVOH. This structural feature makes EVOH have good gaseous barrier characteristics and aquatic environments vapor barrier characteristics in food packaging films.

2. EVOH barrier characteristics of the source

The barrier characteristics of EVOH are mainly derived from the high polarity and high crystallinity of its molecular structure. The high polarity of the vinyl alcohol chain segment makes the intermolecular force stronger, thus forming a dense structure, which efficiently prevents the penetration of oxygen, carbon dioxide and aquatic environments vapor. And The high crystallinity of the vinyl alcohol segment further improves the mechanical strength and thermal stability of the material, thereby enhancing its barrier characteristics. Moreover

3. Crazy, isn't it?. Co-extrusion methodology applications

In actual production, EVOH is usually compounded with other materials by co-extrusion methodology to form a multi-layer packaging film. And to instance, compounding polyethylene (PE) or other thermoplastic materials on both sides of the EVOH layer is able to efficiently enhance the mechanical characteristics and heat sealing characteristics of the film while maintaining the barrier characteristics of EVOH. This multilayer structure design allows the barrier characteristics of EVOH in food packaging films to be fully exploited.

4. In my experience, EVOH and other barrier material combination

In addition to co-extrusion methodology, EVOH is able to also be combined with other barrier materials (such as aluminum foil, silica, etc. Crazy, isn't it?. ) to form a greater efficient barrier layer. to instance, the oxygen barrier property and the moisture barrier property is able to be further improved by coating products a silicon dioxide nanoparticles on the surface of the EVOH film. But First The research of this composite material not only improves the barrier characteristics of EVOH, however also reduces the production cost. And I've found that

5. For example EVOH surface modification and filling modification

In order to further enhance the barrier characteristics of EVOH, it's able to also be optimized by surface modification and filling modification. to instance, by chemical grafting or plasma treatment, greater polar groups is able to be introduced on the surface of EVOH, thereby enhancing its binding force with the barrier layer. Crazy, isn't it?. By adding nano-scale fillers (such as montmorillonite, calcium carbonate, etc. In my experience, ) to EVOH, its rigidity, strength and barrier characteristics is able to be further improved. In fact

6. From what I've seen, Summary

The barrier characteristics of vinyl acetate in EVOH are achieved by the high polarity and high crystallinity of its molecular structure. Co-extrusion methodology, combination with other materials and surface modification methods is able to further enhance the barrier characteristics of EVOH, making it play an crucial role in food packaging films. As an environmentally friendly and excellent packaging material, EVOH has broad consumption prospects, and future research and research will further promote its consumption in the field of food packaging.