Oxygen barrier film, food packaging material comprising same, and method for producing oxygen barrier film
Provided are an oxygen barrier film, a food wrapper including the same, and a method of preparing the oxygen barrier film. The oxygen barrier film may include: a base layer; and an organic/inorganic hybrid layer located on the base layer and including a natural hydrogel and a silane coupling agent.
1. A method of preparing an oxygen barrier film, the method comprising:
adding a silane coupling agent and a filler to an aqueous protein solution to prepare a pre-composition for an organic-inorganic hybrid layer;
heat-treating and then cooling the pre-composition for the organic-inorganic hybrid layer to prepare a composition for the organic-inorganic hybrid layer; and
applying the composition for the organic-inorganic hybrid layer onto a base layer to prepare the oxygen barrier film,
wherein
the aqueous protein solution comprises a protein selected from the group consisting of whey protein isolate (WPI), whey protein concentrate (WPC), soy protein isolate (SPI), rice protein isolate (RPI), oat Protein (oat protein isolate: OPI), pea protein isolate (PPI), casein, sodium caseinate and wheat protein (gluten),
the filler is selected from the group consisting of sorbitol, fructose, sucrose, mannitol, propylene glycol, glycerol, and polyethylene glycol,
the silane coupling agent is an aminosilane,
the silane coupling agent reacts with the aqueous protein solution during the heat-treating to form a crosslinked protein-silane network via amide bonding, and
the filler is disposed in holes of the crosslinked protein-silane network.
2. The method of claim 1 , wherein the heat treatment is performed at a temperature of 70° C. to 120° C. for 1 hour to 5 hours.
3. The method of claim 1 , wherein the filler is the sorbitol.
4. The method of claim 1 , wherein the protein comprised in the aqueous protein solution is a whey protein.