Fabrication of Functionalized Graphene Oxidemaleic Anhydride Grafted Polypropylene Composite Film with Excellent Gas Barrier and Anticorrosion Properties

Nylon film has the advantages of light weight and easy processing, so it has become the preferred barrier material, but its application is limited because of its poor gas barrier performance. Graphene is a kind of material with two-dimensional network structure and excellent gas barrier properties.

In this paper, modified graphene oxide (mGO-ODA) was prepared by reducing graphene oxide (GO) with octadecylamine (ODA) and compounded with polypropylene maleic anhydride graft copolymer (MAPP). A series of mGO-ODA/MAPP composites were prepared as coatings. In the later stage, the coating material was compounded onto the nylon film by spraying technology to obtain the nylon composite film with excellent gas barrier performance.

Figures 1 and 2 are SEM diagrams of cross-sectional of coating materials and composite films with different mGO-ODA contents, respectively. It can be seen from figure 1 that the cross-sectional of pure MAPP are very smooth, while the cross-sectional of all composites are rough, indicating that the compatibility of mGO-ODA and MAPP in the composites is good, and the mechanical properties are improved. Figure 2 shows that there is a good adhesion between the nylon film and the coating due to the hydrogen bond and chemical bond between the end group of nylon and the anhydride part of MAPP.

Figure 3 shows the tensile stress-strain curves (a) and elastic modulus diagrams (b) of different types of coatings, MAPP and nylon composite films. The figure shows that compared with nylon film, the tensile strength and elastic modulus of nylon composite film are greatly improved, and increase with the increase of mGO-ODA content, indicating that MAPP can improve the tensile strength and elastic modulus of nylon film.

At the same time, graphene oxide also enhances the mechanical properties of nylon composite film through good interface bonding between MAPP and nylon.Gas barrier test and electrochemical corrosion test show that the H₂ and O₂ barrier performance and anti-corrosion performance of nylon composite film have been improved.

Fig. 1.FESEM images of the fractured surfaces of (a)pure MAPP,

(b) 15%mGO-ODA/MAPP, (c) 30%mGO-ODA/MAPP,

(d) 45% mGO-ODA/MAPP, and(e) 60% mGO-ODA/MAPP.

Fig. 2. Cross-sectional FESEM images of (a) 15%mGO-ODA/MAPP,

(b) 30% mGO-ODA/MAPP, (c)45% mGO-ODA/MAPP,

and(d)60% mGO-ODA/MAPP-coated nylon films.

Fig. 3 (a) tensile stress-strain curves of different types of coatings, MAPP and nylon composite films;

 (b) elastic modulus diagram