The pencil hardness values of the modified graphite nanosheet coatings with different contents are shown in Fig. 3-11.
Figure 3-11 Pencil hardness of modified graphite nanosheet coatings with different contents
With the increase of the content of modified graphite nanosheets, the hardness of the coating increases. When the addition amount is 7.5%, the pencil hardness of the graphite nanosheet coating reaches 3H. When the content continues to increase, the pencil hardness of the coating gradually decreases. When the addition amount reaches 12.5%, the pencil hardness of the coating is 1H. Too low or too high content of modified graphite nanosheets will not improve the hardness of the paint film. Since the bonding force between graphite nanosheets is weak and relatively soft, the hardness of the coating will decrease when the content is too high. In addition, the graphite nanosheets will agglomerate more seriously, which will also become a defect of the coating, thereby reducing the hardness of the coating.
