3.3.5 Mechanical properties
The mechanical properties of the samples are shown in Figure 9. Figure 9
(a) is the tensile strength of the sample. The tensile strength of the
composites are lower than that of pure PP. Compared with PP, the tensile
strength of SCG/PP and NSCG/PP composites decreased by 56.3 % and 53.3
%, respectively, while ASCG/PP only decreased by 34.4 %. As shown in
Figure 9 (b), the elongation at break decreased by 61.9 %, 67.2 % and
43.8 %, respectively. In addition, the elastic modulus of the composite
increases, as shown in Figure 9 (c). The larger the elastic modulus, the
harder the material. SCG acts as an inactive filler, which causes force
concentration inside pp, resulting in a decrease in the tensile strength
of pp. The different dispersion degree of the three fillers in PP leads
to the difference of mechanical properties. In contrast, ASCG / PP is
stronger and tougher. This can meet the most basic anti-cracking
requirements for food packaging materials.