*2.7. Mechanical Property Test*

According to GB/T 528-2009 standards, five dumbbell-shaped samples with a gauge length of 20 mm, a width of 4 mm, and a thickness of 2 mm were cut from the eight groups of samples prepared in Section 2.2. The tensile strength and elongation at the break of the samples were tested by a tensile testing machine (AGS-J, Shimadzu Corporation, Kyoto, Japan), and the tensile rate was 200 mm min−1. Then, the samples were pulled off and left to stand for five minutes, and the permanent tensile deformation was tested after the standing was completed. Finally, the arithmetic means of the test results of the five dumbbell-shaped specimens were taken for each mechanical property test result.
