2.6.1. Mechanical Properties

Tensile strength (TS, MPa), elongation at break (EAB, %) and elastic modulus (EM, GPa) of the films were measured with an XLW auto tensile tester (Labthink Instruments Co. Ltd., Jinan, China) according to ASTM (American Society of Testing Materials) D882-12 (2012). The samples were cut into strips (dimensions, 150 mm × 15 mm). The initial distance between the grips was 100 mm and the test speed was set at 100 mm/min. Each test was repeated at least six times.
