**2.4. Characterization of the biocomposites**

### *2.4.1. Flexural properties*

Three-point bending flexural tests were performed with an INSTRON universal testing machine model 3366 according to the ASTM D 790–17. The tests were carried out on bars of rectangular cross section at 23°C and at a rate of crosshead motion in 1.3 mm/min. This rate was determined based on the dimensions of the specimen. Also, the distance between the supports was 50 mm, and the tests were conducted up to 5% strain. All the results were taken as the average value of five samples.

### *2.4.2. Impact properties*

The impact strength of PP and biocomposites were determined with an Izod Tinius Olsen impact pendulum equipped with a 4.53 N pendulum. Prior to the test, the materials were subjected to conditioning for 48 h at 50% relative humidity and a temperature of 25°C. The specimens were made following the standard ASTM D256, and the starting angle of the test was 55.80°. All the results were taken as the average value of five samples.
