*2.2.8. Dynamic mechanical thermal analysis (DMTA)*

*2.2.2. Particle size distribution of fillers*

4 Composites from Renewable and Sustainable Materials

*2.2.3. Preparation of the composites*

granulated.

of 800 bar.

*2.2.4. Mechanical testing*

*2.2.5. Hardness tests*

*2.2.6. SEM analysis*

*2.2.7. Thermomechanical analysis (TMA)*

ment.

to determine the weight of the fillers in each mesh size range.

To evaluate the particle size distribution, fillers were classified after grinding (for rice husk) by screening into four mesh size ranges 20–35, 35–45, 45–80, and >80 per inch (approximately 500–850, 350–500, 180–350 μm, and <180 μm). The filler particles were then weighed in order

Composites were produced in a two-stage process. In the first stage, bio-fillers and polyolefine were compounded with and without compatibilizer using the twin-screw extruder Rheomex CEW100 QC, Haake, Germany. The mixing zone temperature of the extruder was 160°C for PE and 190°C for PP matrix composites. The rotation speed of the screws was 50 rpm. In the second stage, the extrudate in the form of strands was cooled to room temperature and then

The compound granules were dried at 80°C for 24 h before injection molding. The specimens were prepared using the injection molding machine MiniJet II, Haake, Germany, at cylinder temperatures of 180°C for PE and 190°C for PP matrix composites under an injection pressure

Tensile and bending tests were conducted with the Universal Testing Machine AG-X plus, Shimadzu, Japan, according to ISO 527-3 and ISO 178, respectively. Notched Izod impact tests were conducted with HIT 50P, Zwick/Roell, Germany, according to ISO 180 at room temper-

The hardness determination of the composites was carried out according to ISO 2039-1 on specimens of 80 mm × 10 mm × 4 mm. The specimens were loaded using the force of 132.39 N for a duration of 30 s. Each value obtained represents the average of 10 positions of measure-

Studies on the morphology of fillers and the tensile fracture surfaces of the composites were

The thermal expansion tests of the composites and pure polyolefine samples were conducted using a thermomechanical analyzer (TMA Q400 V7.4 Build 93, TA Instruments) from −10 to 100°C at a heating rate of 2°C/min in a nitrogen atmosphere. The expansion mode with a

constant compression load of 0.02 N was used on specimen of 5 mm × 5 mm × 4 mm.

ature. Each value obtained represents the average of at least five samples.

carried out using a FE-SEM (Ultra 55, Carl Zeiss SMT AG, Germany).

Dynamic mechanical thermal analysis was carried out (DMA Q800 V20.24 Build 43, TA Instruments) in N2 atmosphere. The dimensions of the test specimens were 17.5 mm × 10 mm × 4 mm. The tests were performed using a three-point bending-rectangular measuring system at 1-Hz test frequency. The heating rate was 1 K/min in the temperature range of −50 to 150°C. E′ (storage modulus), E″ (loss modulus), and Tan δ (damping peak) of the samples were determined as a function of temperature.
