**4. Conclusions**

**Sample Degradation stage T0**

**Table 2.** Thermal degradation data of the samples at 10°C/min in nitrogen atmosphere.

**Figure 16.** SEM pictures for a) PP-Bagasse and b) PP-Bag + NaOH+Silane biocomposites.

To: onset of inflection of each stage in TG curves.

146 Characterizations of Some Composite Materials

ing its thermal properties.

**3.3. Morphology**

Tmax: peak of the maximum degradation rate in DTG curves.

PP 1 371 449 PP-Bag 1 264 353

PP-Bag + NaOH 1 310 355

PP-Bag + NaOH + Silane 1 311 355

to neat PP. This increment in the thermal stability of the biocomposites has been previously observed in different studies [36, 37], indicating that the incorporation of fibers in the material induces spherulite nucleation points, increasing the crystallinity of the polymer and improv-

**Figure 16** shows SEM images of fractured surfaces from PP-Bag and PP-Bag+NaOH+Silane biocomposites. Gaps between the bagasse fibers and the surrounding PP matrix can be clearly observed in **Figure 16a**, which indicates a poor interfacial adhesion between the PP matrix and the bagasse fibers [38]. For **Figure 16b**, with the chemical treatments, we can see that the gaps between bagasse and PP were reduced significantly and exhibited improved interface for the composite. This result confirms that chemical treatments expose the bagasse fibers and provided links between the cellulosic fibers and the surrounding polymer long chains, which improved the interfacial property of the hydrophobic PP matrix and the hydrophilic bagasse.

 **(°C) Tmax (°C)**

2 423 455

2 422 453

2 424 458

The chemical composition and thermal behavior of neat and chemically modified sugar bagasse fibers were studied. The biocomposites of bagasse fiber incorporated into a PP matrix were prepared by a melt-extrusion, injection, and thermocompression processes. The effects of bagasse fibers and chemical modification on the properties of the biocomposites were explored. Flexural characterization showed that bagasse fiber incorporation induces a significant improvement of flexural properties of PP. Also, the impact tests showed that the addition of silanized bagasse increases the capacity of PP to absorb energy. The DMA experiments show that bagasse fiber addition improves the maximum service temperature of the PP matrix. It was also observed that silanization process didn't improve the viscoelastic properties compared to the alkalinization treatment. However, the alkalization treatment generates an improvement against the damping of the PP matrix. Thermal studies show that bagasse fiber addition did not disturb the melting process and improves the thermal stability of the PP matrix. This study offers an environmentally friendly alternative for utilizing waste bagasse fiber generated by the sugar industry for the production of biocomposites.
