Effect of chemical treatment on the thermal properties of hybrid natural fiber‐reinforced composites

Abstract

The main objective of this work is to study the effect of chemical treatment on the thermal properties of hybrid natural fiber-reinforced composites (NFRCs). Different chemical treatments [i.e., alkalized and mixed (alkalized+ silanized)] were used to improve the adhesion between the natural fibers (jute, ramie, sisal, and curauá) and the polymer matrix. A differential scanning calorimetry, thermogravimetry, and a dynamic mechanical analysis were performed to study the thermal properties of hybrid NFRC. It was found that the chemical treatments increased the thermal stability of the composites. Scanning electron microscopy images showed that the chemical treatments altered the morphology of the natural fibers. A rougher surface was observed in case of alkali treated fiber, whereas a thin coating layer was formed on the fiber surface during the mixed treatment. However, for some fibers (i.e., sisal and rami), the chemical treatment has a positive impact on the composite properties, whereas for the jute and curauá composites, the best behavior was found for untreated fibers.

Mechanical and Thermal Characterization of Natural Intralaminar Hybrid Composites Based on Sisal

“…It is known that in a hybrid composite, failure is directly related to the strain at break of the individual reinforcing fibers [39] and it was shown in the literature that the strain at break of the glass fiber (2.5%) is lower compared to the curauá fiber (4.5%) [40], which may explain the lower strain failure of S+G composites compared to S+C. These results are in agreement with the literature [19,23,31]. Table 3 presents the data obtained from the flexural tests as a function of hybridization.…”

“…Figure 6 shows the composite thermal degradation as a function of hybridization. It is well known that when the material is degraded, it loses mass in the form of volatiles [31]. From Figure 6a it can be seen that the TG curves showed similar tendencies.…”

“…The difference in chemical composition between natural fibers can result in different mechanical and thermal properties of the hybrid composites. Table 1 presents the chemical composition and mechanical properties of the natural fibers used in this work [19,21,23,31]. The properties of the glass fiber used were as follow: density (2.55 g/cm 3 ), tensile strength (2000-3500 MPa), Young's modulus (70-76 GPa) and elongation at break (1.8%-4.8%) [17,21].…”

“…Chemical composition, physical and mechanical properties of the natural fibers studied[19,21,23,31].…”

A critical review on erosion wear characteristics of polymer matrix composites

“…The results revealed that erosion resistance of treated samples is 20%-30% lower than untreated samples for 60°impact angle. Chemical treatment of natural fibers intended to improve the adhesion with polymer matrices were reported by numerous researchers [80][81][82][83][84][85][86][87][88]. However they had used different chemicals in their studies.…”