Sodium carbonate treatment of fibres to improve mechanical and water absorption characteristics of short bamboo natural fibres reinforced polyester composite

Abstract

The effect of sodium carbonate (Na 2 CO 3 ) treatment of short bamboo fibres on mechanical properties and water absorption character of polyester composite is investigated. Treatment time and Na 2 CO 3 concentration were optimised to 6 h and 5 wt-% respectively. Microscopy of the treated fibres showed a significant change in surface texture whereas; FTIR suggested the removal of amorphous compounds from the fibres that resulted in enhanced interfacial bonding between fibres and the polyester matrix. Removal of amorphous compounds was also confirmed by TGA where material loss for untreated fibres was 15% higher than the treated fibres. Composites were prepared using 10, 20 and 30 wt-% of treated and untreated fibres. Good interfacial bonding, achieved by the fibre treatment, enhanced the strength (∼24 MPa),( decreased the impact energy (from ∼36×10 −3 KJ/m 2 to ∼33×10 −3 KJ/ m 2 ) and improved the water absorption resistance (∼2%) in case of 20 wt-% fibres composite.

Hemp fiber surface modification: Its effect on mechanical and tribological properties of hemp fiber reinforced epoxy composites

“…[58][59][60][61] 3.4 | Influence of chemical treatment on water absorption properties of HFREC Figure 4 shows the percentage of water absorbed by UT, ST, and PT HFREC from a time interval of 24-192 h. All the tested composite specimens (both UT and treated fiber composites) were reinforced with the same percentage (19%) of fiber loading, therefore similar trends in water resistance were observed for all the composites. [62] From Figure 4, it can be seen that there is a sharp increase in water absorption rate up to 120 h for both UT and treated HFREC. After 120 h, the water absorption rate reduces and remains constant for all the composite specimens due to the saturation limit of the composite specimens.…”

“…Similar experimental results were also confirmed by several researchers. [62,63] From Figure 4, it can be seen that both the ST and PT HFREC showed higher resistance to water absorption in comparison with UT HFREC and PT HFREC exhibited the highest resistance to water absorption among all composites. The elimination of hemicellulose and lignin during the chemical modification of hemp fibers seems to be accountable for the treated hemp fiber composites' reduced water absorption rate.…”

“…Several researchers have mentioned similar results in their research papers. [62,67,68] Fibrillation of fibers, increase in roughness of fiber surface, and lowering of hydrophilic nature of hemp fiber caused by both sodium carbonate and peroxide treatment of the fiber contributed to the better mechanical interlocking between hemp fiber and epoxy resin resulting in improvement of tensile properties of treated HFREC. [32] The impact strength values of ST and PT HFREC are shown in Figure 8.…”

Mechanical, water absorption and tribological properties of epoxy composites filled with waste eggshell and fish scale particles

“…Several researchers also obtained similar results. [25][26][27] The fillers (both eggshell and fish scale), according to the researchers, lower the TS of the composites due to poor adherence of the filler with the matrix caused by agglomeration of the filler particles in the polymer matrix. This may have resulted in poor stress transfer from the polymer matrix.…”

Sources, Chemical Functionalization, and Commercial Applications of Nanocellulose and Nanocellulose-Based Composites: A Review

“…It has high stiffness and strength and can protect the cell wall from the outside environment. The amount of lignin in the plant cell wall ranges from 10 to 25% by weight, while the amounts of hemicellulose and cellulose are 20–35% and 35–50%, respectively [ 1 , 10 , 11 ]. The main component of the cell wall is cellulose, composed of repeating units of cellobiose, linked together with β-1,4 linkages, as shown in Figure 1 .…”