Dong-woo Lee

Effect of plasma treatment on mechanical properties of jute fiber/poly (lactic acid) biodegradable composites

Surface treatment of natural fibers is one of the important methods to improve the mechanical properties of the composite material. In this paper, plasma treatment (PT) for various exposure timings (30, 60, 90, and 120 s) was performed to study the mechanical properties of jute fiber and its composites using poly (lactic acid) (PLA) as the matrix. The results were compared with alkali (AT) and plasma treated (PT) fiber composites. Bundle fiber test was carried out for untreated, AT, and PT jute fiber composites. PT fiber composites showed superior properties compared to other treatments. Micro-droplet test results showed that the interfacial shear strength (IFSS) of PT fiber composite is higher than that of AT fiber composites. Mechanical properties and hardness were increased on subjecting the fiber to plasma treatment. Tensile strength, young’s modulus and flexural strength were increased in an order of 28, 17, and 20%, respectively, for plasma polymerized jute fiber composites. Moreover, plasma polymerization leads to increase (>20%) in the flexural strength than untreated fiber composites. It is inferred that plasma treatment improves the interfacial adhesion between the jute fiber and PLA. These results were also confirmed by scanning electron microscopy observations of the fractured surfaces of the composites. Overall, plasma polymerization is an effective and eco-friendly method for the surface modification of the lingo cellulosic fiber to increase the compatibility between the matrix (hydrophobic) and fiber (hydrophilic).

Effect of concentration of ATH on mechanical properties of polypropylene/aluminium trihydrate (PP/ATH) composite

Aluminium trihydrate (ATH) is being extensively added to polypropylene (PP) to make a fire retardant composite. Blends of PP/ATH composite are more fire resistant as compared to pure PP. Percentage proportion of both the constituents in the final composite depends upon the application. Improvement in the fire retardant properties of such composites have been studied and published in literature but effects on mechanical strength have not been addressed. The effect of concentration of ATH on the strength of PP/ATH composite was presented. The tensile, flexural and fracture properties were studied and discussed. Experimental tests, ASTM analytical formulae and finite element approach were used. It has been found that increase in ATH has an inverse effect on the mechanical strength.

Tensile and fire retardant properties of nanoclay reinforced Abaca/Polypropylene composite

Natural fiber composites are frequently replacing the traditional polymers for their environment friendly properties, low cost and easily available raw material. The application of these materials in making the interior parts of automobiles and airplanes can reduce the weight of the structures. But a limitation is the risk of flammability of these materials in such applications. This study is an effort to manufacture an Abaca fiber reinforced Polypropylene (PP) composite material, filled with nano-clay as flame retardant materials, to be used in the automobile and aerospace applications. Abaca is a natural fiber with good mechanical strength. Effects of nano-clay addition on the strength and fire retardant properties have been studies.