Mechanical, thermal and morphological properties of poly(lactic acid)/natural rubber nanocomposites

Abstract

This paper reports a melt blend of poly(lactic acid)/liquid natural rubber with Cloisite C30B (C30B). The mechanical, thermal and morphological properties of poly(lactic acid)/liquid natural rubber and nanocomposites were investigated. Results indicate that Young’s modulus and flexural modulus increased with the addition of C30B to the poly(lactic acid)/liquid natural rubber blend. The elongation at break of poly(lactic acid)/liquid natural rubber increased significantly as compared to nanocomposite with 1% of C30B, i.e. from 37.3% to 62.4%. Nevertheless, the elongation at break and impact strength decreased gradually when nanoclay content increased above 3%, suggesting the addition of clay changed the strain response in the blend systems. The incorporation of nanoclay in the poly(lactic acid)/liquid natural rubber blends lowered the glass transition temperature values relative to poly(lactic acid). This behavior may be associated with more free volume available in the nanocomposite blend systems compared with pure poly(lactic acid). Morphological analyses by scanning electron microscope and transmission electron microscope revealed that different types of morphologies exist for poly(lactic acid)/liquid natural rubber and nanocomposites. This study indicates that poly(lactic acid)/liquid natural rubber-toughened nanocomposites with a higher modulus and that thermal stability could be produced.

Tensile and Thermal Behaviours of Poly(lactic Acid)/Liquid Natural Rubber Blend Matrix Incorporated Nickel Zinc Ferrite Nanoparticles

“…Comparing to that, the highest tensile strength (40.90 MPa) and Young's modulus (7.50 GPa) were achieved at nanocomposite incorporated with 2 wt.% NiZn ferrite, which are increased by 36.65% and 41.78%, respectively. This could be ascribed to the good interfacial interaction between the PLA and NiZn ferrite as a result of the enhanced nanofiller dispersion [2]. When NiZn ferrite nanoparticles added at above 2 wt.%, the tensile strength and Young's modulus decreased gradually from 3 to 5 wt.%.…”

“…Due to the renewability issue and comparable properties with petroleum based polymers, PLA is gaining its popularity [1]. However, as well-established, high brittleness is the main weakness for PLA to be applied in most of the commercial applications [2]. As for that, toughening of PLA by blending with rubber is an applicable method, as a result of the ductility properties imparted by natural rubber (NR).…”

“…Another advantage could be, NR is derived from renewable sources. Therefore, blending of PLA and NR such as liquid natural rubber (LNR) which is a low molecular weight version of NR, could be a good choice to enhance the toughness of PLA without affecting its biodegradability [1,2]. Somehow, PLA based blending does not provide any high end performance, for examples, electrical, magnetic, conductivity properties and etc.…”

Effect of Multi Walled Carbon Nanotubes on Thermal Conductivity of Polylactic Acid Nanocomposite

“…In the double bond region, the IR band at 1747 is assigned as carbonyl group of C=O bond. The peaks at 868 and 755 are related to the amorphous and crystalline region [4]. The peak at 1080 belongs to C-O-C stretching of the PLA.…”

“…The optimal LNR content in the blend was found to be 10 wt.% where it shows it has improve the brittleness and crystallization ability of the PLA [4]. MWCNT was mixed with LNR using ultrasonication method before melt blended with PLA.…”