Morphology, mechanical and thermal properties of poly(lactic acid) (PLA)/natural rubber (NR) blends compatibilized by NR-graft-PLA

2017 ◽  
Vol 32 (4) ◽  
pp. 788-800 ◽  
Author(s):  
Phijittra Sookprasert ◽  
Napida Hinchiranan
Keyword(s):  
Lactic Acid ◽  
Thermal Properties ◽  
Natural Rubber ◽  
Poly Lactic Acid ◽  
Mechanical And Thermal Properties ◽  
Image Position

Abstract

Comparison between Mechanical and Thermal Properties of Polylactic Acid and Natural Rubber Blend Using Calcium Carbonate and Vetiver Grass Fiber as Fillers

2011 ◽  
Vol 410 ◽  
pp. 59-62 ◽  
Author(s):  
Punmanee Juntuek ◽  
Chaiwat Ruksakulpiwat ◽  
Pranee Chumsamrong ◽  
Yupaporn Ruksakulpiwat
Keyword(s):  
Tensile Strength ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Calcium Carbonate ◽  
Impact Strength ◽  
Natural Rubber ◽  
Poly Lactic Acid ◽  
Mechanical And Thermal Properties ◽  
Vetiver Grass ◽  
Elongation At Break

From our previous study, natural rubber (NR) was used to improve toughness of poly (lactic acid) (PLA). Impact strength and elongation at break of PLA was increased when adding NR. Moreover, by using NR-g-GMA as compatibilizer for PLA and NR blend, impact strength and elongation at break was improved. However, tensile strength and modulus of PLA/NR blend with and without NR-g-GMA were decreased. In this study, calcium carbonate (CaCO3) and vetiver grass fiber were used as fillers in PLA/NR blend. With the addition of CaCO3 into PLA/NR blend with NR-g-GMA, impact strength and modulus of the composite were further increased with a loss in tensile strength. In contrast, the addition of vetiver grass fiber into PLA/NR blend with NR-g-GMA led to an increase in tensile strength and modulus and a decrease in impact strength and elongation at break. The onset degradation temperatures of PLA composites were lower than that of PLA and PLA/NR blend.

Mechanical and Thermal Properties of Rubber Toughened Poly(Lactic Acid)

2015 ◽  
Vol 1125 ◽  
pp. 222-226 ◽  
Author(s):  
Mohd Shaiful Zaidi Mat Desa ◽  
Azman Hassan ◽  
Agus Arsad ◽  
Nor Nisa Balqis Mohammad
Keyword(s):  
Tensile Strength ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Impact Strength ◽  
Natural Rubber ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Poly Lactic Acid ◽  
Mechanical And Thermal Properties ◽  
Rubber Blends

The effect of rubber toughening on mechanical and thermal properties of poly (lactic acid) (PLA) was investigated by using three types of rubbers; natural rubber (NR), epoxidized natural rubber (ENR) and core-shell rubber (CSR). The PLA/rubber blends were prepared by melt blending in a counter-rotating twin-screw extruder, where the rubber content for all blends was kept at 5 wt%. It was found that the addition of the rubbers increased the impact strength for all blends as compared to pure PLA. On the other hand, all PLA/rubber blends showed notable decrease of Young’s modulus especially for PLA/NR blend which decreased by 72% than pure PLA. Similarly, significant decrease of tensile strength was also observed for all PLA/rubber blends. PLA/ENR blend showed a morebalance mechanical properties with fairly significant improvement of impact strength and moderate decrease of tensile strength, Young’s modulus and elongation at break. In general, PLA/NR blend showed the highest overall impact strength, while the PLA/CSR showed the highest tensile strength and Young’s modulus among the blends. Thermal analysis revealed that the Tg of PLA decreased with incorporation of the three types of rubbers with NR showing the largest decrease. This study indicates that NR, ENR and CSR are effective in enhancing toughness of PLA

Influence of extrusion screw speed on the properties of halloysite nanotube impregnated polylactic acid nanocomposites

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Chaitra Venkatesh ◽  
Yuanyuan Chen ◽  
Zhi Cao ◽  
Shane Brennan ◽  
Ian Major ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Composite Films ◽  
Polymer Melt ◽  
Poly Lactic Acid ◽  
Mechanical And Thermal Properties ◽  
Screw Speed ◽  
Halloysite Nanotube ◽  
The Past

Abstract Poly (lactic acid)/halloysite nanotube (PLA/HNT) nanocomposites have been studied extensively over the past few years owing to the interesting properties of the polymer, PLA, and the nanoclay, HNT, individually and as composites. In this paper, the influence of the screw speed during extrusion was investigated and was found to have a significant impact on the mechanical and thermal performance of the extruded PLA/HNT nanocomposites. To determine the effect of screw speed on PLA/HNT nanocomposites, 5 and 10 wt% of HNTs were blended into the PLA matrix through compounding at screw speeds of 40, 80, and 140 rpm. Virgin PLA was compounded for comparison. The resultant polymer melt was quench cooled onto a calendar system to produce composite films which were assessed for mechanical, thermal, chemical, and surface properties. Results illustrate that in comparison to 40 and 80 rpm, the virgin PLA when compounded at 140 rpm, indicated a significant increase in the mechanical properties. The PLA/HNT 5 wt% nanocomposite compounded at 140 rpm showed significant improvement in the dispersion of HNTs in the PLA matrix which in turn enhanced the mechanical and thermal properties. This can be attributed to the increased melt shear at higher screw speeds.

Preparation and Characterization of Micro-Graphite Filled Poly(Lactic Acid) Composites: Part 1 - Rheological and Thermal Properties

2020 ◽  
Vol 981 ◽  
pp. 138-143
Author(s):  
Esa N. Shohih ◽  
Mujtahid Kaavessina ◽  
Henry A. S. Lomi ◽  
Betha P. Pratiwi ◽  
Sperisa Distantina ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Conductive Polymer ◽  
Complex Viscosity ◽  
Poly Lactic Acid ◽  
Homogeneous Distribution ◽  
Mechanical And Thermal Properties ◽  
Blending Method ◽  
Stirring Time

Conductive polymer composites (CPCs) have attracted great attention of researchers due to their enhanced properties such as an adjustable electrical conductivity, good processability, good mechanical and thermal properties, etc. CPCs had many potencies for wider application in electronic devices. Poly (lactic acid) or PLA is one of the interesting polymers used in the developing of these new important materials. PLA properties are comparable to the synthetic petroleum-based polymers such as polyethylene terephthalate (PET), polypropylene (PP), etc. This research focuses on studying the rheological and thermal properties of PLA/micro-graphite as a conductive polymer composite which adjustable its electrical conductivity. In this study, the PLA/micro-graphite was prepared through solvent blending method using chloroform. The micro-graphite composition was varied from 0%, 5%, and 10 % (w/w) with different stirring time (30 and 60 minutes) and then, poured in glass mould. In the melt rheology study, the frequency sweep test showed that the complex viscosity (|η*|) of the bio-composite increased with the micro-graphite loading. The same tendency was also found in thermal property and stability. The melting temperature and thermal degradation were slightly increasing. The crystallinity of PLA was influenced by the presence of micro-graphite. In this solvent blending method, the homogeneous distribution of micro-graphite in the bio-composite required at least 60 minutes (stirred at 650 rpm and 60 °C).

scholarly journals Effect of Selected Commercial Plasticizers on Mechanical, Thermal, and Morphological Properties of Poly(3-hydroxybutyrate)/Poly(lactic acid)/Plasticizer Biodegradable Blends for Three-Dimensional (3D) Print

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1893 ◽  
Author(s):  
Přemysl Menčík ◽  
Radek Přikryl ◽  
Ivana Stehnová ◽  
Veronika Melčová ◽  
Soňa Kontárová ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Three Dimensional ◽  
Poly Lactic Acid ◽  
Mechanical And Thermal Properties ◽  
Modulated Differential Scanning Calorimetry ◽  
3D Print ◽  
3D Printed ◽  
Biodegradable Blends

This paper explores the influence of selected commercial plasticizers structure, which are based on esters of citric acid, on mechanical and thermal properties of Poly(3-hydroxybutyrate)/Poly(lactic acid)/Plasticizer biodegradable blends. These plasticizers were first tested with respect to their miscibility with Poly(3-hydroxybutyrate)/Poly(lactic acid) (PHB/PLA) blends using a kneading machine. PHB/PLA/plasticizer blends in the weight ratio (wt %) of 60/25/15 were then prepared by single screw and corotating meshing twin screw extruders in the form of filament for further three-dimensional (3D) printing. Mechanical, thermal properties, and shape stability (warping effect) of 3D printed products can be improved just by the addition of appropriate plasticizer to polymeric blend. The goal was to create new types of eco-friendly PHB/PLA/plasticizers blends and to highly improve the poor mechanical properties of neat PHB/PLA blends (with majority of PHB) by adding appropriate plasticizer. Mechanical properties of plasticized blends were then determined by the tensile test of 3D printed test samples (dogbones), as well as filaments. Measured elongation at break rapidly enhanced from 21% for neat non-plasticized PHB/PLA blends (reference) to 328% for best plasticized blends in the form of filament, and from 5% (reference) to 187% for plasticized blends in the form of printed dogbones. The plasticizing effect on blends was confirmed by Modulated Differential Scanning Calorimetry. The study of morphology was performed by the Scanning Electron Microscopy. Significant problem of plasticized blends used to be also plasticizer migration, therefore the diffusion of plasticizers from the blends after 15 days of exposition to 110 °C in the drying oven was investigated as their measured weight loss. Almost all of the used plasticizers showed meaningful positive softening effects, but the diffusion of plasticizers at 110 °C exposition was quite extensive. The determination of the degree of disintegration of selected plasticized blend when exposed to a laboratory-scale composting environment was executed to roughly check the “biodegradability”.

Sign in / Sign up

Export Citation Format

Share Document