Thermomechanical, Crystallization and Melting Behavior of Plasticized Poly(Lactic Acid) Nanocomposites

The incorporation of filler and plasticizer provides effective nucleation and mechanical reinforcement in polymer composites to impart flexibility, toughness, thermal stability and tensile strength of PLA composites that can be used in the development of packaging applications. In this paper, the inclusion of plasticizer and reinforcement of nanofiller in PLA matrix prepared using solvent casting method aims to improve the thermomechanical properties that consequently alter the crystallization and melting behavior of PLA composites. Plasticized PLA with different percentages of TiO2 at 2.0, 3.5, 5.0 and 7.0 % w/w were dispersed in PLA solution using mechanical mixer and ultrasonication technique to introduce a matrix reinforcing nanophase within the composite. The thermomechanical properties and thermal behavior of PLA nanocomposites were characterized using dynamic mechanical analysis (DMA) and differential scanning calorimeter (DSC). DSC cooling curves at low scanning rate of 2.0 K·min-1 proved that the presence of TBC in PLA matrix increased the crystallinity of plasticized PLA nanocomposites that initiated the formation of perfect spherulites. TBC increased the crystallization activity during cooling, which in turn reduced the recrystallization effect on heating, in parallel with DMA results that revealed small peak of cold-crystallization activity on PLA nanocomposites with the addition of plasticizer observed at temperature range of 80 °C to 100 °C. Nanofiller induced nucleation for crystallization of PLA matrix and plasticizer accelerated the overall crystallization process. Considerable adjustments of plasticizer and nanofiller in PLA matrix in having a good balance of stiffness and flexibility are a practical strategy that has a potential in biopolymer medical engineering and in the development of packaging applications.

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Thermomechanical Properties and Thermal Behavior of Poly(Lactic Acid) Composites Reinforced with TiO2 Nanofiller

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.317.341 ◽

2021 ◽

Vol 317 ◽

pp. 341-350

Author(s):

Nur Ain Syafiqah Sudin ◽

Norlinda Daud ◽

Izan Roshawaty Mustapa ◽

Mohammed Zorah

Keyword(s):

Mechanical Properties ◽

Lactic Acid ◽

Thermal Behavior ◽

Storage Modulus ◽

Medical Engineering ◽

Physical And Mechanical Properties ◽

Mechanical Analysis ◽

Thermomechanical Properties ◽

Filler Loading ◽

Poly Lactic Acid

The reinforcement effect of nanofiller in polymer enhanced the thermal stability, physical and mechanical properties of poly (lactic acid) (PLA) composites with good reinforcing capabilities for bio-based polymers. In this paper, the effect of reinforcement of titanium dioxide (TiO2) nanofiller on the mechanical properties and thermal behavior of PLA matrix are reported. PLA/TiO2 nanocomposites with different percentages of 2.0, 3.5, 5.0 and 7.0 %∙w/w were prepared by using solvent casting method and hot press machine. TiO2 were dispersed in PLA matrix using mechanical mixer and ultrasonication technique. The mechanical properties and thermal behavior of PLA nanocomposites were characterized using dynamic mechanical analysis (DMA) and differential scanning calorimeter (DSC). The increased in storage modulus by the addition of nanofiller with the highest increment provided by 2.0 %·w/w TiO2 indicated a strong influence and better interfacial bonding between nanofiller and PLA matrix. An increased in storage modulus started at 100 °C that linked to the cold crystallization (Tcc) of PLA composites is in agreement with DSC result. The Tcc shifted to higher temperature as the content of nanofiller increased and this result were observed at 2.0 %·w/w of the nanofiller content. Reinforcement of nanofiller increased the melting temperature from lower filler loading until 5.0 %·w/w. The incorporation of TiO2 nanofiller as the reinforcement agent for PLA has a potential in biopolymer medical engineering and packaging industry, a highly competitive application with a great demand of cost and performance.

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Thermal and Thermomechanical Properties of Poly(butylene succinate) Nanocomposites

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.18231 ◽

2008 ◽

Vol 8 (4) ◽

pp. 1679-1689 ◽

Cited By ~ 1

Author(s):

Mamookho E. Makhatha ◽

Suprakas Sinha Ray ◽

Joseph Hato ◽

Adriaan S. Luyt

Keyword(s):

Thermal Stability ◽

Tensile Modulus ◽

Melting Behavior ◽

Mechanical Analysis ◽

Thermomechanical Properties ◽

Scanning Calorimetry ◽

Melt Mixing ◽

Butylene Succinate ◽

Modulated Differential Scanning Calorimetry ◽

Thermal Stability Of

This article describes the thermal and thermomechanical properties of poly(butylene succinate) (PBS) and its nanocomposites. PBS nanocomposites with three different weight ratios of organically modified synthetic fluorine mica (OMSFM) have been prepared by melt-mixing in a batch mixer at 140 °C. The structure and morphology of the nanocomposites were characterized by X-ray diffraction (XRD) analyses and transmission electron microscopy (TEM) observations that reveal the homogeneous dispersion of the intercalated silicate layers into the PBS matrix. The thermal properties of pure PBS and the nanocomposite samples were studied by both conventional and temperature modulated differential scanning calorimetry (DSC) analyses, which show multiple melting behavior of the PBS matrix. The investigation of the thermomechanical properties was performed by dynamic mechanical analysis. Results reveal significant improvement in the storage modulus of neat PBS upon addition of OMSFM. The tensile modulus of neat PBS is also increased substantially with the addition of OMSFM, however, the strength at yield and elongation at break of neat PBS systematically decreases with the loading of OMSFM. The thermal stability of the nanocomposites compared to that of the pure polymer sample was examined under both pyrolytic and thermooxidative environments. It is shown that the thermal stability of PBS is increased moderately in the presence of 3 wt% of OMSFM, but there is no significant effect on further silicate loading in the oxidative environment. In the nitrogen environment, however, the thermal stability systematically decreases with increasing clay loading.

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Influence of filler hybridization on thermomechanical properties of hemp/silver epoxy composite

Polymers and Polymer Composites ◽

10.1177/0967391120978112 ◽

2020 ◽

pp. 096739112097811

Author(s):

Munjula Siva Kumar ◽

Santosh Kumar ◽

Krushna Gouda ◽

Sumit Bhowmik

Keyword(s):

Thermal Conductivity ◽

Silver Nanoparticles ◽

Epoxy Polymer ◽

Hybrid Composites ◽

Conductive Filler ◽

Weight Fraction ◽

Mechanical Analysis ◽

Thermomechanical Properties ◽

Material Behavior ◽

Good Crystallinity

The polymer composite material’s thermomechanical properties with fiber as reinforcement material have been widely studied in the last few decades. However, these fiber-based polymer composites exhibit problems such as fiber orientation, delamination, fiber defect along the length and bonding are the matter of serious concern in order to improve the thermomechanical properties and obtain isotropic material behavior. In the present investigation filler-based composite material is developed using natural hemp and high thermal conductive silver nanoparticles (SNP) and combination of dual fillers in neat epoxy polymer to investigate the synergetic influence. Among various organic natural fillers hemp filler depicts good crystallinity characteristics, so selected as a biocompatible filler along with SNP conductive filler. For enhancing their thermal conductivity and mechanical properties, hybridization of hemp filler along with silver nanoparticles are conducted. The composites samples are prepared with three different combinations such as sole SNP, sole hemp and hybrid (SNP and hemp) are prepared to understand their solo and hybrid combination. From results it is examined that, chemical treated hemp filler has to maximized its relative properties and showed, 40% weight % of silver nanoparticles composites have highest thermal conductivity 1.00 W/mK followed with hemp filler 0.55 W/mK and hybrid 0.76 W/mK composites at 7.5% of weight fraction and 47.5% of weight fraction respectively. The highest tensile strength is obtained for SNP composite 32.03 MPa and highest young’s modulus is obtained for hybrid composites. Dynamic mechanical analysis is conducted to find their respective storage modulus and glass transition temperature and that, the recorded maximum for SNP composites with 3.23 GPa and 90°C respectively. Scanning electron microscopy examinations clearly illustrated that formation of thermal conductivity chain is significant with nano and micro fillers incorporation.

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