Antistatic and Thermal Properties of Poly(Lactic Acid)/Polypropylene/Carbon Nanotube Nanocomposites

The aim of this study is to investigate the influence of carbon nanotubes (CNT) on the antistatic and thermal properties of poly(lactic acid)/polypropylene/carbon nanotubes (PLA/PP/CNT) nanocomposites. PLA/PP (blend ratio = 60:40) containing CNT (loading 1.0 to 2.5 phr) was melt-compounded followed by compression moulding. The antistatic properties of PLA/PP/CNT nanocomposites achieved at 2.5 phr CNT loading. Thermogravimetric analysis (TGA) results indicated that the thermal stability of PLA/PP/ CNT nanocomposite was higher than PLA/PP blend. Differential Scanning Calorimetry (DSC) results demonstrated that CNT reduced the cold crystallisation temperature of PLA, while increased the crystallisation temperature of PP, which evidenced the nucleatingability of CNT in the PLA/PP blends.

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Thermal and Structural Analysis of Epoxidized Jatropha Oil and Alkaline Treated Kenaf Fiber Reinforced Poly(Lactic Acid) Biocomposites

Polymers ◽

10.3390/polym12112604 ◽

2020 ◽

Vol 12 (11) ◽

pp. 2604

Author(s):

Siti Hasnah Kamarudin ◽

Luqman Chuah Abdullah ◽

Min Min Aung ◽

Chantara Thevy Ratnam

Keyword(s):

Lactic Acid ◽

Thermal Properties ◽

Alkaline Treatment ◽

Poly Lactic Acid ◽

Jatropha Oil ◽

Scanning Calorimetry ◽

Kenaf Fiber ◽

Chain Mobility ◽

Naoh Solution ◽

Thermal Stability Of

New environmentally friendly plasticized poly(lactic acid) (PLA) kenaf biocomposites were obtained through a melt blending process from a combination of epoxidized jatropha oil, a type of nonedible vegetable oil material, and renewable plasticizer. The main objective of this study is to investigate the effect of the incorporation of epoxidized jatropha oil (EJO) as a plasticizer and alkaline treatment of kenaf fiber on the thermal properties of PLA/Kenaf/EJO biocomposites. Kenaf fiber was treated with 6% sodium hydroxide (NaOH) solution for 4 h. The thermal properties of the biocomposites were analyzed using a differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). It must be highlighted that the addition of EJO resulted in a decrease of glass transition temperature which aided PLA chain mobility in the blend as predicted. TGA demonstrated that the presence of treated kenaf fiber together with EJO in the blends reduced the rate of decomposition of PLA and enhanced the thermal stability of the blend. The treatment showed a rougher surface fiber in scanning electron microscopy (SEM) micrographs and had a greater mechanical locking with matrix, and this was further supported with Fourier-transform infrared spectroscopy (FTIR) analysis. Overall, the increasing content of EJO as a plasticizer has improved the thermal properties of PLA/Kenaf/EJO biocomposites.

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Morphology, Mechanical and Thermal Properties of Poly(Lactic Acid)/Propylene-Ethylene Copolymer/Cellulose Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.972.172 ◽

2019 ◽

Vol 972 ◽

pp. 172-177

Author(s):

Sirirat Wacharawichanant ◽

Patteera Opasakornwong ◽

Ratchadakorn Poohoi ◽

Manop Phankokkruad

Keyword(s):

Thermal Stability ◽

Lactic Acid ◽

Thermal Properties ◽

Tensile Stress ◽

Cellulose Fibers ◽

Phase Morphology ◽

Poly Lactic Acid ◽

Mechanical And Thermal Properties ◽

Ethylene Copolymer ◽

Thermal Stability Of

This work studied the effects of various types of cellulose fibers on the morphology, mechanical and thermal properties of poly(lactic acid) (PLA)/propylene-ethylene copolymer (PEC) (90/10 w/w) blends. The PLA/PEC blends before and after adding cellulose fibers were prepared by melt blending method in the internal mixer and molded by compression method. The morphological analysis observed that the presence of cellulose in PLA did not change the phase morphology of PLA, and PLA/cellulose composite surfaces were observed the cellulose fibers inserted in PLA matrix and fiber pull-out. The phase morphology of PLA/PEC blends was changed from brittle fracture to ductile fracture behavior and showed the phase separation between PLA and PEC phases. The presence of celluloses did not improve the compatibility between PLA and PEC phases. The tensile stress and strain curves found that the tensile stress of PLA was the highest value. The addition of all celluloses increased Young’s modulus of PLA. The PEC presence increased the tensile strain of PLA over two times when compared with neat PLA and PLA was toughened by PEC. The incorporation of cellulose fibers in PLA/PEC blends could improve Young’s modulus, tensile strength, and stress at break of the blends. The thermal stability showed that the degradation temperatures of all types of cellulose were less than the degradation temperatures of PLA. Thus, the incorporation of cellulose in PLA could not enhance the thermal stability of PLA composites and PLA/PEC composites. The degradation temperature of PEC was the highest value, but it could not improve the thermal stability of PLA. The incorporation of cellulose fibers had no effect on the melting temperature of the PLA blend and composites.

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Improved Weathering Performance of Poly(Lactic Acid) through Carbon Nanotubes Addition: Thermal, Microstructural, and Nanomechanical Analyses

Biomimetics ◽

10.3390/biomimetics5040061 ◽

2020 ◽

Vol 5 (4) ◽

pp. 61

Author(s):

Thevu Vu ◽

Peyman Nikaeen ◽

William Chirdon ◽

Ahmed Khattab ◽

Dilip Depan

Keyword(s):

Carbon Nanotubes ◽

Lactic Acid ◽

Uv Light ◽

Degradation Mechanism ◽

Decomposition Temperature ◽

Poly Lactic Acid ◽

Accelerated Weathering ◽

Degradation Behavior ◽

Scanning Calorimetry ◽

Norrish Type

To understand the interrelationship between the microstructure and degradation behavior of poly(lactic acid) (PLA), single-walled carbon nanotubes (CNTs) were introduced into PLA as nucleating agents. The degradation behavior of PLA-CNT nanocomposites was examined under accelerated weathering conditions with exposure to UV light, heat, and moisture. The degradation mechanism proceeded via the Norrish type II mechanism of carbonyl polyester. Differential scanning calorimetry (DSC) studies showed an increase in glass transition temperature, melting temperature, and crystallinity as a result of the degradation. However, pure PLA showed higher degradation as evidenced by increased crystallinity, lower onset decomposition temperature, embrittlement, and a higher number of micro-voids which became broader and deeper during degradation. In the PLA-CNT nanocomposites, CNTs created a tortuous pathway which inhibits the penetration of water molecules deeper into the polymer matrix, making PLA thermally stable by increasing the initial temperature of mass loss. CNTs appear to retard PLA degradation by impeding mass transfer. Our study will facilitate designing environmentally friendly packaging materials that display greater resistance to degradation in the presence of moisture and UV light.

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RETRACTED: Fabrication of Poly(Lactic Acid) Nanofibers by Cotton Candy Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.728.193 ◽

2017 ◽

Vol 728 ◽

pp. 193-198

Author(s):

Rutchaneekorn Wongpajan ◽

Supaphorn Thumsorn ◽

Hiroyuki Inoya ◽

Masayuki Okoshi ◽

Hiroyuki Hamada

Keyword(s):

Differential Scanning Calorimetry ◽

Lactic Acid ◽

Thermal Properties ◽

Electron Microscope ◽

Air Pressure ◽

Poly Lactic Acid ◽

Scanning Calorimetry ◽

Cotton Candy ◽

Nozzle Temperature ◽

Scanning Electron

The poly (lactic acid) (PLA) fiber of biodegradable polymer was fabricated by cotton candy method with small nozzle. The air pressure was varied from 0.2-0.5 MPa with nozzle temperature of 210-260°C. The morphology of fiber was determined by scanning electron microscope (SEM). Thermal properties were examined using differential scanning calorimetry (DSC). SEM results suggested that diameters the PLA fiber at temperature 250°C and air pressure of 0.2 MPa were smaller than the fiber at low and high temperature. The sizes of the fibers were lower than 1 μm and the fibers were irregular size. Crystallinity significantly decreased when increasing barrel temperatures while it slightly changed when varied air pressure. The productivity of PLA fibers was around 30-180 g/h depended on controlled the nozzle temperature and the air pressure.

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Poly(lactic acid)/polypropylene and compatibilized poly(lactic acid)/polypropylene blends prepared by a vane extruder: analysis of the mechanical properties, morphology and thermal behavior

Journal of Polymer Engineering ◽

10.1515/polyeng-2014-0312 ◽

2015 ◽

Vol 35 (8) ◽

pp. 753-764 ◽

Cited By ~ 3

Author(s):

Rong-yuan Chen ◽

Wei Zou ◽

Hai-chen Zhang ◽

Gui-zhen Zhang ◽

Zhi-tao Yang ◽

...

Keyword(s):

Mechanical Properties ◽

Lactic Acid ◽

Thermal Resistance ◽

Flexural Modulus ◽

Weight Fraction ◽

Poly Lactic Acid ◽

Scanning Calorimetry ◽

Crystallization Property ◽

The Matrix ◽

Pp Blends

Abstract Poly(lactic acid) (PLA)/polypropylene (PP) blends with different weight fractions were prepared by a novel vane extruder. The mechanical properties, morphology, crystallization behavior and thermal stability of the blends were investigated. The tensile strength, flexural strength and elongation at break decreased nonlinearly when the PP content was not more than 50 wt% and then increased with an increase in the PP content. The flexural modulus decreased with increasing PP weight fraction. The PLA/PP 90:10 blend exhibited the optimum impact strength. Scanning electron microscopy measurements revealed that the PLA/PP blends were immiscible. Phase separation occurred significantly at a blend ratio of 50:50. Regarding the PLA/PP 90:10 blend, the mean diameter of the disperse-phase PP particles was the smallest at 1.11 μm. Differential scanning calorimetry measurements showed that low content of PP enhanced the crystallization of PLA. The PLA component in the blends impeded the crystallization of PP when PP was used as the matrix. The thermogravimetric analysis measurement involved a two-step decomposition process of the blends. The thermal resistance of the blends was improved by compounding with PP. As compatibilizers, both the maleic anhydride-grafted PP and the ethylene/n-butyl acrylate/glycidyl methacrylate terpolymer helped improve the mechanical properties, crystallization property and thermal resistance of the PLA/PP blends.

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Influence of Cellulose Fiber Content on Morphology and Properties of Poly(Lactic Acid)/Propylene-Ethylene Copolymer/Cellulose Composites

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.315.128 ◽

2021 ◽

Vol 315 ◽

pp. 128-133

Author(s):

Sirirat Wacharawichanant ◽

Patteera Opasakornwong ◽

Ratchadakorn Poohoi ◽

Manop Phankokkruad

Keyword(s):

Lactic Acid ◽

Thermal Properties ◽

Cellulose Fiber ◽

Poly Lactic Acid ◽

Mechanical And Thermal Properties ◽

Two Phase ◽

Degradation Temperature ◽

Cellulose Composites ◽

Ethylene Copolymer ◽

Thermal Stability Of

This work studied the effects of medium-length fibrous cellulose (MFC) on the morphology, mechanical and thermal properties of poly(lactic acid) (PLA)/propylene-ethylene copolymer (PEC) (90/10) blends. The morphological analysis of PLA/MFC composites observed MFC fibers inserted in the PLA matrix and MFC appeared agglomeration when added high MFC loading. The phase morphology showed the two-phase separation of PLA/PEC blends. The presence of PEC reduced the agglomeration of MFC fibers in polymer matrix. The tensile stress and strain curves found that the ultimate stress of PLA was the highest value and the addition of MFC increased Young’s modulus of PLA/MFC and PLA/PEC/MFC composites. The PEC presence improved the strain at breaking point of PLA/PEC blends. The thermal properties found that the incorporation of MFC did not improve the thermal stability of PLA/MFC and PLA/PEC/MFC composites due to the PLA had degradation temperature higher than MFC.

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Influence of plasticizers on thermal properties and crystallization behaviour of poly(lactic acid) films obtained by compression moulding

Polymer International ◽

10.1002/pi.5142 ◽

2016 ◽

Vol 65 (8) ◽

pp. 970-978 ◽

Cited By ~ 22

Author(s):

Justine Muller ◽

Alberto Jiménez ◽

Chelo González-Martínez ◽

Amparo Chiralt

Keyword(s):

Lactic Acid ◽

Thermal Properties ◽

Crystallization Behaviour ◽

Poly Lactic Acid ◽

Compression Moulding

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Mechanical, Physical and Thermal Properties of Sugar Palm Nanocellulose Reinforced Thermoplastic Starch (TPS)/Poly (Lactic Acid) (PLA) Blend Bionanocomposites

Polymers ◽

10.3390/polym12102216 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2216

Author(s):

A. Nazrin ◽

S. M. Sapuan ◽

M. Y. M. Zuhri

Keyword(s):

Lactic Acid ◽

Barrier Properties ◽

Thermoplastic Starch ◽

Poly Lactic Acid ◽

Thickness Swelling ◽

Compression Moulding ◽

Sem Images ◽

Increasing Trend ◽

Loading Effects ◽

Thermal Stability Of

In this paper, sugar palm nanocellulose fibre-reinforced thermoplastic starch (TPS)/poly (lactic acid) (PLA) blend bionanocomposites were prepared using melt blending and compression moulding with different TPS concentrations (20%, 30%, 40%, 60%, and 80%) and constant sugar palm nanocellulose fibres (0.5%). The physical, mechanical, thermal, and water barrier properties were investigated. The SEM images indicated different TPS loading effects with the morphology of the blend bionanocomposites due to their immiscibility. A high content of TPS led to agglomeration, while a lower content resulted in the presence of cracks and voids. The 20% TPS loading reduced the tensile strength from 49.08 to 19.45 MPa and flexural strength from 79.60 to 35.38 MPa. The thermal stability of the blend bionanocomposites was reduced as the TPS loading increased. The thickness swelling, which corresponded to the water absorption, demonstrated an increasing trend with the increased addition of TPS loading.

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Study on Aging and Recover of Poly (Lactic) Acid Composite Films with Graphene and Carbon Nanotubes Produced by Solution Blending and Extrusion

Coatings ◽

10.3390/coatings9060359 ◽

2019 ◽

Vol 9 (6) ◽

pp. 359 ◽

Cited By ~ 3

Author(s):

Rumiana Kotsilkova ◽

Polya Angelova ◽

Todor Batakliev ◽

Verislav Angelov ◽

Rosa Di Maio ◽

...

Keyword(s):

Carbon Nanotubes ◽

Lactic Acid ◽

Young’S Modulus ◽

Young's Modulus ◽

Composite Films ◽

Processing Condition ◽

Nanocomposite Films ◽

Poly Lactic Acid ◽

Scanning Calorimetry ◽

Slow Cooling

The aging, annealing, and reprocessing of the biodegradable poly (lactic) acid (PLA) based composite films incorporating graphene and carbon nanotubes were investigated in this work. Various monofiller and bifiller nanocomposite films with 6 wt.% filler content were produced by a solution-phase technique followed by extrusion. The freshly produced films were compared with the aged films after 18 months of shelf life in a room environment. The effects of aging, annealing, and melt reprocessing on the crystalline structure, the thermal stability, the hardness, and Young’s modulus were analyzed by differential scanning calorimetry (DSC), TGA, and nanoindentation methods. The fresh and the aged samples were found to have semi-crystalline materials with 3%–7% crystallinity, while the crystallinity was significantly enhanced to 34%–38% by annealing at 80 °C and subsequent slow cooling. A good dispersion was observed in the bifiller films with filler ratios of 4.5:1.5 and 1.5:4.5 [graphene nanoplatelets (GNP) to carbon nanotubes (CNT)], which affected the crystallization processes. The reprocessing at 200 °C followed by fast cooling resulted in amorphous films, which significantly reduced the hardness and Young’s modulus. The nanoindentation properties were dependent on the dispersion of nanofillers at the surfaces. The efficiency of annealing and reprocessing for the recovery and the reuse of aged nanocomposite films is discussed herein. The paper underlines that properties of the nanocomposites under investigation were influenced not only by the composition, the chemical nature of the added filler, and the processing condition, but also by the aging processes, which in turn depended on the type of nanopartcles added to PLA and the compositions. The paper provides valuable information for selection of material and processing conditions.

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Structure and Thermal Properties of Cellulose Diacetate-Graft-Poly(lactic Acid) Copolymer

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.221.85 ◽

2011 ◽

Vol 221 ◽

pp. 85-89 ◽

Cited By ~ 4

Author(s):

Wen Jian Deng ◽

Xu Pin Zhuang ◽

Ke Tian Guan ◽

Bo Wen Cheng

Keyword(s):

Lactic Acid ◽

Thermal Properties ◽

Chain Structure ◽

Decomposition Temperature ◽

Poly Lactic Acid ◽

Cellulose Diacetate ◽

Scanning Calorimetry ◽

Grafted Copolymer ◽

Acid Copolymer ◽

Processing Properties

To improve the thermal behavior of cellulose diacetate, cellulose diacetate-graft-poly(lactic acid) copolymers (CDA-g-PLAs) were synthesized by ring-opening polymerization of L-lactide using stannous octoate (Sn(Oct)2) as catalyst. The molecular structure of the copolymer was characterized by FT-IR and 1H-NMR and the thermal properties were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG-DTA). The results showed that the product was grafted copolymer of cellulose diacetate-graft-poly(lactic acid) with different side-chain structure. The thermal processing properties of CDA-g-PLAs are remarkably improved with melting temperature(Tm) about 140°C which lower than that of CDA and decomposition temperature (Td) higher than 260°C.

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