scholarly journals PLA/PA Bio-Blends: Induced Morphology by Extrusion

Polymers ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 10 ◽  
Author(s):  
Violeta García-Masabet ◽  
Orlando Santana Pérez ◽  
Jonathan Cailloux ◽  
Tobias Abt ◽  
Miguel Sánchez-Soto ◽  
...  
Keyword(s):  
Mechanical Performance ◽  
Reactive Extrusion ◽  
Processing Parameters ◽  
Poly Lactic Acid ◽  
Twin Screw Extrusion ◽  
Extrusion Die ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Speed Rotation

The effect of processing conditions on the final morphology of Poly(Lactic Acid) (PLA) with bio-based Polyamide 10.10 (PA) 70/30 blends is analyzed in this paper. Two types of PLA were used: Commercial (neat PLA) and a rheologically modified PLA (PLAREx), with higher melt elasticity produced by reactive extrusion. To evaluate the ability of in situ micro-fibrillation (μf) of PA phase during blend compounding by twin-screw extrusion, two processing parameters were varied: (i) Screw speed rotation (rpm); and (ii) take-up velocity, to induce a hot stretching with different Draw Ratios (DR). The potential ability of PA-μf in both bio-blends was evaluated by the viscosity (p) and elasticity (k’) ratios determined from the rheological tests of pristine polymers. When PLAREx was used, the requirements for PA-μf was fulfilled in the shear rate range observed at the extrusion die. Scanning electron microscopy (SEM) observations revealed that, unlike neat PLA, PLAREx promoted PA-μf without hot stretching and the aspect ratio increased as DR increased. For neat PLA-based blends, PA-μf was promoted during the hot stretching stage. DMTA analysis revealed that the use of PLAREx PLAREx resulted in a better mechanical performance in the rubbery region (T > Tg PLA-phase) due to the PA-μf morphology obtained.

Effect of Compatibilizers on Composite Materials of Bio-Ethanol Byproduct-Poly(lacticacid)

2012 ◽  
Vol 204-208 ◽  
pp. 4088-4092
Author(s):  
Ming Ming Zhang ◽  
Xiao Huan Liu ◽  
Chun Peng Wang ◽  
Li Wei Jin
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Composite Materials ◽  
Extrusion Process ◽  
Poly Lactic Acid ◽  
Twin Screw Extrusion ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Process Effects ◽  
Properties Of Composites

The blend composite materials of bio-ethanol byproduct-Poly(lactic acid) (PLA) were produced by a twin-screw extrusion process. Effects of bio-ethanol byproduct (BEB) contents and different compatibilizers on properties of composite materials were investigated. The research showed that with the increase of contents of bio-ethanol byproduct, the mechanical properties decreased. The mechanical properties of composites were improved by adding the compatibilizers, especially the polypropylene grafted maleic anhydride (PP-MAH). When the PP-MAH content was 2.5%, the mechanical properties of the composite materials were superior to others.

Preparation and Characterization of Biodegradable Polylactic Acid/Gelatinized Cornstarch Foams

2011 ◽  
Vol 418-420 ◽  
pp. 86-89
Author(s):  
Peng Ping Xie ◽  
Ming Jun Niu ◽  
Kai Guo ◽  
Jin Zhou Chen ◽  
Xin Fa Li
Keyword(s):  
Lactic Acid ◽  
Poly Lactic Acid ◽  
Twin Screw Extrusion ◽  
Nucleation Agent ◽  
Blowing Agent ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Foam Properties ◽  
Optimized Conditions

Biodegradable foams derived from poly(lactic acid) (PLA) and gelatinized cornstarch (GS) were prepared by twin-screw extrusion using Azodicarbonamide(AC) as blowing agent and talc as nucleation agent. Foams with a relatively fine and uniform cell morphology and better foam properties were obtained under optimized conditions of PLA/GS ratio at 3:1, 1.5% AC content, and MAH and glycerol blend system.

scholarly journals Correlation between Processing Parameters and Degradation of Different Polylactide Grades during Twin-Screw Extrusion

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1333 ◽  
Author(s):  
Olga Mysiukiewicz ◽  
Mateusz Barczewski ◽  
Katarzyna Skórczewska ◽  
Danuta Matykiewicz
Keyword(s):  
Molecular Weight ◽  
Processing Parameters ◽  
High Mass ◽  
Flow Index ◽  
Processing Temperature ◽  
Color Analysis ◽  
Twin Screw Extrusion ◽  
Melt Mixing ◽  
Screw Extrusion ◽  
Twin Screw

This article presents the effect of twin-screw extrusion processing parameters, including temperature and rotational speed of screws, on the structure and properties of four grades of polylactide (PLA). To evaluate the critical processing parameters for PLA and the possibilities for oxidative and thermomechanical degradation, Fourier-transform infrared spectroscopy (FT-IR), oscillatory rheological analysis, and differential scanning calorimetry (DSC) measurements were used. The influence of degradation induced by processing temperature and high shearing conditions on the quality of the biodegradable polyesters with different melt flow indexes (MFIs)was investigated by color analysis within the CIELab scale. The presented results indicate that considering the high-temperature processing of PLA, the high mass flow index and low viscosity of the polymer reduce its time of residence in the plastifying unit and therefore limit discoloration and reduction of molecular weight due to the degradation process during melt mixing, whereas the initial molecular weight of the polymer is not an essential factor.

Crystallization Behaviour of TiO2 Nanoparticle Reinforced Polypropylene

2010 ◽  
Vol 636-637 ◽  
pp. 688-696 ◽  
Author(s):  
Andreas Noll ◽  
Nicole Knoer
Keyword(s):  
Crystallization Behaviour ◽  
Structure Development ◽  
Twin Screw Extrusion ◽  
Scanning Calorimetry ◽  
Lamellar Structures ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Wet Chemical ◽  
Wet Chemical Etching

Composites of isotactic polypropylene (iPP) with different TiO2 nanoparticle loads (0.5 vol.%, 2 vol.% and 4 vol.%) were compounded by optimized twin screw extrusion. The crystallization behaviour of these semicrystalline nanocomposites was examined by differential scanning calorimetry (DSC), scanning electron microscope (SEM) and polarized optical light microscope (POM) combined with a hot stage module to pursue in-situ the structure development. Wet chemical etching was applied to highlight morphological details like spherulites and lamellar structures for SEM observations. An obvious influence of TiO2-nanoparticles on the crystallization could be verified.

scholarly journals Plasticized Biodegradable Poly(lactic acid) Based Composites Containing Cellulose in Micro- and Nanosize

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Katalin Halász ◽  
Levente Csóka
Keyword(s):  
Lactic Acid ◽  
Microcrystalline Cellulose ◽  
Composite Films ◽  
Poly Lactic Acid ◽  
Twin Screw Extrusion ◽  
Scanning Calorimetry ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Biodegradable Poly ◽  
Poly Ethylene

The aim of this work was to study the characteristics of thermal processed poly(lactic acid) composites. Poly(ethylene glycol) (PEG400), microcrystalline cellulose (MCC), and ultrasound-treated microcrystalline cellulose (USMCC) were used in 1, 3, and 5 weight percents to modify the attributes of PLA matrix. The composite films were produced by twin screw extrusion followed by film extrusion. The manufactured PLA-based films were characterized by tensile testing, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), wide angle X-ray diffraction (WAXD), and degradation test.

scholarly journals Effect of Lignin Plasticization on Physico-Mechanical Properties of Lignin/Poly(Lactic Acid) Composites

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2089 ◽  
Author(s):  
Chan-Woo Park ◽  
Won-Jae Youe ◽  
Seok-Ju Kim ◽  
Song-Yi Han ◽  
Ji-Soo Park ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Coupling Agent ◽  
Interfacial Adhesion ◽  
Melt Flow Index ◽  
Poly Lactic Acid ◽  
Flow Index ◽  
Twin Screw Extrusion ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Polymeric Diphenylmethane Diisocyanate

Kraft lignin (KL) or plasticized KL (PKL)/poly(lactic acid) (PLA) composites, containing different lignin contents and with and without the coupling agent, were prepared in this study using twin-screw extrusion at 180 °C. Furthermore, ε-caprolactone and polymeric diphenylmethane diisocyanate (pMDI) were used as a plasticizer of KL and a coupling agent to improve interfacial adhesion, respectively. It was found that lignin plasticization improved lignin dispersibility in the PLA matrix and increased the melt flow index due to decrease in melt viscosity. The tensile strength of KL or PKL/PLA composites was found to decrease as the content of KL and PKL increased in the absence of pMDI, and increased due to pMDI addition. The existence of KL and PKL in the composites decreased the thermal degradation rate against the temperature and increased char residue. Furthermore, the diffusion coefficient of water in the composites was also found to decrease due to KL or PKL addition.

Development of nanocellulose-reinforced PLA nanocomposite by using maleated PLA (PLA-g-MA)

2017 ◽  
Vol 31 (8) ◽  
pp. 1090-1101 ◽  
Author(s):  
Somayeh Ghasemi ◽  
Rabi Behrooz ◽  
Ismail Ghasemi ◽  
Reza Shahbazian Yassar ◽  
Fei Long
Keyword(s):  
Cellulose Nanofibers ◽  
Fracture Morphology ◽  
Poly Lactic Acid ◽  
Twin Screw Extrusion ◽  
Melt Mixing ◽  
Force Microscopy ◽  
Heat Distortion Temperature ◽  
Uniform Dispersion ◽  
Screw Extrusion ◽  
Twin Screw

The goal of this research was improving the mechanical and physical properties of poly lactic acid (PLA) using cellulose nanofiber (CNF) as reinforcing and maleated PLA (PLA-g-MA) as a compatibilizer. PLA/nanocellulose composites were prepared through melt mixing with maleated PLA (5 wt%) and two levels of cellulose nanofibers (CNFs) (3 and 5 wt%) using twin screw extrusion. Nanocomposites fracture morphology, thermal properties, crystallization behavior, and mechanical behavior were determined as a function of cellulose nanofibers and PLA grafted on maleic anhydride content using scanning electron microscopy (SEM), atomic force microscopy, heat distortion temperature (HDT), impact, and tensile testing. The SEM micrographs confirmed the uniform dispersion of CNF within PLA matrix in the presence of maleated PLA. Among nanocellulose and compatibilizer, the latter one has better role in enhancement of nanocomposites HDT. Compatibilized nanocomposites (PLA/CNF5/PLAgMA5) exhibited maximum impact strength which was 131% higher than that of neat PLA. Compared to pure PLA, 138 and 40% improvements for the tensile strength and Young’s modulus can be obtained for the resulting nanocomposite with PLA/CNF5/PLAgMA5, respectively.

Influence of twin-screw extrusion conditions on the dispersion of multi-walled carbon nanotubes in a poly(lactic acid) matrix

Polymer ◽  
2008 ◽  
Vol 49 (16) ◽  
pp. 3500-3509 ◽  
Author(s):  
Tobias Villmow ◽  
Petra Pötschke ◽  
Sven Pegel ◽  
Liane Häussler ◽  
Bernd Kretzschmar
Keyword(s):  
Carbon Nanotubes ◽  
Lactic Acid ◽  
Poly Lactic Acid ◽  
Twin Screw Extrusion ◽  
Screw Extrusion ◽  
Twin Screw ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Morphology-Crystallinity Relationship in PLA-PHBV Blends Prepared via Extrusion

2013 ◽  
Vol 554-557 ◽  
pp. 1707-1714
Author(s):  
Alain Guinault ◽  
Gaelle Dutarte ◽  
Majdi Boufarguine ◽  
Guillaume Miquelard-Garnier ◽  
Cyrille Sollogoub
Keyword(s):  
Renewable Resources ◽  
Barrier Properties ◽  
Nucleating Agent ◽  
Extrusion Process ◽  
Poly Lactic Acid ◽  
Twin Screw Extrusion ◽  
Gas Barrier ◽  
Elongation At Break ◽  
Screw Extrusion ◽  
Twin Screw

Poly(lactic acid) (PLA) is a biodegradable thermoplastic polyester derived from renewable resources which may replace conventional polymers for some applications. To overcome some of its limitations such as poor gas barrier properties and low elongation at break, one method is to blend PLA with small amounts of other bio-based polymers. In this study, two processes, eg classical twin screw extrusion and a multilayer co-extrusion process have been used to combine PLA and poly(3-hydroxybutyrate-co-3-valerate) PHBV to obtain films with different blend morphologies. The effect of the morphology on the crystallinity has been studied and has hightlightned new behavior of PHBV. The addition of a nucleating agent in the PHBV to modify its crystallinity, has also been studied.

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