Dispersion of Micro Fibrillated Cellulose (MFC) in Poly(lactic acid) (PLA) from Lab-Scale to Semi-Industrial Processing Using Biobased Plasticizers as Dispersing Aids

In the present study, two commercial typologies of microfibrillated cellulose (MFC) (Exilva and Celish) with 2% wt % were firstly melt-compounded at the laboratory scale into polylactic acid (PLA) by a microcompounder. To reach an MFC proper dispersion and avoid the well-known aglomeration problems, the use of two kinds of biobased plasticisers (poly(ethylene glycol) (PEG) and lactic acid oligomer (OLA)) were investigated. The plasticizers had the dual effect of dispersing the MFC, and at the same time, they counterbalanced the excessive stiffness caused by the addition of MFC to the PLA matrix. Several preliminaries dilution tests, with different aqueous cellulose suspension/plasticizer weight ratios were carried out. These tests were accompanied by SEM observations and IR and mechanical tests on compression-molded films in order to select the best plasticizer content. The best formulation was then scaled up in a semi-industrial twin-screw extruder, feeding the solution by a peristaltic pump, to optimize the industrial-scale production of commercial MFC-based composites with a solvent-free method. From this study, it can be seen that the use of plasticisers as dispersing aids is a biobased and green solution that can be easily used in conventional extrusion techniques.

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Characterization of Different Chemical Blowing Agents and Their Applicability to Produce Poly(Lactic Acid) Foams by Extrusion

Applied Sciences ◽

10.3390/app8101960 ◽

2018 ◽

Vol 8 (10) ◽

pp. 1960 ◽

Cited By ~ 12

Author(s):

Ákos Kmetty ◽

Katalin Litauszki ◽

Dániel Réti

Keyword(s):

Lactic Acid ◽

Cell Structure ◽

Mechanical Tests ◽

Poly Lactic Acid ◽

Foaming Agent ◽

Blowing Agents ◽

Twin Screw ◽

The Individual ◽

Chemical Blowing Agents

This study presents the applicability of different types (exothermic and endothermic) of chemical blowing agents (CBAs) in the case of poly(lactic acid) (PLA). The amount of foaming agent is a fixed 2 wt%. We used a twin-screw extruder and added the individual components in the form of dry mixture through the hopper of the extruder. We characterized the PLA matrix and the chemical blowing agents with different testing methods. In case of the produced foams we carried out morphological and mechanical tests and used scanning electron microscopy to examine cell structure. We showed that PLA can be successfully foamed with the use of chemical blowing agents. The best results were achieved with an exothermic CBA and with PLA type 8052D. The cell population density of PLA foams produced this way was 4.82 × 105 cells/cm3, their expansion was 2.36, their density 0.53 g/cm3 and their void fraction was 57.61%.

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

Journal of Engineering ◽

10.1155/2013/329379 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 29

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.

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Compatibilization of Poly(Lactic Acid) (PLA) and Bio-Based Ethylene-Propylene-Diene-Rubber (EPDM) via Reactive Extrusion with Different Coagents

Polymers ◽

10.3390/polym12030605 ◽

2020 ◽

Vol 12 (3) ◽

pp. 605

Author(s):

Alexander Piontek ◽

Oscar Vernaez ◽

Stephan Kabasci

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Lactic Acid ◽

Reactive Extrusion ◽

Poly Lactic Acid ◽

Ethylene Propylene ◽

Twin Screw ◽

Ethylene Propylene Diene Rubber ◽

Poly Ethylene ◽

Diene Rubber

Much effort has been made to enhance the toughness of poly (lactic acid) (PLA) to broaden its possible range of usage in technical applications. In this work, the compatibility of PLA with a partly bio-based ethylene-propylene-diene-rubber (EPDM) through reactive extrusion was investigated. The concentration of EPDM in the PLA matrix was in the range of up to 20%. The reactive extrusion was carried out in a conventional twin-screw extruder. Contact angle measurements were performed to calculate the interfacial tension and thus the compatibility between the phases. The thermal and mechanical properties as well as the phase morphology of the blends were characterized. A copolymer of poly (ethylene-co-methyl acrylate-co-glycidyl methacrylate) (EMAGMA) was used as compatibilizer, which leads to a significant reduction in the particle size of the dispersed rubber phase when compared with the blends without this copolymer. The use of EMAGMA combined with soybean oil (SBO) and a radical initiator enhances the elongation at break of the compound. The results indicate that the reduction of the particle size of the dispersed phase obtained with the compatibilizer alone is not sufficient to improve the mechanical properties of the blend system. The induced radical reactions also influenced the mechanical properties of the blend significantly.

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Tailoring Poly(lactic acid) (PLA) Properties: Effect of the Impact Modifiers EE-g-GMA and POE-g-GMA

Polymers ◽

10.3390/polym14010136 ◽

2021 ◽

Vol 14 (1) ◽

pp. 136

Author(s):

Edson Antonio dos Santos Filho ◽

Carlos Bruno Barreto Luna ◽

Danilo Diniz Siqueira ◽

Eduardo da Silva Barbosa Ferreira ◽

Edcleide Maria Araújo

Keyword(s):

Lactic Acid ◽

Glycidyl Methacrylate ◽

Poly Lactic Acid ◽

Screw Extruder ◽

Crystallinity Degree ◽

Twin Screw ◽

Injection Molded ◽

Packaging Industry ◽

Poly Ethylene ◽

The Impact

Poly(ethylene-octene) grafted with glycidyl methacrylate (POE-g-GMA) and ethylene elastomeric grafted with glycidyl methacrylate (EE-g-GMA) were used as impact modifiers, aiming for tailoring poly(lactic acid) (PLA) properties. POE-g-GMA and EE-g-GMA was used in a proportion of 5; 7.5 and 10%, considering a good balance of properties for PLA. The PLA/POE-g-GMA and PLA/EE-g-GMA blends were processed in a twin-screw extruder and injection molded. The FTIR spectra indicated interactions between the PLA and the modifiers. The 10% addition of EE-g-GMA and POE-g-GMA promoted significant increases in impact strength, with gains of 108% and 140%, respectively. These acted as heterogeneous nucleating agents in the PLA matrix, generating a higher crystallinity degree for the blends. This impacted to keep the thermal deflection temperature (HDT) and Shore D hardness at the same level as PLA. By thermogravimetry (TG), the blends showed increased thermal stability, suggesting a stabilizing effect of the modifiers POE-g-GMA and EE-g-GMA on the PLA matrix. Scanning electron microscopy (SEM) showed dispersed POE-g-GMA and EE-g-GMA particles, as well as the presence of ligand reinforcing the systems interaction. The PLA properties can be tailored and improved by adding small concentrations of POE-g-GMA and EE-g-GMA. In light of this, new environmentally friendly and semi-biodegradable materials can be manufactured for application in the packaging industry.

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Mechanical and Optical Properies of Poly Lactic Acid Modified Linear- Low Density Polyethylene / Low Density Polyethylene (Lldpe/Ldpe) Blend Blown Film

International Journal of Mechanical and Industrial Engineering ◽

10.47893/ijmie.2012.1080 ◽

2012 ◽

pp. 122-125

Author(s):

Omveer Singh ◽

Pradeep Upadhyaya ◽

T.k Mishra ◽

Navin Chand

Keyword(s):

Lactic Acid ◽

Polylactic Acid ◽

Low Density Polyethylene ◽

Poly Lactic Acid ◽

Low Density ◽

Melt Blending ◽

Linear Low Density Polyethylene ◽

Blown Film ◽

Twin Screw ◽

Poly Ethylene

Poly lactic acid (PLA) is well known aliphatic poly-esters derived from corn and sugar beets, and degrades into nontoxic compounds in landfill. Melt blending of poly lactic acid and linear low density polyethylene (LLDPE) was performed in an effort to toughen polylactic acid. Melt blending of linear low density polyethylene (LLDPE) and polylactic Acid (PLA) and Low density poly ethylene (LDPE) were performed in a twin screw extruder with post extrusion blown film. The blend compositions were optimized by mechanical properties. On the basis of this, LLDPE 80 wt % LDPE 20 wt% and 1-4 wt% poly lactic acid (PLA) were found to be an optimum composition. The blends were characterized according to their mechanical and optical behavior. This blend may be used for packaging application.

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Preparation and characterization of solution blended poly(ethylene terephthalate-co-ethylene furandicarboxylate) and poly(lactic acid)

Future Energy, Environment and Materials ◽

10.2495/feem130771 ◽

2014 ◽

Author(s):

Hae-Ri Kim ◽

Byeong-Uk Nam ◽

Yeon-Hee Kim

Keyword(s):

Lactic Acid ◽

Ethylene Terephthalate ◽

Poly Lactic Acid ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene

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The effect of poly(ethylene glycol) as plasticizer in blends of poly(lactic acid) and poly(butylene succinate)

Journal of Applied Polymer Science ◽

10.1002/app.43044 ◽

2015 ◽

Vol 133 (8) ◽

pp. n/a-n/a ◽

Cited By ~ 18

Author(s):

Weraporn Pivsa-Art ◽

Kazunori Fujii ◽

Keiichiro Nomura ◽

Yuji Aso ◽

Hitomi Ohara ◽

...

Keyword(s):

Lactic Acid ◽

Ethylene Glycol ◽

Poly Lactic Acid ◽

Poly Ethylene Glycol ◽

Butylene Succinate ◽

Poly Ethylene

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Immobilization of trypsin onto poly(ethylene terephthalate)/poly(lactic acid) nonwoven nanofiber mats

Biochemical Engineering Journal ◽

10.1016/j.bej.2015.04.026 ◽

2015 ◽

Vol 104 ◽

pp. 48-56 ◽

Cited By ~ 15

Author(s):

Teresa R. Silva ◽

Daniela P. Rodrigues ◽

Jorge M.S. Rocha ◽

M. Helena Gil ◽

Susana C.S. Pinto ◽

...

Keyword(s):

Lactic Acid ◽

Ethylene Terephthalate ◽

Poly Lactic Acid ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene ◽

Nanofiber Mats

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Biodegradable Microfluidic Device: Hydrolysis, Decomposition and Surface Modification

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.447-448.755 ◽

2010 ◽

Vol 447-448 ◽

pp. 755-759 ◽

Cited By ~ 1

Author(s):

Jia En Low ◽

Wei Xiang Koh ◽

Joon Kit Lai ◽

Yan Jie Lee ◽

Xu Li ◽

...

Keyword(s):

Lactic Acid ◽

Microfluidic Device ◽

Ph Value ◽

Blood Compatibility ◽

Blood Clot ◽

Hydrophobic Surface ◽

Poly Lactic Acid ◽

Water Contact ◽

Chemical Grafting ◽

Poly Ethylene

Poly(lactic acid) (PLA) is a biodegradable and biocompatible aliphatic polyester whose lactic acid monomers are derived from renewable resources such as corn and sugar beet. As a thermal plastic it can be processed through compounding and injection. As such, we have developed a microfludic device using PLA aimed at blood dialysis application. To quantify the degradation of PLA, its hydrolysis at different pH value was studied. To study the bioresorbable property of these fabricated devices, its decomposition was tested by morphology observation and weight change measurements after embedding in soil under simulated environmental conditions. Upon contact with a hydrophobic surface, platelets and prothrombin are always activated to attach to the surface, resulting in blood clot. This would block the blood flow through the dialysis channels in the microfluidic device. To improve the hydrophilicity, hence the blood compatibility, chemical grafting of a hydrophilic polymer, poly(ethylene oxide) methacrylate (PEGmA), onto the surface of PLA microfluidic device was carried out and the changes in hydrophilicity was monitored through measuring the water contact angle. Our results indicate that chemical grafting of PEGmA significantly improves the hydrophilicity of the device surface.

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