scholarly journals Ductility and Toughness Improvement of Injection-Molded Compostable Pieces of Polylactide by Melt Blending with Poly(ε-caprolactone) and Thermoplastic Starch

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2138 ◽  
Author(s):  
Luis Quiles-Carrillo ◽  
Nestor Montanes ◽  
Fede Pineiro ◽  
Amparo Jorda-Vilaplana ◽  
Sergio Torres-Giner
Keyword(s):  
Mechanical Performance ◽  
Thermoplastic Starch ◽  
Thermomechanical Properties ◽  
Ternary Blend ◽  
Melt Blending ◽  
Plastic Materials ◽  
Twin Screw ◽  
Spherical Domains ◽  
Injection Molded

The present study describes the preparation and characterization of binary and ternary blends based on polylactide (PLA) with poly(ε-caprolactone) (PCL) and thermoplastic starch (TPS) to develop fully compostable plastics with improved ductility and toughness. To this end, PLA was first melt-mixed in a co-rotating twin-screw extruder with up to 40 wt % of different PCL and TPS combinations and then shaped into pieces by injection molding. The mechanical, thermal, and thermomechanical properties of the resultant binary and ternary blend pieces were analyzed and related to their composition. Although the biopolymer blends were immiscible, the addition of both PCL and TPS remarkably increased the flexibility and impact strength of PLA while it slightly reduced its mechanical strength. The most balanced mechanical performance was achieved for the ternary blend pieces that combined high PCL contents with low amounts of TPS, suggesting a main phase change from PLA/TPS (comparatively rigid) to PLA/PCL (comparatively flexible). The PLA-based blends presented an “island-and-sea” morphology in which the TPS phase contributed to the fine dispersion of PCL as micro-sized spherical domains that acted as a rubber-like phase with the capacity to improve toughness. In addition, the here-prepared ternary blend pieces presented slightly higher thermal stability and lower thermomechanical stiffness than the neat PLA pieces. Finally, all biopolymer pieces fully disintegrated in a controlled compost soil after 28 days. Therefore, the inherently low ductility and toughness of PLA can be successfully improved by melt blending with PCL and TPS, resulting in compostable plastic materials with a great potential in, for instance, rigid packaging applications.

scholarly journals Fabrication and Characterization of Biodegradable Composites from Poly (Butylene Succinate-Co-Butylene Adipate) and Taihu Lake Blue Algae

2017 ◽  
Vol 26 (5) ◽  
pp. 096369351702600 ◽  
Author(s):  
Wenjing Xia ◽  
Nianqing Zhu ◽  
Zhongbin Ni ◽  
Mingqing Chen
Keyword(s):  
Tensile Strength ◽  
Taihu Lake ◽  
Mechanical Performance ◽  
Value Added ◽  
Melt Blending ◽  
Butylene Succinate ◽  
Elongation At Break ◽  
Biodegradable Composites ◽  
Thermal Stability Of

Biodegradable composites from poly (butylene succinate-co-butylene adipate) (PBSA) and Taihu Lake (Wuxi, China) blue algae were prepared by melt blending. The property and structure of biocomposites were investigated. By adding extra amount of water to blue algae, the formulated blue algae acted as a plastic in the composites during blending, and exhibited a reinforcing effect on the PBSA matrix. With increasing blue algae content, the thermal stability of the composites decreased; the tensile strength at break and elongation at break of the composites reduced, but the Young's modulus of the composites increased. However, the composite with 30% blue algae loading still exhibited good mechanical performance (tensile strength at break of 21.3 MPa, elongation at break of 180%). The fabrication of value-added PBSA/algae composites appeared as an effective approach to reduce the secondary environmental pollution of Taihu blue algae.

Characterization and Properties of Nucleated Polylactide, Poly(butylene adipate-co-terephthalate), and Thermoplastic Starch Ternary Blend Films: Effects of Compatibilizer and Starch

2013 ◽  
Vol 747 ◽  
pp. 673-677 ◽  
Author(s):  
Worasak Phetwarotai ◽  
Duangdao Aht-Ong
Keyword(s):  
Tensile Properties ◽  
Nucleating Agent ◽  
Thermoplastic Starch ◽  
Ternary Blend ◽  
Screw Extruder ◽  
Elongation At Break ◽  
Blend Films ◽  
Flexible Polymer ◽  
Twin Screw ◽  
Thermal Stability Of

Biodegradable ternary blend films of nucleated polylactide (PLA), poly (butylene adipate-co-terephthalate) (PBAT), and thermoplastic starch (TPS) with the presence of nucleating agent and compatibilizer were prepared via a twin screw extruder. The effects of compatibilizer types and starch contents on the thermal, morphological, and tensile properties of these blend films were evaluated. Two types of compatibilizer (methylene diphenyldiisocyanate (MDI) and polylactide-graft-maleic anhydride (PLA-g-MA)) were used for enhancing an interfacial adhesion of the blends, whereas TPS from tapioca starch was added as a filler at various concentrations (0 to 40 wt%). In addition, talc and PBAT acted as a nucleating agent and a flexible polymer were fixed at 1 phr and 10 wt%, respectively. The results indicated that the thermal stability of the blend films was affected from the presence of compatibilizer and TPS. In addition, the tensile properties and compatibility of PLA, PBAT, and TPS blends were improved with the addition of compatibilizer compared to uncompatibilized blend films as evidenced by SEM results. Furthermore, the blend films with MDI gave higher mechanical properties than those with PLA-g-MA at all compositions. The water absorption of the ternary blend films was evidently increased when the TPS amount was increased; in contrast, tensile strength and elongation at break (EB) of these blend films were significantly decreased.

Processing and Characterization of Palm Fiber-Polypropylene Composites

2011 ◽  
Vol 471-472 ◽  
pp. 145-150
Author(s):  
Ramazan Kahraman ◽  
Sarfraz Abbasi ◽  
Basel Abu-Sharkh
Keyword(s):  
Mechanical Performance ◽  
Mixing Time ◽  
Processing Parameters ◽  
Processing Temperature ◽  
Palm Fiber ◽  
Polypropylene Composites ◽  
Mixing Speed ◽  
Single Screw Extruder ◽  
Injection Molded

Composites of palm fiber and polypropylene were compounded using a mixing device at various temperatures, mixing times, and mixing intensities. Two mixing options were utilized. Either the mixing device was mounted with a mixer or a single screw extruder. The composites were subsequently injection molded into standard tensile specimens for mechanical characterization. Tests were performed to determine the effects of processing parameters such as the mixing and molding temperatures, mixing speed, and mixing time on the mechanical performance of the palm-polypropylene composite. The optimum processing conditions for the mixer were determined to be: Mixing Speed = 50 rpm, Mixing Time = 8 min, and Processing Temperature = 200°C. Optimum extruder conditions, on the other hand, were determined as 40 rpm extruder screw speed and processing temperatures of Zone 1=195°C, Zone 2=200°C, Zone 3=205°C, and Nozzle 210°C. Use of the extruder resulted in higher composite strength with much shorter processing time. Further studies are also being conducted to include coupling agents in the processing to improve the interfacial adhesion between the palm fibers and the polypropylene matrix.

Synthesis and Characterization of LDPE-Carbon Nanotube Composite Foams

2008 ◽  
Author(s):  
Reza Rizvi ◽  
Hani Naguib
Keyword(s):  
Synthesis And Characterization ◽  
Melt Blending ◽  
Composite Foams ◽  
Nucleation Sites ◽  
Twin Screw ◽  
Multi Walled Carbon Nanotubes ◽  
Carbon Nanotube Composite ◽  
Walled Carbon Nanotubes ◽  
Batch Foaming

This study details the synthesis and characterization of composites and composite foams of low-density polyethylene (LDPE) and multi-walled carbon nanotubes (MWCNT). LDPE-MWCNT composites were prepared by melt blending the components in a twin screw compounder and their foams were produced by batch foaming using CO2 as the blowing agent. The composites were characterized for dispersion using SEM and image results indicate good dispersability of MWCNT in LDPE with the formation of a MWCNT network in the LDPE matrix. Thermal and rheological properties of the composites were characterized and results indicate that even a small amount (1 wt.%) of MWCNTs can significantly affect the crystallization kinetics and the rheological behavior. Batch foaming results of the composites depict MWCNTs as heterogeneous nucleation sites for gas bubbles as indicated by the increase in cell density of the composite foams when compared to LDPE foams.

Characterization of citric acid/glycerol co-plasticized thermoplastic starch prepared by melt blending

2007 ◽  
Vol 69 (4) ◽  
pp. 748-755 ◽  
Author(s):  
Rui Shi ◽  
Zizheng Zhang ◽  
Quanyong Liu ◽  
Yanming Han ◽  
Liqun Zhang ◽  
...  
Keyword(s):  
Citric Acid ◽  
Thermoplastic Starch ◽  
Melt Blending

Characterization of Feedstocks for Injection Molded SiCp-Reinforced Al-4.5 wt.%Cu Composite

2011 ◽  
Vol 383-390 ◽  
pp. 3234-3240 ◽  
Author(s):  
Tapany Udomphol ◽  
Benchawan Inpanya ◽  
Nutthita Chuankrerkkul
Keyword(s):  
Injection Molding ◽  
Powder Injection Molding ◽  
Powder Injection ◽  
Solid Loading ◽  
Aluminium Powder ◽  
Twin Screw ◽  
Injection Molded ◽  
Hardness Values ◽  
Potential Use

Characterization of feedstocks for powder injection molding of SiCp-reinforced aluminium composite, as potential use for automotive and light-weight applications, has been studied in this research. Al-4.5 wt.% Cu powder, SiCp and polymeric binder were pre-mixed and compounded using a twin screw extruder at 170oC prior to powder injection molding at 170 oC. Effects of varied solid loadings at 52, 55 and 58% on green properties of the feedstocks have been investigated. Experimental results showed that compounding followed by powder injection molding allowed uniform distribution of SiCp surrounding the aluminium powder. It was found that higher solid loading improved bulk density while hardness values were observed to be similar. Molded specimens of 55% solid loading provided the optimum bend strength and strain at failure. Moreover, it was observed that the opposing abrasive property with angular shape of SiCp resulted in SiCp scratching effect, leading to irregular surface of aluminium powder after injection molding. This consequence and molding porosity were expected to be responsible for relatively low density of the molded specimens, giving the difficulty in molding at higher solid loading.

Preparation and Characterization of Poly(Lactic Acid) (PLA)/Polyoxymethylene (POM) Blends

2018 ◽  
Vol 917 ◽  
pp. 3-6 ◽  
Author(s):  
Muhammad Haniff ◽  
Mohd Bijarimi ◽  
M.S. Zaidi ◽  
Ahmad Sahrim
Keyword(s):  
Tensile Strength ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Chemical Analysis ◽  
Poly Lactic Acid ◽  
Melt Blending ◽  
Screw Extruder ◽  
Elongation At Break ◽  
Twin Screw

PLA has limited applications due to its inherent brittleness, toughness and low elongation at break. One of the options for improvement is through blending with polyoxymethylene (POM). Melt blending of polylactic acid (PLA) and polyoxymethylene (POM) at 90/10 PLA/POM composition was carried out in a twin-screw extruder. The PLA/POM was loaded with 1 – 5 wt.% of nanoclay (Cloisite C20). The blends were then characterized for mechanical, morphological, chemical and thermal properties. It was found that tensile strength, Young's modulus, and elongation at break improved when the loadings of nanoclay were increased. Chemical analysis by FTIR revealed that PLA/POM blend is immiscible.

The Ternary Blends of TPS/PBAT/PLA Films: A Study on the Morphological and Mechanical Properties

2020 ◽  
Vol 861 ◽  
pp. 170-175
Author(s):  
Supanut Phattarateera ◽  
Nantaya Junsook ◽  
Pramote Kumsang ◽  
Ajcharaporn Aontee ◽  
Noppadon Kerddonfag
Keyword(s):  
Mechanical Properties ◽  
Thermoplastic Starch ◽  
Ternary Blend ◽  
Ternary Blends ◽  
Binary Blend ◽  
Soil Burial Test ◽  
Soil Burial ◽  
Blend Films ◽  
Screw Design ◽  
Twin Screw

This study investigated the effect of polylactic acid (PLA) on the mechanical properties and biodegradability of a ternary blend comprising of thermoplastic starch (TPS), Polybutylene adipate terephthalate (PBAT) and PLA. The binary blend (TPS/PBAT) and ternary blend (TPS/PBAT/PLA) with various contents of PLA were prepared through a twin-screw compounding using an intensive mixing screw design. In order to observe the microstructure in blends, the SEM observation revealed the two types of morphology in the blends including (1) some TPS domain that still remained immiscible in all blends and (2) the partially compatible of binary and ternary blends. For the mechanical properties of the blends, the addition of the PLA component led to an improvement of the tensile strength and modulus. For the simple soil burial test, it found that binary film was fully disintegrated within one month, whereas the ternary blend films were also broken down but still remained in small pieces of fragile films. Finally, it can be suggested that the presence of TPS brought to the biodegradation of blends in soil burial test, while incorporating with PLA led to retardation in degradation rate.

Reactive Compatibilization of Polylactide, Thermoplastic Starch and Poly(butylene adipate-co-terephthalate) Biodegradable Ternary Blend Films

2011 ◽  
Vol 695 ◽  
pp. 178-181 ◽  
Author(s):  
Worasak Phetwarotai ◽  
Duangdao Aht-Ong
Keyword(s):  
Tensile Properties ◽  
Thermoplastic Starch ◽  
Interfacial Interaction ◽  
Ternary Blend ◽  
Screw Extruder ◽  
Reactive Compatibilization ◽  
Blend Films ◽  
Reactive Modification ◽  
Twin Screw ◽  
Methylenediphenyl Diisocyanate

Biodegradable blend films of polylactide (PLA), thermoplastic starch (TPS), and poly(butylene adipate-co-terephthalate) (PBAT) were prepared through reactive modification. Three types of compatibilizers, methylenediphenyl diisocyanate (MDI), maleic anhydride (MA), and MA-g-PE, were studied. PLA and PBAT were blended in the presence of the compatibilizer to improve and evaluate the interfacial interaction. PBAT content was varied from 0 to 20 wt%, while compatibilizer content was differed from 0 to 5 wt% based on PBAT amount. For ternary blending, PLA, TPS, and PBAT were melt-blended with and without compatibilizer in a twin screw extruder using glycerol and tapioca starch as plasticizer and filler, respectively. The effects of type and content of compatibilizer and blend compositions on the physical, thermal, morphological, and tensile properties of the films were investigated. The results showed that the blend films with MDI had appropriate physical, thermal, and tensile properties. The presence of small amount of MDI enhanced the thermal and tensile properties of the films compared to the uncompatibilized films. This can be explained by a uniform morphology of the dispersed phase in the PLA matrix.

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