Sericin cocoon bio-compatibilizer for reactive blending of thermoplastic cassava starch

Abstract Cassava starch was blended with glycerol to prepare thermoplastic starch (TPS). TPS was premixed with sericin (TPSS) by solution mixing and then melt-blended with polyethylene grafted maleic anhydride (PEMAH). The effect of sericin on the mechanical properties, morphology, thermal properties, rheology, and reaction mechanism was investigated. The tensile strength and elongation at break of the TPSS10/PEMAH blend were improved to 12.2 MPa and 100.4%, respectively. The TPS/PEMAH morphology presented PEMAH particles (2 µm) dispersed in the TPS matrix, which decreased in size to approximately 200 nm when 5% sericin was used. The melting temperature of PEMAH (121°C) decreased to 111°C because of the small crystal size of the PEMAH phase. The viscosity of TPS/PEMAH increased with increasing sericin content because of the chain extension. Fourier-transform infrared spectroscopy (FTIR) confirmed the reaction between the amino groups of sericin and the maleic anhydride groups of PEMAH. This reaction reduced the interfacial tension between TPS and PEMAH, which improved the compatibility, mechanical properties, and morphology of the blend.

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Sericin cocoon bio-compatibilizer for reactive blending of thermoplastic cassava starch

Scientific Reports ◽

10.1038/s41598-021-99417-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Thanongsak Chaiyaso ◽

Pornchai Rachtanapun ◽

Nanthicha Thajai ◽

Krittameth Kiattipornpithak ◽

Pensak Jantrawut ◽

...

Keyword(s):

Mechanical Properties ◽

Maleic Anhydride ◽

Crystal Size ◽

Thermoplastic Starch ◽

Cassava Starch ◽

Chain Extension ◽

Amino Groups ◽

Reactive Blending ◽

Elongation At Break ◽

Small Crystal Size

AbstractCassava starch was blended with glycerol to prepare thermoplastic starch (TPS). Thermoplastic starch was premixed with sericin (TPSS) by solution mixing and then melt-blended with polyethylene grafted maleic anhydride (PEMAH). The effect of sericin on the mechanical properties, morphology, thermal properties, rheology, and reaction mechanism was investigated. The tensile strength and elongation at break of the TPSS10/PEMAH blend were improved to 12.2 MPa and 100.4%, respectively. The TPS/PEMAH morphology presented polyethylene grafted maleic anhydride particles (2 μm) dispersed in the thermoplastic starch matrix, which decreased in size to approximately 200 nm when 5% sericin was used. The melting temperature of polyethylene grafted maleic anhydride (121 °C) decreased to 111 °C because of the small crystal size of the polyethylene grafted maleic anhydride phase. The viscosity of TPS/PEMAH increased with increasing sericin content because of the chain extension. Fourier-transform infrared spectroscopy confirmed the reaction between the amino groups of sericin and the maleic anhydride groups of polyethylene grafted maleic anhydride. This reaction reduced the interfacial tension between thermoplastic starch and polyethylene grafted maleic anhydride, which improved the compatibility, mechanical properties, and morphology of the blend.

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Structure and Properties of Polyoxymethylene/Silver/Maleic Anhydride-Grafted Polyolefin Elastomer Ternary Nanocomposites

Polymers ◽

10.3390/polym13121954 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1954

Author(s):

Yang Liu ◽

Xun Zhang ◽

Quanxin Gao ◽

Hongliang Huang ◽

Yongli Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Maleic Anhydride ◽

Ag Nanoparticles ◽

Decomposition Temperature ◽

Melt Mixing ◽

Elongation At Break ◽

Maximum Value ◽

Polyolefin Elastomer ◽

Local Defects

In the present study, silver (Ag) nanoparticles and maleic anhydride-grafted polyolefin elastomer (MAH-g-POE) were used as enhancement additives to improve the performance of the polyoxymethylene (POM) homopolymer. Specifically, the POM/Ag/MAH-g-POE ternary nanocomposites with varying Ag nanoparticles and MAH-g-POE contents were prepared by a melt mixing method. The effects of the additives on the microstructure, thermal stability, crystallization behavior, mechanical properties, and dynamic mechanical thermal properties of the ternary nanocomposites were studied. It was found that the MAH-g-POE played a role in the bridging of the Ag nanoparticles and POM matrix and improved the interfacial adhesion between the Ag nanoparticles and POM matrix, owing to the good compatibility between Ag/MAH-g-POE and the POM matrix. Moreover, it was found that the combined addition of Ag nanoparticles and MAH-g-POE significantly enhanced the thermal stability, crystallization properties, and mechanical properties of the POM/Ag/MAH-g-POE ternary nanocomposites. When the Ag/MAH-g-POE content was 1 wt.%, the tensile strength reached the maximum value of 54.78 MPa. In addition, when the Ag/MAH-g-POE content increased to 15wt.%, the elongation at break reached the maximum value of 64.02%. However, when the Ag/MAH-g-POE content further increased to 20 wt.%, the elongation at break decreased again, which could be attributed to the aggregation of excessive Ag nanoparticles forming local defects in the POM/Ag/MAH-g-POE ternary nanocomposites. Furthermore, when the Ag/MAH-g-POE content was 20 wt.%, the maximum decomposition temperature of POM/Ag/MAH-g-POE ternary nanocomposites was 398.22 °C, which was 71.39 °C higher than that of pure POM. However, compared with POM, the storage modulus of POM/Ag/MAH-g-POE ternary nanocomposites decreased with the Ag/MAH-g-POE content, because the MAH-g-POE elastomer could reduce the rigidity of POM.

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Monitoring the degradation of partly decomposable plastic foils

Acta Universitatis Sapientiae Agriculture and Environment ◽

10.2478/ausae-2014-0011 ◽

2014 ◽

Vol 6 (1) ◽

pp. 39-44

Author(s):

Gabriella Rétháti ◽

Krisztina Pogácsás ◽

Tamás Heffner ◽

Barbara Simon ◽

Imre Czinkota ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Molecular Mass ◽

Structural Changes ◽

Thermoplastic Starch ◽

Medium Density ◽

Insulating Layer ◽

Elongation At Break ◽

One Year ◽

The One

Abstract We have monitored the behaviour of different polyethylene foils including virgin medium density polyethylene (MDPE), MDPE containing pro-oxydative additives (238, 242) and MDPE with pro-oxydative additives and thermoplastic starch (297) in the soil for a period of one year. A foil based on a blend of polyester and polylactic acid (BASF Ecovio) served as degradable control. The experiment was carried out by weekly measurements of conductivity and capacity of the soil, since the setup was analogous to a condenser, of which the insulating layer was the foil itself. The twelve replications allowed monthly sampling; the specimen taken out from the soil each month were tested visually for thickness, mechanical properties, morphological and structural changes, and molecular mass. Based on the obtained capacity values, we found that among the polyethylene foils, the one that contained thermoplastic starch extenuated the most. This foil had the greatest decrease in tensile strength and elongation at break due to the presence of thermoplastic starch. The starch can completely degrade in the soil; thus, the foil had cracks and pores. The polyethylene foils that contained pro-oxydant additives showed smaller external change compared to the virgin foil, since there was no available UV radiation and oxygen for their degradation. The smallest change occurred in the virgin polyethylene foil. Among the five examined samples, the commercially available BASF foil showed the largest extenuation and external change, and it deteriorated the most in the soil.

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Crystallization, Structure and Significantly Improved Mechanical Properties of PLA/PPC Blends Compatibilized with PLA-PPC Copolymers Produced by Reactions Initiated with TBT or TDI

Polymers ◽

10.3390/polym13193245 ◽

2021 ◽

Vol 13 (19) ◽

pp. 3245

Author(s):

Lixin Song ◽

Yongchao Li ◽

Xiangyu Meng ◽

Ting Wang ◽

Ying Shi ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Strength ◽

Average Molecular Weight ◽

Toluene Diisocyanate ◽

Chain Extension ◽

Poly Lactic Acid ◽

Cooling Process ◽

Material Degradation ◽

Elongation At Break ◽

Poly Propylene

Poly (lactic acid) (PLA)-Poly (propylene carbonate) (PPC) block copolymer compatibilizers are produced in incompatible 70wt%PLA/PPC blend by initiating transesterification with addition of 1% of tetra butyl titanate (TBT) or by chain extension with addition of 2% of 2,4-toluene diisocyanate (TDI). The above blends can have much better mechanical properties than the blend without TBT and TDI. The elongation at break is dramatically larger (114% with 2% of TDI and 60% with 1% of TBT) than the blend without TDI and TBT, with a slightly lower mechanical strength. A small fraction of the copolymer is likely formed in the PLA/PPC blend with addition of TBT, and a significant amount of the copolymer can be made with addition of TDI. The copolymer produced with TDI has PPC as a major content (~70 wt%) and forms a miscible interphase with its own Tg. The crystallinity of the blend with TDI is significantly lower than the blend without TDI, as the PLA blocks of the copolymer in the interphase is hardly to crystallize. The average molecular weight increases significantly with addition of TDI, likely compensating the lower mechanical strength due to lower crystallinity. Material degradation can occur with addition of TBT, but it is very limited with 1% of TBT. However, compared with the blends without TBT, the PLA crystallinity of the blend with 1%TBT increases sharply during the cooling process, which likely compensates the loss of mechanical strength due to the slightly material degradation. The added TDI does not have any significant impact on PLA lamellar packing, but the addition of TBT can make PLA lamellar packing much less ordered, presumably resulted from much smaller PPC domains formed in the blend due to better compatibility.

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Bio-Based Thermoplastic Starch Composites Reinforced by Dialdehyde Lignocellulose

Molecules ◽

10.3390/molecules25143236 ◽

2020 ◽

Vol 25 (14) ◽

pp. 3236

Author(s):

Peng Yin ◽

Wen Zhou ◽

Xin Zhang ◽

Bin Guo ◽

Panxin Li

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Tensile Strength ◽

Water Resistance ◽

Thermoplastic Starch ◽

Contact Angles ◽

Sem Images ◽

Elongation At Break ◽

Injection Process ◽

Oxidation Damage

In order to improve the mechanical properties and water resistance of thermoplastic starch (TPS), a novel reinforcement of dialdehyde lignocellulose (DLC) was prepared via the oxidation of lignocellulose (LC) using sodium periodate. Then, the DLC-reinforced TPS composites were prepared by an extrusion and injection process using glycerol as a plasticizer. The DLC and LC were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the effects of DLC content on the properties of the DLC/TPS composites were investigated via the evaluation of SEM images, mechanical properties, thermal stability, and contact angles. XRD showed that the crystallinity of the DLC decreased due to oxidation damage to the LC. SEM showed good dispersion of the DLC in the continuous TPS phase at low amounts of DLC, which related to good mechanical properties. The tensile strength of the DLC/TPS composite reached a maximum at a DLC content of 3 wt.%, while the elongation at break of the DLC/TPS composites increased with increasing DLC content. The DLC/TPS composites had better thermal stability than the neat TPS. As the DLC content increased, the water resistance first increased, then decreased. The highest tensile strength and elongation at break reached 5.26 MPa and 111.25%, respectively, and the highest contact angle was about 90.7°.

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Effect of Co60γ Ray Irradiation on Thermoplastic Corn Starch Plastic

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.772.34 ◽

2013 ◽

Vol 772 ◽

pp. 34-37

Author(s):

Hao Tang ◽

Hai Tian Jiang ◽

Bin Guo ◽

Pan Xin Li

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Corn Starch ◽

Irradiation Time ◽

Thermoplastic Starch ◽

Endothermic Peak ◽

Macromolecular Structure ◽

Thermal And Mechanical Properties ◽

Elongation At Break ◽

Γ Ray

Corn starch was irradiated by 60Coγ ray, and then the thermoplastic starch plastic (TPS) was prepared by adding glycerol. Microstructure, thermal and mechanical properties of the corn starch and starch plastic were studied in details by FTIR, DSC and SEM. Results showed that the starch macromolecular structure was damaged by irradiation, and with increased irradiation time, the temperature of melt endothermic peak and tensile strength decreased, elongation at break increases for starch plastic, the thermoplastic property of starch was enhanced obviously.

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Preparation and Properties of Sponge Rubber Based on Natural Rubber and Cassava Starch

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.931-932.68 ◽

2014 ◽

Vol 931-932 ◽

pp. 68-72

Author(s):

Komsun Temna ◽

Nitinart Saetung ◽

Anuwat Saetung

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Natural Rubber ◽

Cassava Starch ◽

Interfacial Interaction ◽

Morphological Properties ◽

Elongation At Break ◽

Cure Time ◽

The Difference ◽

Cure Characteristic

In this work, the sponge rubbers based on cassava starch masterbatch in latex phase with the difference technique (non-gelatinized and gelatinized cassava starch) were preformed. The cassava starch contents from 0 to 70 phr were also studied. The cure characteristic, mechanical and morphological properties were investigated. It was found that the scorch time and cure time were increased with an increasing of cassava starch contents in both techniques. The mechanical properties i.e., tensile strength, elongation at break and tear strength were decreased with an increasing of cassava starch contents, except 500% modulus. However, the sponge based on gelatinized technique gave the better mechanical properties than that of non-gelatinized cassava starch. The SEM micrographs of sponge NR from gelatinized technique were also able to confirm a good interfacial interaction between hydrophilic cassava starch and hydrophobic NR.

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Mechanical Properties of Thermoplastic Starch Biocomposite Films with Hybrid Fillers

Journal of Physics Conference Series ◽

10.1088/1742-6596/2080/1/012011 ◽

2021 ◽

Vol 2080 (1) ◽

pp. 012011

Author(s):

Di Sheng Lai ◽

Sinar Arzuria Adnan ◽

Azlin Fazlina Osman ◽

Ismail Ibrahim ◽

Hazrul Haq

Keyword(s):

Mechanical Properties ◽

Food Packaging ◽

Corn Starch ◽

Composite Films ◽

Thermoplastic Starch ◽

Elongation At Break ◽

Biocomposite Films ◽

Hybrid Fillers ◽

The Matrix ◽

Dry Food

Abstract Thermoplastic starch (TPS) was studied extensively to replace conventional plastic in packaging application. In this study, granule corn starch was first plasticized with water and glycerol to form TPS films and two different fillers were incorporated with TPS to form hybrid biocomposite films (TPSB). Two different fillers: Microcrystalline cellulose (MC) and Nano bentonite (NB) fixed at 1: 4 ratios in various loading (1wt%-6wt%) were incorporated in TPS to study effect of hybrid fillers on the mechanical properties of TPSB films. The effect of different loading of MC/NB on TPSB films was investigated through the structural, morphological and mechanical testing. Fourier Transform Infrared Spectroscopy (FTIR) shows TPS matrix and hybrid fillers are highly compatible due to hydroxyl bonding and verified through the shifting of spectra band. Scanning Electron Microscope (SEM) showed even distribution of fillers in the matrix of TPS. The TPSB films exhibited significant improvement 40% in elongation at break compared to pure TPS films. In this study, 5wt% is best loading of the hybrid fillers to incorporated in TPSB films as it achieved the highest value of tensile strength (8.52MPa), Young’s Modulus (42.0 MPa) and elongation at break (116.3%). Generally, previous studies showed flexibility of TPS composite films reduced with incorporating filler, however in this study, the flexibility TPSB show significant improvement compared to previous studies and exhibit promising potential in dry food packaging application.

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Corn Starch Reactive Blending with Latex from Natural Rubber in Presence of Na+ Ions of Carboxymethyl Cellulose as a Catalyst

10.21203/rs.3.rs-737762/v1 ◽

2021 ◽

Author(s):

Noppol Leksawasdi ◽

Thanongsak Chaiyaso ◽

Pornchai Rachtanapun ◽

Pensak Jantrawut ◽

Warintorn Ruksiriwanich ◽

...

Keyword(s):

Mechanical Properties ◽

Contact Angle ◽

Natural Rubber ◽

Carboxymethyl Cellulose ◽

Corn Starch ◽

Carboxyl Groups ◽

Reactive Blending ◽

Swelling Properties ◽

Elongation At Break ◽

Na Ions

Abstract Corn starch (CS) was blended with glycerol, latex natural rubber (LNR), and carboxymethyl cellulose (CMC). The addition of 10 phr of CMC improved the Young’s modulus (6.7 MPa), tensile strength (8 MPa), and elongation at break (80%) of the CSG/LNR blend. The morphology of the CSG/LNR/CMC blends showed a uniform distribution of LNR particles (1–3 µm) in the CSG matrix. The addition of CMC enhanced the swelling ability and water droplet contact angle of the blends owing to the swelling properties, interfacial crosslinking, and amphiphilic structure of CMC. Fourier transform infrared spectroscopy confirmed the reaction between the C=C bond of LNR and the carboxyl groups (–COO-) of CMC, in which Na+ ions in CMC acted as a catalyst. Notably, the mechanical properties of the CSG/LNR/CMC blend were improved owing to the miscibility of CSG/CMC and the CMC/LNR interfacial reaction.

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Corn starch reactive blending with latex from natural rubber using Na+ ions augmented carboxymethyl cellulose as a crosslinking agent

Scientific Reports ◽

10.1038/s41598-021-98807-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Noppol Leksawasdi ◽

Thanongsak Chaiyaso ◽

Pornchai Rachtanapun ◽

Sarinthip Thanakkasaranee ◽

Pensak Jantrawut ◽

...

Keyword(s):

Mechanical Properties ◽

Natural Rubber ◽

Carboxymethyl Cellulose ◽

Corn Starch ◽

Crosslinking Agent ◽

Medical Applications ◽

Reactive Blending ◽

Swelling Properties ◽

Elongation At Break ◽

Na Ions

AbstractA mixture of corn starch and glycerol plasticizer (CSG) was blended with latex natural rubber (LNR) and carboxymethyl cellulose (CMC). The addition of 10 phr of CMC improved the Young’s modulus (6.7 MPa), tensile strength (8 MPa), and elongation at break (80%) of the CSG/LNR blend. The morphology of the CSG/LNR/CMC blends showed a uniform distribution of LNR particles (1–3 µm) in the CSG matrix. The addition of CMC enhanced the swelling ability and water droplet contact angle of the blends owing to the swelling properties, interfacial crosslinking, and amphiphilic structure of CMC. Fourier transform infrared spectroscopy confirmed the reaction between the C=C bond of LNR and the carboxyl groups (–COO−) of CMC, in which the Na+ ions in CMC acted as a catalyst. Notably, the mechanical properties of the CSG/LNR/CMC blend were improved owing to the miscibility of CSG/CMC and the CMC/LNR interfacial reaction. The CSG/LNR/CMC biodegradable polymer with high mechanical properties and interfacial tension can be used for packaging, agriculture, and medical applications.

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