Effect of starch structure on the processing, mechanical properties and biodegradability of thermoplastic starch films

Nano montmorillonite (MMT) was modified by low molecular weight polylactic acid (PLA), then, the PLA modified MMT and raw MMT were added into thermoplastic starch (TPS) to prepare biodegradable nanocomposite films, respectively. For both nanocomposite films with raw MMT and modified MMT, the Tmax of degradation was enhanced and the mechanical properties were improved. The composite films containing 4 wt.% MMT displayed tensile strength of 5.06 MPa, approximately 1.4 times of that for the pure TPS films. The tensile strength of composite films containing 4 wt.% modified MMT is 6.74 MPa approximately 2 times of those for pure starch films. On the other hand, the composite film containing 4 wt.% modified MMT displayed elongation at break as high as 34.25%, which is 1.3 times of that of the pure starch film, while the composite films containing raw MMT had reduced elongation at break. This study showed that the MMT modified with PLA could significantly enhance the mechanical properties of TPS, and provides a new method to prepare fully biodegradable starch-based nanocomposites.

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Influence of water addition on mechanical properties of thermoplastic starch foils

International Agrophysics ◽

10.1515/intag-2015-0031 ◽

2015 ◽

Vol 29 (3) ◽

pp. 267-273 ◽

Cited By ~ 7

Author(s):

Dariusz Chocyk ◽

Bożena Gładyszewska ◽

Anna Ciupak ◽

Tomasz Oniszczuk ◽

Leszek Mościcki ◽

...

Keyword(s):

Mechanical Properties ◽

Rotation Speed ◽

Potato Starch ◽

Young Modulus ◽

Thermoplastic Starch ◽

Breaking Force ◽

Water Addition ◽

Influence Of Water ◽

Starch Films ◽

Extrusion Method

Abstract The aim of this paper is to study the influence of water on the mechanical properties of thermoplastic starch films. Experimental observations of Young modulus and the breaking force of thermoplastic starch foils with different percentages of polyvinyl alcohol and keratin additives and screw rotation speeds are reported. Thermoplastic starch foils are prepared by the extrusion method with the bowling from potato starch and glycerol as a plasticizer. Young modulus and the breaking force were determined by the random marker method. Measurements of Young modulus and the breaking force of the films were performed after their production and after dosing with water. It was observed that in all cases Young modulus decreases after dosing with water, but the breaking force lied in the same range. Thermoplastic starch foils produced at the screw rotation speed equal to 60 r.p.m. have the best mechanical properties. The highest value of Young modulus and the breaking force were obtained for samples with a 1% keratin additive.

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Starch/Poly (Glycerol-Adipate) Nanocomposite Film as Novel Biocompatible Materials

Coatings ◽

10.3390/coatings9080482 ◽

2019 ◽

Vol 9 (8) ◽

pp. 482 ◽

Cited By ~ 1

Author(s):

Sagnelli ◽

Cavanagh ◽

Xu ◽

Swainson ◽

Blennow ◽

...

Keyword(s):

Mechanical Properties ◽

Glass Transition ◽

Thermoplastic Starch ◽

Nanocomposite Films ◽

Great Promise ◽

Hybrid Nanocomposite ◽

Biocompatible Material ◽

The Earth ◽

Biodegradable Scaffolds ◽

Starch Films

Starch is one of the most abundant polysaccharides on the earth and it is the most important source of energy intake for humans. Thermoplastic starch (TPS) is also widely used for new bio-based materials. The blending of starch with other molecules may lead to new interesting biodegradable scaffolds to be exploited in food, medical, and pharmaceutical fields. In this work, we used native starch films as biopolymeric matrix carriers of chemo enzymatically-synthesized poly (glycerol-adipate) (PGA) nanoparticles (NPs) to produce a novel and biocompatible material. The prototype films had a crystallinity ranging from 4% to 7%. The intrinsic and thermo-mechanical properties of the composite showed that the incorporation of NPs in the starch films decreases the glass transition temperature. The utilization of these film prototypes as the basis for new biocompatible material showed promise, particularly because they have a very low or even zero cytotoxicity. Coumarin was used to monitor the distribution of the PGA NPs in the films and demonstrated a possible interaction between the two polymers. These novel hybrid nanocomposite films show great promise and could be used in the future as biodegradable and biocompatible platforms for the controlled release of amphiphilic and hydrophobic active ingredients.

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Study of the Preparation and Properties of TPS/PBSA/PLA Biodegradable Composites

Journal of Composites Science ◽

10.3390/jcs5020048 ◽

2021 ◽

Vol 5 (2) ◽

pp. 48

Author(s):

Yuxuan Wang ◽

Yuke Zhong ◽

Qifeng Shi ◽

Sen Guo

Keyword(s):

Mechanical Properties ◽

Heat Resistance ◽

Thermoplastic Starch ◽

Sem Analysis ◽

Infrared Spectrometry ◽

Fourier Transform Infrared Spectrometry ◽

Melt Mixing ◽

Two Phase ◽

Biodegradable Composites ◽

Phase Compatibility

Thermoplastic starch/butyl glycol ester copolymer/polylactic acid (TPS/PBSA/PLA) biodegradable composites were prepared by melt-mixing. The structure, microstructure, mechanical properties and heat resistance of the TPS/PBSA/PLA composites were studied by Fourier-transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), tensile test and thermogravimetry tests, respectively. The results showed that PBSA or PLA could bind to TPS by hydrogen bonding. SEM analysis showed that the composite represents an excellent dispersion and satisfied two-phase compatibility when the PLA, TPS and PBSA blended by a mass ration of 10, 30, and 60. The mechanical properties and the heat resistance of TPS/PBSA/PLA composite were improved by adding PLA with content less than 10%, according to the testing results.

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Ecofriendly Preparation and Characterization of a Cassava Starch/Polybutylene Adipate Terephthalate Film

Processes ◽

10.3390/pr8030329 ◽

2020 ◽

Vol 8 (3) ◽

pp. 329

Author(s):

Tan Yi ◽

Minghui Qi ◽

Qi Mo ◽

Lijie Huang ◽

Hanyu Zhao ◽

...

Keyword(s):

Mechanical Properties ◽

Contact Angle ◽

Water Vapor ◽

Composite Film ◽

Water Absorption ◽

Composite Films ◽

Thermoplastic Starch ◽

Light Transmittance ◽

Infrared Spectrometry ◽

Nano Zno

Composite films of polybutylene adipate terephthalate (PBAT) were prepared by adding thermoplastic starch (TPS) (TPS/PBAT) and nano-zinc oxide (nano-ZnO) (TPS/PBAT/nano-ZnO). The changes of surface morphology, thermal properties, crystal types and functional groups of starch during plasticization were analyzed by scanning electron microscopy, synchronous thermal analysis, X-ray diffraction, infrared spectrometry, mechanical property tests, and contact Angle and transmittance tests. The relationship between the addition of TPS and the tensile strength, transmittance, contact angle, water absorption, and water vapor barrier of the composite film, and the influence of nano-ZnO on the mechanical properties and contact angle of the 10% TPS/PBAT composite film. Experimental results show that, after plasticizing, the crystalline form of starch changed from A-type to V-type, the functional group changed and the lipophilicity increased; the increase of TPS content, the light transmittance and mechanical properties of the composite membrane decreased, while the water vapor transmittance and water absorption increased. The mechanical properties of the composite can be significantly improved by adding nano-ZnO at a lower concentration (optimum content is 1 wt%).

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Water sorption and mechanical properties of cassava starch films and their relation to plasticizing effect

Carbohydrate Polymers ◽

10.1016/j.carbpol.2005.01.003 ◽

2005 ◽

Vol 60 (3) ◽

pp. 283-289 ◽

Cited By ~ 352

Author(s):

S. Mali ◽

L.S. Sakanaka ◽

F. Yamashita ◽

M.V.E. Grossmann

Keyword(s):

Mechanical Properties ◽

Water Sorption ◽

Cassava Starch ◽

Starch Films

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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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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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