Conductive Thermoplastic Starch (TPS) Composite Filled with Waste Iron Filings

A thermoplastic starch (TPS) was produced, starting with potato starch, glycerol and acetic acid, to shape it in films of thickness around 100 microns. To TPS iron waste filing particles, in the amount of 12% the weight of starch, were introduced in different modalities: as received, reduced in size by the use of a mortar, after treatment with hydrochloric acid, and after treatment and removal of hydrochloric acid. Morphological studies were carried out by optical and scanning electron microscopy and illustrated that the dispersion of iron filings was not optimal, though some improvement was observed by a reduced dimension of the particles. Tensile tests indicated the considerable improvement of stiffness offered by the insertion of iron particles to TPS, although the ultimate strain was reduced to less than 10%. Thermal characterization using thermogravimetry allowed revealing the three typical peaks for potato starch degradation, with only a slight decrease due to iron introduction. EDS allowed evaluating the presence of impurities in the iron filings and evidenced that the presence of iron was more effective on the surface than in the rest of the film. As a final consideration, An improvement in electrical conductivity by over an order of magnitude was obtained by the TPS+Fe+HCl film with respect to pure TPS.

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Thermoplastic Starch Films Added with Dry Nopal (Opuntia Ficus Indica) Fibers

Fibers ◽

10.3390/fib7110099 ◽

2019 ◽

Vol 7 (11) ◽

pp. 99 ◽

Cited By ~ 3

Author(s):

Fabrizio Scognamiglio ◽

Daniele Mirabile Gattia ◽

Graziella Roselli ◽

Franca Persia ◽

Ugo De Angelis ◽

...

Keyword(s):

Potato Starch ◽

Tensile Tests ◽

Thermoplastic Starch ◽

Morphological Characterization ◽

Scanning Calorimetry ◽

Opuntia Ficus Indica ◽

Positive Effects ◽

Manufacturing Procedure ◽

Starch Films ◽

Mechanical Tensile

Dry fibers coming from garden waste, originating from Opuntia ficus indica, were introduced in amounts of either 8 or 16 wt % into a self-produced thermoplastic starch (TPS) based on potato starch and glycerol. Thermal (differential scanning calorimetry, DSC), mechanical (tensile tests), and morphological characterization with scanning electron microscopy (SEM) and performing energy-dispersive X-ray spectrometry (microanalysis) were carried out. The results indicated that the uneven distribution and variable geometry of fibers introduced led to a reduction of tensile stress and strain with respect to pure TPS. However, the positive effects of prolonged mixing and increased thickness were highlighted, which suggest the fabrication of the composite could be improved in the future by controlling the manufacturing procedure.

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Thermoplastic Starch (TPS) Films Added with Mucilage from Opuntia Ficus Indica: Mechanical, Microstructural and Thermal Characterization

Materials ◽

10.3390/ma13041000 ◽

2020 ◽

Vol 13 (4) ◽

pp. 1000 ◽

Cited By ~ 2

Author(s):

Fabrizio Scognamiglio ◽

Daniele Mirabile Gattia ◽

Graziella Roselli ◽

Franca Persia ◽

Ugo De Angelis ◽

...

Keyword(s):

Mechanical Performance ◽

Potato Starch ◽

Thermal Characterization ◽

Thermoplastic Starch ◽

Vegetable Waste ◽

Scanning Calorimetry ◽

Plasticization Effect ◽

Magnesium Salts ◽

The One ◽

Loading Modes

Opuntia cladodes are a typical vegetable waste, from which mucilage in gel form can be extracted. This work proposes blending it with a self-produced thermoplastic starch (TPS), originating from potato starch with a high content in glycerol (ca. 30%). Three methods were compared for extraction, bare maceration (MA), mechanical blending (ME) and mechanical blending following maceration (MPM) to produce films with an approximate thickness of 150 μm. For the comparison, tensile testing, differential scanning calorimetry and scanning electron microscopy were used. The MPM process proved the most effective, not only for extraction yielding, but also to obtain a larger deformation of the samples with respect to the one allowed by the pure TPS films. A considerable plasticization effect was observed. Despite this, the mechanical performance is still not completely satisfactory, and the expected effect of the calcium and magnesium salts contained in the mucilage to improve the rigidity of the TPS film was not really revealed. Prospected improvements would concern the fabrication process and the investigation of other possible loading modes and sample geometries.

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Electrochemical and Surface Morphological Studies of Carbon Steel Corrosion by a Novel Polynuclear Schiff Base in HCl Solution

ISRN Electrochemistry ◽

10.1155/2013/820548 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

K. S. Shaju ◽

K. Joby Thomas ◽

Vinod P. Raphael ◽

Aby Paul

Keyword(s):

Weight Loss ◽

Schiff Base ◽

Carbon Steel ◽

Hydrochloric Acid ◽

Adsorption Isotherm ◽

Acid Solution ◽

Corrosion Inhibition ◽

Hydrochloric Acid Solution ◽

Inhibition Efficiency ◽

Morphological Studies

The corrosion inhibition efficiency of a potential polynuclear Schiff base, (s)-2-(anthracene-9 (10H)-ylidene amino)-5-guanidinopentanoic acid (A9Y5GPA), on carbon steel (CS) in 1 M hydrochloric acid solution has been investigated using weight loss measurements, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization studies. The corrosion inhibition efficiencies of parent amine [(s)-2-amino-5-guanidinopentanoic acid] and parent ketone (anthracene-9 (10H)-one) on carbon steel in 1.0 M hydrochloric acid solution have also been investigated using weight loss studies. The electrochemical and weight loss data established that the inhibition efficiency on CS increases with the increase in the concentration of inhibitor, A9Y5GPA. The adsorption of A9Y5GPA obeys the Langmuir adsorption isotherm. Thermodynamic parameters (Kads, ΔGads0) were calculated using the adsorption isotherm. Activation parameters of the corrosion process (Ea, ΔH* and ΔS*) were also calculated from the corrosion rates obtained from temperature studies. Tafel plot analysis revealed that A9Y5GPA acts as a mixed-type inhibitor. A probable inhibition mechanism was also proposed. Surface morphology of the carbon steel specimens in the presence and absence of the inhibitor was evaluated by SEM analysis.

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Variability of Mechanical Properties of Collagen Membranes used in Dentistry

Materiale Plastice ◽

10.37358/mp.18.4.5059 ◽

2018 ◽

Vol 55 (4) ◽

pp. 488-493

Author(s):

Loredana Santo ◽

Fabrizio Quadrini ◽

Denise Bellisario ◽

Antonella Polimeni ◽

Anna Santarsiero

Keyword(s):

Stress Relaxation ◽

Tensile Tests ◽

Mechanical Analysis ◽

Mechanical Tests ◽

Static Behavior ◽

Density Measurements ◽

Dynamic Mechanical ◽

Dependent Behavior ◽

Order Of Magnitude ◽

Collagen Membranes

The aim of this study is proposing a combination of measurements to assess the functional variability of collagen membranes used in Guided Bone Regeneration (GBR) and Guided Tissue Regeneration (GTR) techniques. As far as clinical applications are concerned, a proper qualification is critical when deciding, among commercially available collagen membranes, upon the most appropriate one for each specific clinical case. Two commercially available collagen membranes, namely Collprotect� and Jason�, were considered for the experimentation. After thickness and density measurements, the quasi-static behavior was studied for both membranes by means of conventional mechanical tests, i.e. tear and tensile tests, whereas their time-dependent behavior was evaluated by means of stress relaxation tests and dynamic mechanical analysis. Collagen membranes showed an elevated among samples variability. The variability within the same kind of membrane is of the same order of magnitude of the between membrane kinds variability. All the membranes showed strong time dependence both in stress relaxation and in dynamic mechanical tests. This fact should be taken under consideration for the membrane final application.

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Mechanical and thermal characterization of a beet pulp-starch composite for building applications

E3S Web of Conferences ◽

10.1051/e3sconf/20198508005 ◽

2019 ◽

Vol 85 ◽

pp. 08005

Author(s):

Hamzé Karpaky ◽

Chadi Maalouf ◽

Christophe Bliard ◽

Alexandre Gacoin ◽

Mohammed Lachi ◽

...

Keyword(s):

Thermal Conductivity ◽

Sugar Beet ◽

Building Materials ◽

Potato Starch ◽

Starch Content ◽

Compressive Strain ◽

Thermal Inertia ◽

Thermal Characterization ◽

Sugar Beet Pulp ◽

Beet Pulp

This work shows the making of a new bio-based material for building insulation from sugar beet pulp and potato starch. The material is both lightweight and ecofriendly. The influence of starch/ sugar beet pulp ratio (S/BP) is studied. Four binder mass dosages are considered, 10, 20, 30 and 40% (relative to the beet pulp). Samples are characterized in terms of absolute and bulk density, compressive and flexural strength, as well as thermal properties (thermal conductivity and thermal inertia). The compressive strength increases linearly with the S/BP mass ratio to reach 0.52 MPa and the compressive strain is 30%. The thermal conductivity is to around 0.070 W/m. K. The results obtained shows that increasing starch amount tends to decrease composite porosity but increases thermal conductivity and mechanical properties. Depending on the starch content, beet pulp composites have a good thermal and can be used as building materials.

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On-Chip Thermal Insulation Using Porous GaN

Proceedings ◽

10.3390/proceedings2130776 ◽

2018 ◽

Vol 2 (13) ◽

pp. 776 ◽

Cited By ~ 2

Author(s):

Bogdan F. Spiridon ◽

Peter H. Griffin ◽

John C. Jarman ◽

Yingjun Liu ◽

Tongtong Zhu ◽

...

Keyword(s):

Thermal Insulation ◽

High Speed ◽

Thermal Characterization ◽

Semiconductor Materials ◽

3Ω Method ◽

Theoretical Predictions ◽

Order Of Magnitude ◽

On Chip ◽

Fundamental Requirement

This study focuses on the thermal characterization of porous gallium nitride (GaN) usingan extended 3ω method. Porous semiconductor materials provide a solution to the need for on-chipthermal insulation, a fundamental requirement for low-power, high-speed and high-accuracythermal sensors. Thermal insulation is especially important in GaN devices, due to the intrinsicallyhigh thermal conductivity of the material. The results show one order of magnitude reduction inthermal conductivity, from 130 W/mK to 10 W/mK, in line with theoretical predictions for porousmaterials. This achievement is encouraging in the quest for integrating sensors with opto-, powerandRF-electronics on a single GaN chip.

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Influence of Starch Composition and Molecular Weight on Physicochemical Properties of Biodegradable Films

Polymers ◽

10.3390/polym11071084 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1084 ◽

Cited By ~ 17

Author(s):

Daniel Domene-López ◽

Juan Carlos García-Quesada ◽

Ignacio Martin-Gullon ◽

Mercedes G. Montalbán

Keyword(s):

Molecular Weight ◽

Corn Starch ◽

Amylose Content ◽

Potato Starch ◽

Thermoplastic Starch ◽

Grain Structure ◽

Rice Starch ◽

Hydration Properties ◽

Casting Technique ◽

Starch Films

Thermoplastic starch (TPS) films are considered one of the most promising alternatives for replacing synthetic polymers in the packaging field due to the starch biodegradability, low cost, and abundant availability. However, starch granule composition, expressed in terms of amylose content and phosphate monoesters, and molecular weight of starch clearly affects some film properties. In this contribution, biodegradable TPS films made from potato, corn, wheat, and rice starch were prepared using the casting technique. The effect of the grain structure of each starch on microstructure, transparency, hydration properties, crystallinity, and mechanical properties of the films, was evaluated. Potato starch films were the most transparent and corn starch films the most opaque. All the films had homogeneous internal structures—highly amorphous and with no pores, both of which point to a good starch gelatinization process. The maximum tensile strength (4.48–8.14 MPa), elongation at break (35.41–100.34%), and Young’s modulus (116.42–294.98 MPa) of the TPS films were clearly influenced by the amylose content, molecular weight, and crystallinity of the film. In this respect, wheat and corn starch films, are the most resistant and least stretchable, while rice starch films are the most extensible but least resistant. These findings show that all the studied starches can be considered suitable for manufacturing resistant and flexible films with similar properties to those of synthetic low-density polyethylene (LDPE), by a simple and environmentally-friendly process.

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Blend of cassava starch and high-density polyethylene with green tea for food packaging

Polymers from Renewable Resources ◽

10.1177/2041247920952641 ◽

2020 ◽

Vol 11 (1-2) ◽

pp. 3-14

Author(s):

Cassiano MN Romagnolli ◽

Gabriela P Leite ◽

Tiago AR Rodrigues ◽

Carolina L Morelli

Keyword(s):

Green Tea ◽

High Density Polyethylene ◽

Food Packaging ◽

Antibacterial Properties ◽

Food Products ◽

Tensile Tests ◽

Thermoplastic Starch ◽

Active Packaging ◽

High Density ◽

Service Lifetime

Plastic packagings are widely used for several food products. Considering the relatively short service lifetime of this application, it is important to perceive in the search of eco-friendly alternatives to this market, such as polymers from renewable sources, as thermoplastic starch and “green” polyethylene. The incorporation of an antibacterial agent to the packaging can extend food shelf life. Camellia sinensis is a plant with known antibacterial properties used in the preparation of “green tea.” In the present work, green tea was incorporated to a blend of cassava thermoplastic starch and high-density polyethylene (HDPE) by melt extrusion, aiming application as active packaging. Films were obtained by thermopressing and characterized through infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and tensile tests. Their antibacterial properties were evaluated against Staphylococcus aureus and Escherichia coli. The results indicated that the material developed has potential for food packaging applications. Moreover, the methodology applied for green tea incorporation in the Starch/HDPE films can be extended for many extracts from natural components, contributing to the advancement of research in the development of active packaging for food products. To the best of our knowledge, no previous work studied the properties of starch/HDPE blend with green tea.

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