Effect of thermo-alkali treatment on the morphological and electrochemical properties of biopolymer electrolytes based on corn starch–Al(OH)3

Background: Solid biopolymer electrolytes are a type of material with high technological potential used in the development of solar cells, batteries, fuel cells, among others, due to their biodegradable nature and low environmental impact. Aim: This study aimed to evaluate the effect of the botanical origin of the starch used to prepare solid biopolymeric electrolyte films on its electrochemical and thermal properties and to establish the variations in thermal decomposition temperatures and redox potentials depending on the botanical origin of the starch used. Methods: Films of solid biopolymer electrolyte were made by thermochemical synthesis processes using corn starch, cassava starch, potato starch, glycerol, polyethylene glycol, and glutaraldehyde as plasticizers and lithium perchlorate salt. The synthesis solutions were taken to an oven at 70 °C for 48 hours. The films were characterized electrochemically by cyclic voltammetry using a dry electrochemical cell and thermally by differential scanning calorimetry and thermogravimetric analysis. Results and Discussion: The results showed that the electrochemical behavior of the films was similar in terms of registered redox processes. However, the potential values of the oxidation and reduction were different, as are the stability and intensity of the processes. On the other hand, the thermal analysis allowed establishing two decomposition processes in each of the films studied; the first process was due to dehydration and depolymerization phenomena in the films. The temperatures recorded were 59.0 °C, 58.9 °C, and 89.9 °C for potato starch, cassava starch, and corn starch films. The second process evidenced the thermal decomposition at different temperatures, 267.7 °C in potato starch films, 280.6 °C in corn starch films, and 287.1 °C in cassava starch films. Conclusions: It could be concluded that the botanical origin of the starch used in the synthesis of solid biopolymer electrolyte films affects its behavior and electrochemical and thermal stability.

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Morphology, composition and electrochemical properties of bioactive-TiO2/HA on CP-Ti and Ti6Al4V substrates fabricated by alkali treatment of hybrid plasma electrolytic oxidation process (estimation of porosity from EIS results)

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2019.07.032 ◽

2019 ◽

Vol 375 ◽

pp. 266-291 ◽

Cited By ~ 11

Author(s):

H. Fakhr Nabavi ◽

M. Aliofkhazraei

Keyword(s):

Electrochemical Properties ◽

Plasma Electrolytic Oxidation ◽

Oxidation Process ◽

Alkali Treatment ◽

Electrolytic Oxidation ◽

Hybrid Plasma ◽

Plasma Electrolytic ◽

Cp Ti

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Effects of different iodide salts on the electrical and electrochemical properties of hybrid biopolymer electrolytes for dye-sensitized solar cells application

Polymer Bulletin ◽

10.1007/s00289-021-03980-8 ◽

2021 ◽

Author(s):

M. S. A. Rani ◽

S. Rudhziah ◽

A. Ahmad ◽

N. S. Mohamed

Keyword(s):

Solar Cells ◽

Electrochemical Properties ◽

Dye Sensitized Solar Cells ◽

Dye Sensitized ◽

Biopolymer Electrolytes ◽

Sensitized Solar Cells

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Influence of Alkali Treatment on Mechanical Properties of Poly Lactic Acid Bamboo Fiber Green Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1110.56 ◽

2015 ◽

Vol 1110 ◽

pp. 56-59 ◽

Cited By ~ 1

Author(s):

Shoma Maruyama ◽

Hitoshi Takagi ◽

Yoshitoshi Nakamura ◽

Antonio Norio Nakagaito ◽

Chizuru Sasaki

Keyword(s):

Corn Starch ◽

Alkali Treatment ◽

Natural Fibers ◽

Bamboo Fiber ◽

Poly Lactic Acid ◽

Green Composites ◽

Pressing Method ◽

The Matrix ◽

Materials Research ◽

Bamboo Fibers

In recent years, in order to reduce the environmental burden of composite materials, research has been conducted to develop composites made from plant-derived polymers and natural fibers, the so called green composites. In this study, green composites were made from polylactic acid (PLA), a bioplastic derived from corn starch, reinforced with bamboo fibers. The composites were manufactured by mixing short bamboo fibers and dispersion-type PLA resin. Subsequently, PLA/bamboo fiber sheets were molded by a hot pressing method. In order to improve the adhesion at the matrix/fiber interface and to obtain uniformly dispersed bamboo fibers in PLA matrix, the bamboo fibers were treated by alkali solution. It was found that the composites reinforced by alkali-treated bamboo fibers have higher strength than those based on untreated ones. Bamboo fibers were uniformly dispersed in PLA matrix with improved interfacial adhesion as lignin in bamboo fibers were removed by the alkali treatment. It was concluded that alkali treatment was an effective method for improvement of interfacial matrix/fiber adhesion in PLA/bamboo fiber-reinforced green composites.

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Effect of Alkali Treatment on Structure and Properties of High Amylose Corn Starch Film

Materials ◽

10.3390/ma12101705 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1705 ◽

Cited By ~ 6

Author(s):

Yang Qin ◽

Hui Zhang ◽

Yangyong Dai ◽

Hanxue Hou ◽

Haizhou Dong

Keyword(s):

Tensile Strength ◽

Sodium Hydroxide ◽

Corn Starch ◽

Film Formation ◽

Alkali Treatment ◽

Hydroxyl Groups ◽

Elongation At Break ◽

Naoh Treatment ◽

High Amylose ◽

Starch Molecule

Alkali treatment is used for melt extrusion film formation with corn starch, but optimal conditions for this procedure are still unknown. In this study, the changes in properties and structure of high amylose corn starch (70%) films with different concentrations of sodium hydroxide (NaOH), prepared by melting extrusion, were investigated. With increasing sodium hydroxide concentrations, the tensile strength of the high-amylose starch film decreased gradually, while the elongation at break increased. The tensile strength of the high amylose starch (HAS) film with 2% NaOH-treatment was 10.03 MPa and its elongation at break was 40%. A 2% NaOH-treatment promoted the orderly rearrangement of starch molecules and formed an Eh-type crystal structure, which enlarged the spacing of the single helix structure, increased the molecular mobility of the starch, and slowed down the process of recrystallization; a 10% NaOH-treatment oxidized the hydroxyl groups of the high amylose corn starch during extrusion, formed a poly-carbonyl structure, and initiated the degradation and cross-linking of starch molecule chains.

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