Biopolymer Electrolytes

Fundamentals and Applications in Energy Storage

Sudhakar Y N, M. Selvakumar, D. Krishna Bhat, Sudhakar Y.N.

• Publisher: Elsevier
• Year: 2018
• Print ISBN: 9780128134474
• eBook ISBN: 9780128136119
• Topic: Physical Sciences
• Subtopic: Physical & Theoretical Chemistry

Biopolymer Electrolytes: Fundamentals and Applications in Energy Storage provides the core fundamentals and applications for polyelectrolytes and their properties with a focus on biopolymer electrolytes. Increasing global energy and environmental challenges demand clean and sustainable energy sources to support the modern society. One of the feasible technologies is to use green energy and green materials in devices. Biopolymer electrolytes are one such green material and, hence, have enormous application potential in devices such as electrochemical cells and fuel cells.- Features a stable of case studies throughout the book that underscore key concepts and applications- Provides the core fundamentals and applications for polyelectrolytes and their properties- Weaves the subject of biopolymer electrolytes across a broad range of disciplines, including chemistry, chemical engineering, materials science, environmental science, and pharmaceutical science

Chapter 1

An introduction of Biopolymer Electrolytes

Abstract

This chapter gives a general introduction to the subject of biopolymers and biopolymer electrolytes along with their classification. The varieties of biopolymers and biopolymer electrolytes and role of different dopants in biopolymer electrolytes are presented. A brief account of the polymer dissolution in solvent as well as solvent-solute, polymer-solute interaction is included in this chapter. Description of polymer miscibility in the case of blend biopolymer electrolytes is given based on the viscosity of polymer solutions. In the case of gel polymer electrolytes, the formation of sol-gel is explained based on crosslinking and hydrogen bonding. Also, the solvent-solute interaction in solid polymer electrolyte is explained based on interaction parameters. The formation of hydrogel and composite biopolymer electrolyte is narrated in this chapter. The improvement of conductivity among the polymer electrolytes is explained based on the fundamental mechanism. A discussion on the properties, advantages, and disadvantage of each polymer electrolytes is provided at the end of this chapter.

Keywords

Biodegradable; Biopolymers; Compostable; Environmental; Dopants; Sustainable

Chapter Outline

• 1.1 Biodegradable Polymers/Biopolymers
  • 1.1.1 Common Biopolymers
  • 1.1.2 Opportunity
• 1.2 Polymer Electrolytes
• 1.3 Biopolymer Electrolytes
• 1.4 Classification of Biopolymer Electrolytes
• 1.5 Dopants
  • 1.5.1 Lithium Salts as Dopants in Biopolymer Electrolytes
  • 1.5.2 Acids as Dopants in Biopolymer Electrolytes
  • 1.5.3 Alkaline Dopants in Polymer Electrolytes
  • 1.5.4 Plasticizing Salts/Ionic Liquids
• 1.6 Solid Biopolymer Electrolytes (SBPE)
  • 1.6.1 Polymer Dissolution
  • 1.6.2 Movements of Ions in SPE
  • 1.6.3 Proton Conduction Mechanisms
  • 1.6.4 Dependence of Cation Mobility on the Relative Molar Mass of the Polymer Host
• 1.7 Blend Biopolymer Electrolytes (BBPE)
  • 1.7.1 Introduction of BBPE
  • 1.7.2 Miscibility and Thermodynamic Relationships of Biopolymer Blends
  • 1.7.3 Interaction Parameter (χ)
• 1.8 Gel Biopolymer Electrolytes (GBPE)
  • 1.8.1 Introduction of GBPE
  • 1.8.2 Sol-Gel (Gelation)
  • 1.8.3 Conductivity
• 1.9 Hydrogel Biopolymer Electrolytes (HBPE)
  • 1.9.1 Introduction of HBPE
  • 1.9.2 Mechanism for the Formation of Hydrogel
• 1.10 Composite Biopolymer Electrolytes (CBPE)
• 1.11 Comparison of Solid, Blend, and Gel Biopolymer Electrolytes
  • 1.11.1 Solid Biopolymer Electrolyte
  • 1.11.2 Blend Biopolymer Electrolytes
  • 1.11.3 Gel Biopolymer Electrolytes
• References

1.1 Biodegradable Polymers/Biopolymers

Biodegradable polymers/biopolymers are emerging as one of the hottest fields for addressing current environmental issues toward a sustainable future. This desire has made scientists explore natural polymers and mimic them with various combinations to synthesize them with better properties. They have also identified a few microorganisms and enzymes capable of degrading biopolymers. Explosive population growth has raised concerns in several parts of the world regarding issues such as deficiencies in food, resources, and energy as well as global environmental pollution. Science has to lead the world in a more mutual beneficial development by utilizing the lands in underdeveloped countries for growing the resources needed for biodegradable polymers. Dependence on synthetic polymers must decline because some countries are restricting the use of nonbiodegradable polymers. Synthetic polymers as of now are difficult to completely remove from the marketplace and may be produced until the fossil resources are available. Recycling of plastics is promoted more intensively nowadays, but recycling alone will not solve plastic pollution. Recycling requires considerable amounts of energy and eventually nonrecyclable plastics are incinerated or buried in landfills. Taking this into consideration, the importance and necessity of biodegradable polymers can be easily estimated [1,2]. The biodegradability of a polymer mainly depends on the chemical structure and products formed after biodegradation. Therefore, biopolymers are based on natural or synthetic materials.

Natural biopolymers are based mainly on renewable resources. Synthetic biopolymers usually are petroleum-based. To meet the functional requirements in the marketplace, many natural biopolymers are blended with synthetic polymers to get blended biopolymers. Having synthetic parts in the polymer chain makes the claim of biodegradability partially agreeable, as these are, in fact, bioerodable, photobiodegradable, or hydrobiodegradable. Along with microorganisms, environmental factors have an influence on the degradability of biopolymers. Nevertheless, biopolymers may be categorized based on their degradability in the environment under such terms as biodegradable, compostable, photobiodegradable, hydrobiodegradable, and bioerodable.

(a) Biodegradable

There are various definitions for biodegradation. One of them, according to ASTM, the biodegradable is defined as, “Capable of undergoing decomposition into carbon dioxide, methane, water, inorganic compounds, or biomass in which the predominant mechanism is the enzymatic action of microorganisms that can be measured by standardized tests, in a specified period of time reflecting available disposal conditions.”

Biopolymers should be enzymatically broken down by microorganisms in a defined time into molecules such as carbon dioxide and water. The...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Chapter 1: An introduction of Biopolymer Electrolytes
• Chapter 2: Methods of Preparation of Biopolymer Electrolytes
• Chapter 3: Biopolymer Electrolyte for Supercapacitor
• Chapter 4: Biopolymer Electrolytes for Solar Cells and Electrochemical Cells
• Chapter 5: Biopolymer Electrolytes for Fuel Cell Applications
• Chapter 6: Biopolymer Degradation
• Index