Natural Fiber-Reinforced Biodegradable and Bioresorbable Polymer Composites

Alan Kin-tak Lau, Ada Pui Yan Hung

• Publisher: Woodhead Publishing
• Year: 2017
• Print ISBN: 9780081006566
• eBook ISBN: 9780081006696
• Topic: Technology & Engineering
• Subtopic: Materials Science
• Index: Technology & Engineering

Natural Fiber-Reinforced Biodegradable and Bioresorbable Polymer Composites focuses on key areas of fundamental research and applications of biocomposites. Several key elements that affect the usage of these composites in real-life applications are discussed. There will be a comprehensive review on the different kinds of biocomposites at the beginning of the book, then the different types of natural fibers, bio-polymers, and green nanoparticle biocomposites are discussed as well as their potential for future development and use in engineering biomedical and domestic products.Recently mankind has realized that unless the environment is protected, he himself will be threatened by the over consumption of natural resources as well as a substantial reduction in the amount of fresh air produced in the world. Conservation of forests and the optimal utilization of agricultural and other renewable resources like solar, wind, and tidal energy, have become important topics worldwide. With such concern, the use of renewable resources—such as plant and animal-based, fiber-reinforced polymeric composites—are now becoming an important design criterion for designing and manufacturing components for a broad range of different industrial products.Research on biodegradable polymeric composites can contribute, to some extent, to a much greener and safer environment. For example, in the biomedical and bioengineering fields, the use of natural fiber mixed with biodegradable and bioresorbable polymers can produce joint and bone fixtures to alleviate pain in patients.- Includes comprehensive information about the sources, properties, and biodegradability of natural fibers- Discusses failure mechanisms and modeling of natural fibers composites- Analyzes the effectiveness of using natural materials for enhancing mechanical, thermal, and biodegradable properties

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Natural fiber-reinforced polymer-based composites

Alan Kin-tak Lau¹ and Karen Hoi Yan Cheung², ¹Swinburne University of Technology, Hawthorn, Melbourne, VIC, Australia, ²Hong Kong Green Building Council, Kowloon, Hong Kong, SAR China

Abstract

Recently, the mankind has realized that unless environment is protected, he himself will be threatened by the over consumption of natural resource as well as substantial reduction of fresh air produced in the world. Conservation of forests and optimal utilization of agricultural and other renewable resources like solar and wind energies, and recently, tidal energy have become important topics worldwide. In such concern, the use of renewable resources such as plant and animal based fiber-reinforced polymeric composites, has been becoming an important design criterion for designing and manufacturing components for all industrial products. Research on biodegradable polymeric composites can contribute to green and safe environment to some extent. In the biomedical and bioengineered field, the use of natural fiber mixed with biodegradable and bioresorbable polymers can produce joints and bone fixtures to alleviate pain for patients. In this chapter, a comprehensive review on different kinds of natural fiber composites will be given. Their potential in future development of different kinds of engineering and domestic products will also be discussed in detail.

Keywords

Biocomposites; natural fiber; animal fiber; environmentally friendly

1.1 Introduction

Over the past few decades, research and engineering interest has been shifting from traditional monolithic materials to fiber-reinforced polymer-based composites due to their unique advantages of high strength to weight ratio, noncorrosive property, and high fracture toughness. These composite materials consisting of high strength fibers, such as carbon, glass, and aramid, and low strength polymeric matrix, have now dominated the aerospace, leisure, automotive, construction and sporting industries. Unfortunately, these fibers have serious drawbacks such as (1) nonrenewable; (2) nonrecyclable; (3) high energy consumption in the manufacturing process; (4) health risk when inhaled; and (5) nonbiodegradable. Biodegradation is the chemical breakdown of materials by the action of living organisms which leads to a change in physical, mechanical, and chemical properties. It is a concept of vast scope, ranging from the decomposition of environmental wastes involving microorganisms to host-induced biomaterials.

Although glass fiber-reinforced polymer composites have been widely used due to their advantages of low cost and moderate strength for many years to provide solutions to many structural problems, the use of these materials, in turn would induce a serious environmental problem that is now of concern in most Western countries. Recently, due to a strong emphasis on environmental awareness worldwide, it has brought much attention in the development of recyclable and environmentally sustainable composite materials. Environmental legislation as well as consumer demand in many countries are increasing the pressure on manufacturers of materials and end-products to consider the environmental impact at all stages of their life cycle, including recycling and ultimate disposal. In the United State, it encourages manufacturers to produce materials and products by practicing the 4Rs, which are (1) Reduce the amount and toxicity of trash to be discard (sourced reduction); (2) Reuse containers and products; (3) Repair what is broken; and (4) Recycle as much as possible, which includes buying products with recycled content. After these processes are gone, the materials finally are entitled to be disposed into landfill.

The most common types of conventional composites are usually composed of epoxy, unsaturated polyester resin, polyurethanes, or phenolic reinforced by glass, carbon, or aramid fibers. These composite structures lead to the problem of conventional removal after the end of their life time, as the components are closely interconnected, relatively stable, and thus difficult to be separated and recycled. The recent development of aircraft, such as Boeing 787 and AIRBUS 350, use over 50% of composites as their structural components. A serious problem that brings a strong debate is on the recyclability of the composites after the end of their service life. During the production process, the use of energy to make fibers and resins is another arguable item. However, the advantage of using these materials is due to their light-in-weight, noncorrosive properties, and the ease of manufacturing in different forms and shapes without involving the use of heavy equipment. Therefore, if the natural fiber and biodegradable matrix are used for a new type of biocomposite and can achieve similar functions and strength as glass fiber-reinforced polymer (GFRP) composites, it would help solve many environmental problems addressed above and help improve the living environment in our planet.

Within the past few years, there has been a dramatic increase in the use of natural fibers, such as leaves from flax, jute, hemp, pineapple, and sisal, for making a new type of environmentally-friendly composite. Recent advances in natural fiber development, genetic engineering, and composite science offer significant opportunities for improved materials from renewable resources with enhanced support for global sustainability. In general, two types of natural fibers are identified for making fiber-reinforced polymer; they are (1) plant-based fibers and (2) animal-based Fibers. For the former, due to their abundant supply in the natural environment, the raw material cost is relatively low and can compete with synthetic fibers, such as glass to make the composites. Animal fibers, however, are difficult to collect from wildlife and, normally, have to be obtained from home-fed animals, such as spiders and cocoons.

By using the plant-based natural fiber as reinforcement of polymer-based materials the reduction of the use of synthetic fibers and undegradable polymer for composite structures can be targeted. Excessive use of petroleum-based plastics induces huge amounts of nondecomposable solid waste which causes a serious depletion of landfill capacities. The awareness of the soaring waste problems on the environment has awakened a new interest in the area of materials science and engineering. Because of the increasing environmental consciousness in the society, it is a critical topic for researchers to study different alternatives to replace nonrenewable materials, especially for petroleum-based plastics. Therefore, different types of fully biodegradable materials have been developed recently, as substitutions for nonbiodegradable petroleum-based plastics, and even metallic components [1–4].

Among all the natural fibers, sisal [5], hemp [5], basalt [6], kenaf [7], flax [8], and bamboo fibers [9] are the most common types to be used due to...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of Contributors
• Preface
• 1. Natural fiber-reinforced polymer-based composites
• 2. Particleboards from agricultural lignocellulosics and biodegradable polymers prepared with raw materials from natural resources
• 3. Green composites made from cellulose nanofibers and bio-based epoxy: Processing, performance, and applications
• 4. Biodegradable fiber-reinforced polymer composites for construction applications
• 5. Bleached kraft softwood fibers reinforced polylactic acid composites, tensile and flexural strengths
• 6. Silk for sustainable composites
• 7. Effects of cellulose nanowhiskers preparation methods on the properties of hybrid montmorillonite/cellulose nanowhiskers reinforced polylactic acid nanocomposites
• 8. Bio-based resins for fiber-reinforced polymer composites
• 9. Processing of lignocellulosic fiber-reinforced biodegradable composites
• Index