Natural Fibre Composites

Materials, Processes and Properties

Alma THULE, Robert Shanks, Alma Hodzic

• Publisher: Woodhead Publishing
• Year: 2014
• Print ISBN:
  9780857095244
• eBook ISBN:
  9780857099228
• Topic: Tecnologia e ingegneria
• Subtopic: Scienza dei materiali

The use of natural fibres as reinforcements in composites has grown in importance in recent years. Natural Fibre Composites summarises the wealth of significant recent research in this area. Chapters in part one introduce and explore the structure, properties, processing, and applications of natural fibre reinforcements, including those made from wood and cellulosic fibres. Part two describes and illustrates the processing of natural fibre composites. Chapters discuss ethical practices in the processing of green composites, manufacturing methods and compression and injection molding techniques for natural fibre composites, and thermoset matrix natural fibre-reinforced composites. Part three highlights and interprets the testing and properties of natural fibre composites including, non-destructive and high strain rate testing. The performance of natural fibre composites is examined under dynamic loading, the response of natural fibre composites to impact damage is appraised, and the response of natural fibre composites in a marine environment is assessed. Natural Fibre Composites is a technical guide for professionals requiring an understanding of natural fibre composite materials. It offers reviews, applications and evaluations of the subject for researchers and engineers. - Introduces and explores the structure, properties, processing, and applications of natural fibre reinforcements, including those made from wood and cellulosic fibres - Highlights and interprets the testing and properties of natural fibre composites, including non-destructive and high strain rate testing - Examines performance of natural fibre composites under dynamic loading, the response of natural fibre composites to impact damage, and the response of natural fibre composites in a marine environment

Part I

Natural fibre reinforcements

Outline

Chapter 1: Wood fibres as reinforcements in natural fibre composites: structure, properties, processing and applications

Chapter 2: Chemistry and structure of cellulosic fibres as reinforcements in natural fibre composites

Chapter 3: Creating hierarchical structures in cellulosic fibre reinforced polymer composites for advanced performance

Chapter 4: Recycled polymers in natural fibre-reinforced polymer composites

Chapter 5: Electrospun cellulosic fibre-reinforced composite materials

1

Wood fibres as reinforcements in natural fibre composites: structure, properties, processing and applications

D. Dai and M. Fan, Brunel University, UK

Abstract:

Wood fibres are the most abundantly used cellulose fibre. They have been extensively used in the modern composite industry due to their specific characteristics. This chapter systematically describes the structure, properties, processing and applications of wood fibres as reinforcements in natural fibre composites: first, the nature and behaviour of wood fibres and the developed technologies for the modification of wood fibres to enhance physical and mechanical properties (e.g. surface functionality and tensile strength) are investigated; the matrices and processing techniques for the development of wood fibre composites are then discussed; and finally, the properties and applications of wood fibre composites in industrial sectors are presented.

Key words

wood fibres

structure

physical and mechanical properties

modification

process technique

wood fibre composites

1.1 Introduction

Natural fibres are rich in cellulose, abundantly available and easy to handle and process. However, the application of natural fibres in composites came to a near-halt from the 1940s due to the low price and the steadily rising performance of technical and standard plastics.^{1, 2} In the 1990s, critical discussion about the preservation of natural resources and recycling had led to a renewed interest in natural renewable materials. With the recent increase in environmental awareness, exploiting natural fibres has raised great interest and become of importance. Among these natural fibres, wood fibres are the most abundantly used cellulose fibre having extensive use in the fibreboard, pulp and paper, and many other industrial sectors. Over 55% of paper and paperboard production³ and 80% of natural fibre reinforced composites⁴ are made from wood fibres. The use of wood composite materials dates from centuries ago.⁵ In ancient China, wood, bamboo and straw were used to reinforce clay for making walls, and clay for making walls, and many natural fibre-reinforced clay buildings are still in use, e.g. the ‘Tulou’, which dates from 1200 years ago, one of the oldest wood-clay buildings, can be observed in the south of China (Fig. 1.1).

1.1 Yuchang Lou in Fujian, China: a wood–clay composite building that is over 600 years old.

To date, numerous publications have reported the applications of natural fibres, e.g. pulp,^{6, 7} ethanol⁸ and composite.⁹ Among these reports, more than 85% focus on wood fibres. In addition, the growing importance of wood fibres can be evidenced from the increasing number of publications in the past 10 years (Fig. 1.2). It should be noted that these publications derive from the Google scholar database with the key word of wood fibre, and it is found that more than 75% of the publications are from journals or conferences, and about 70% of these reports focus on wood fibre composites.

1.2 Number of publications on wood fibres and products.

The development of nanotechnology (NT) and biotechnology in the past 10 years has pushed the research and development of wood fibres a step further, and enlarged the role of wood fibres in many industrial sectors, such as pulp and paper, and material industries.

1.2 Wood fibres: nature and behaviour

1.2.1 Structure of wood fibres

Wood fibres consist of both live and dead cells in the wood, depending on the location and the age of tree from which they are extracted. The hierarchical structure of wood fibres gives this fibrous material excellent performance properties, e.g. high strength to weight ratio. Wood fibres can be obtained from timber by chemical, mechanical, biological processes, and many combined processes.

At the macroscopic level (normally 0.1–1 m), wood fibres mainly exist within the layer of xylem in the wood¹⁰ (Fig. 1.3(1)). The dark strip in the centre of the stem is the pith, which represents the tissues formed during th...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Contributor contact details
• Woodhead Publishing Series in Composites Science and Engineering
• Part I: Natural fibre reinforcements
• Part II: Processing of natural fibre composites
• Part III: Testing and properties
• Index