Page 78 - Handbook of Properties of Textile and Technical Fibres

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3
Properties of wool

Michael G. Huson
Commonwealth Scientiﬁc and Industrial Research Organisation (CSIRO), Geelong, VIC,
Australia

3.1 Introduction

Wool is a complex biocomposite, typically 16e30 mm in diameter with an outer
covering of overlapping cuticle cells, which forms a protective sheath and also confers
on wool its ability to felt. A scanning electron micrograph of a clean Merino wool ﬁber
is shown in Fig. 3.1. Wool has been used as a textile ﬁber since before the beginning of
recorded history, the earliest type of fabric made from wool probably being a felt. It has
been the subject of serious research for the last 90 years, with researchers from around
the world meeting every 5 years at an International Wool Textile Research Confer-
ence. Early work focused on trying to understand the basic chemistry and physics
of the ﬁber with structureeproperty relationships and the chemical nature of the sur-
face becoming more important with time. There has always been strong interest in the
tensile properties of wool, with a recognition that weak ﬁbers break during processing,
decreasing ﬁber length in the top and increasing losses during processing. A lot of
effort has gone into trying to understand the stressestrain properties of a-keratin ﬁ-
bers, including wool, with the major focus being the nonfailure properties such as
modulus, yield stress, and postyield slope. This work has been well documented by
Feughelman (1982, 1997, 2002), Hearle (2000, 2002, 2003, 2007), and Chapman

Figure 3.1 Scanning electron
micrograph of a Merino ﬁber,
showing overlapping cuticle
cells.
Image courtesy: CSIRO Science
Images (http://www.
scienceimage.csiro.au).

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