Some Mechanical Properties of Wool Fibers in the "Hookean" Region from Zero to 100% Relative Humidity

Feughelman, M.; Robinson, M. S.

doi:10.1177/004051757104100601

Cited by 64 publications

(27 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This indicated that the modified model for horns is a reasonable assumption. The hydration dependence is considered to be due to the water-matrix interaction, similar to that of wool which has been widely studied [17,105,111,122,164,192]. The explanations described previously (Section 2.4.4) can be applied to horns.…”

Section: Hornsmentioning

confidence: 99%

Keratin: Structure, mechanical properties, occurrence in biological organisms, and efforts at bioinspiration

Wang

Yang

McKittrick

et al. 2016

Progress in Materials Science

681

474

View full text Add to dashboard Cite

a b s t r a c tA ubiquitous biological material, keratin represents a group of insoluble, usually high-sulfur content and filament-forming proteins, constituting the bulk of epidermal appendages such as hair, nails, claws, turtle scutes, horns, whale baleen, beaks, and feathers. These keratinous materials are formed by cells filled with keratin and are considered 'dead tissues'. Nevertheless, they are among the toughest biological materials, serving as a wide variety of interesting functions, e.g. scales to armor body, horns to combat aggressors, hagfish slime as defense against predators, nails and claws to increase prehension, hair and fur to protect against the environment. The vivid inspiring examples can offer useful solutions to design new structural and functional materials.Keratins can be classified as a-and b-types. Both show a characteristic filament-matrix structure: 7 nm diameter intermediate filaments for a-keratin, and 3 nm diameter filaments for b-keratin.Both are embedded in an amorphous keratin matrix. The molecular unit of intermediate filaments is a coiled-coil heterodimer and that of b-keratin filament is a pleated sheet. The mechanical response of a-keratin has been extensively studied and shows linear Hookean, yield and post-yield regions, and in some cases, a high reversible elastic deformation. Thus, they can be also be considered 'biopolymers'. On the other hand, b-keratin has not been investigated as comprehensively. Keratinous materials are strain-rate sensitive, and the effect of hydration is significant.Keratinous materials exhibit a complex hierarchical structure: polypeptide chains and filament-matrix structures at the nanoscale, Progress in Materials Science 76 (2016) 229-318 Contents lists available at ScienceDirect Progress in Materials Sciencej o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / p m a t s c i organization of keratinized cells into lamellar, tubular-intertubular, fiber or layered structures at the microscale, and solid, compact sheaths over porous core, sandwich or threads at the macroscale. These produce a wide range of mechanical properties: the Young's modulus ranges from 10 MPa in stratum corneum to about 2.5 GPa in feathers, and the tensile strength varies from 2 MPa in stratum corneum to 530 MPa in dry hagfish slime threads. Therefore, they are able to serve various functions including diffusion barrier, buffering external attack, energy-absorption, impact-resistance, piercing opponents, withstanding repeated stress and aerodynamic forces, and resisting buckling and penetration.A fascinating part of the new frontier of materials study is the development of bioinspired materials and designs. A comprehensive understanding of the biochemistry, structure and mechanical properties of keratins and keratinous materials is of great importance for keratin-based bioinspired materials and designs. Current bioinspired efforts including the manufacturing of quill-inspired aluminum composites, animal horn-inspired SiC composites, and feather-i...

show abstract

Section: Hornsmentioning

confidence: 99%

Keratin: Structure, mechanical properties, occurrence in biological organisms, and efforts at bioinspiration

Wang

Yang

McKittrick

et al. 2016

Progress in Materials Science

681

474

View full text Add to dashboard Cite

show abstract

“…The mechanical properties of keratinous biomaterials in a broad array of taxa have been examined. Some relevant experimental results on the elastic moduli with hydration effect are summarized in Table1, including those of hagfish thread (Fudge and Gosline, 2004), horse hoof (Bertram and Gosline, 1987;Douglas et al, 1996), donkey hoof (Collins et al, 1998), bovid hoof (Franck et al, 2006;Zhang et al, 2007), ostrich claw and feather (Bonser, 2000;Taylor et al, 2004), swan feather and goose feather (Cameron et al, 2003), human hair and nail (Baden, 1970;Wei et al, 2005), wool (Feughelman and Robinson, 1971), as well as antelope horn sheath (Kitchener and Vincent, 1987).…”

Section: Introductionmentioning

confidence: 99%

Experimental study on the mechanical properties of the horn sheaths from cattle

Zhao

Feng

et al. 2010

Journal of Experimental Biology

View full text Add to dashboard Cite

SUMMARYBovine horn is composed of a sheath of keratin overlying a bony core. Previous studies of the bovine horn sheath have focused mainly on its morphology and compositions. In the present paper, we performed a series of uniaxial tension, three-point bending, and fracture tests to investigate the structural and mechanical properties of the horn sheaths from subadult cattle, Bos taurus. The effects of hydration on the mechanical properties were examined and their variations along the longitudinal direction of the horn sheath were addressed. Scanning electron microscopy of the fracture surfaces showed that the horn sheath has a layered structure and, more interestingly, the laminae have a rippled appearance. The Young's modulus and tensile strength increase from 850MPa and 40MPa at 19% water content to 2.3GPa and 154MPa at 0% water content, respectively. The Poisson's ratio of the horn sheath was about 0.38. The critical stress intensity factor was about 4.76MPam 1/2 at an intermediate hydration (8% water content), greater than that at 0% water content (3.86MPam 1/2 ) and 19% water content (2.56MPam 1/2 ). The bending properties of the samples varied along the length of the horn. The mean flexural moduli of the specimens in the distal, middle and proximal parts were about 6.26GPa, 5.93GPa and 4.98GPa, respectively; whereas the mean yield strength in the distal segment was about 152.4MPa, distinctly higher than that in the middle (135.7MPa) and proximal parts (116.4MPa). This study deepens our understanding of the relationships among optimal structure, property and function of cattle horn sheaths.

show abstract

“…While the apparent modulus of the fiber in the preyield region is both time-and water-dependent, the equilibrium modulus (1.4 GPa) is independent of water content and corresponds to the modulus of the crystalline phase (76). The time-, temperature-, and water-dependence can be attributed to the viscoelastic properties of the matrix phase.…”

Section: Tensile Propertiesmentioning

confidence: 99%

Wool: Structure, Properties, and Processing

Rippon

Christoe

Denning

et al. 2016

Encyclopedia of Polymer Science and Technology

View full text Add to dashboard Cite

Wool, the fibrous coating from sheep, is the most important animal fiber used by the textile industry. It has been used continuously for several thousand years, the earliest type of fabric made from wool probably being a felt. Although the relative importance of wool as a textile fiber has declined with the increasing use of synthetic fibers, it remains important in some sectors of the market. This article discusses raw wool specification, fiber growth, its complex morphological and chemical structure, and the physical properties that make wool unique among textile fibers. Also discussed are the processing steps used to transform raw wool into consumer products, namely, scouring, carbonizing, carding, spinning, setting, dyeing, bleaching, printing, and treatments to reduce felting shrinkage, insect damage, and flammability. A novel textile fiber made from wool (Optim TM , CSIRO) is also described.

show abstract

Some Mechanical Properties of Wool Fibers in the "Hookean" Region from Zero to 100% Relative Humidity

Cited by 64 publications

References 12 publications

Keratin: Structure, mechanical properties, occurrence in biological organisms, and efforts at bioinspiration

Keratin: Structure, mechanical properties, occurrence in biological organisms, and efforts at bioinspiration

Experimental study on the mechanical properties of the horn sheaths from cattle

Wool: Structure, Properties, and Processing

Contact Info

Product

Resources

About