Page 339 - Fiber Fracture

FRACTURE OF NATURAL POLYMERIC FIBRES 321

Body wall (dermis)

Sea cucumber

v?4 L/ /// / Ball-and-socket joint

Fig. 7. Sections of sea cucumber and sea urchin, respectively showing the location of the body wall and the
‘catch’ ligament in these animals. For clarity, the sea urchin is drawn with spines on the right and tube feet
on the left; in reality, these structures are intermixed over the whole surface. (After Hyman, 1955; Banister
and Campbell, 1985; Pearse et al., 1987; Lambert, 1997.)

that this shape reduces the volume of fibre that is not exploited at close-to-maximum
load-bearing capacity. Therefore, supramolecular self-assembly in this instance has the
further advantage of ensuring that the tensile strength of the fibre is exploited efficiently.