Effects of Iron Oxide Content on the Growth of Silkworm and Properties of Silk

Silk fibers were produced by feeding Bombyx mori silkworm larvae with a modified feed of mulberry leaves containing nano Fe3O4 particles. The silkworms were weighed to determine the effect of nano Fe3O4 particles on the growth of larvae. The effects of nano Fe3O4 contents on the morphologies, chemical structures, mechanical properties, and thermal properties of silk were also investigated, respectively. The results indicate that the nano Fe3O4 particles was embedded in the silk. Additionally, the stress and toughness of modified silk were enhanced, as compared with the normal silk. Finally, the integration of the amide I band intensities suggests a relatively high content of β-sheet in the modified silk.