Structure and properties of silk fibers produced by Antheraea polyphemus

This paper reports the structure and properties of silk fibers produced by Antheraea polyphemus. Silk fibers produced by Antheraea polyphemus had tensile properties very similar to that of B. mori silk and much better than the properties of the wild silks in current use. Saturniidae insects are relatively easy to rear and produce larger cocoons than B. mori caterpillars. However, common saturniidae insects such as Antheraea mylitta, Antheraea pernyi and Phylisomia ricini that are reared to produce silk (wild silk) for commercial applications have properties inferior to that of B. mori silk. A. polyphemus also belongs to the saturniidae family of cocoon producing insects but the structure and properties of polyphemus silks have not been reported. In this research, we have studied the structure and properties of silk fibers produced by A. polyphemus in comparison to B. mori and the common wild silks.lt was found that A. polyphemus silk has different amino acid composition than B. mori and wild silks. However, polyphemus silk fibers had an average breaking tenacity of 4.8 g/den, breaking elongation of 15% and Young's modulus of 87 g/den, very similar to that of B. mori silk. Morphologically, the fibers were considerably flat and ribbon-like with solid cross-sections. Overall, polyphemus silk fibers had structure and properties suitable for applications that use B. mori and the common wild silks.