Structure and properties of Camphor silk

Wild non-mulberry silk has long been mainly used as a textile fiber and as biomedical sutures for decades. In this study, we reported a unique wild silk variety, the Camphor silk. Compared with the Bombyx mori (B. mori) silk and Antheraea pernyi (A. pernyi) silk cocoons, the Camphor silkworm cocoon is smaller and has a thinner cocoon wall. Similar to the A. pernyi cocoon, the Camphor cocoon also has a large amount of crystals covering its outer layers. The breaking strength and tenacity of the Camphor silk with and without degumming were significantly higher than that of A. pernyi and B. mori silks. Moreover, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermo gravimetric (TG) analyses were employed to provide an insight into the superior mechanical properties of the Camphor silk. The results showed that the Camphor silk has a high degree of crystallinity and high decomposition temperature (329 °C), which contribute to its outstanding mechanical properties. This study provides a new alternative protein material for composites and biomedical devices.