Egg Case Spider Silk Properties

Silk fibers extracted from egg case of spider collected in Saveh (Iran) region examined by an optical polarizing microscope, FTIR spectroscopy , differential scanning calorimeter, interference microscope and tensile mechanical tester. The fiber diameters are in the range of 5 ±1μm.The main FTIR bands observed in silk and draglines are also found in egg cease fibers but their absorption intensities are different. The fibers are bireferingent (ΔN= 0.013-0.016). There thermal properties are similar to silk, two endothermic peaks at 75 ºC and 315ºC and a shoulder at 220ºC. Fiber tensile strength amounts 0.86 GPa that is in order of the strength of spider drag line.

Keywords:

spider silk , protein , egg case , properties