Physicochemical Properties of Spider Silk—An Approach to Nanostructure

Many properties of spider silks have been studied including the physicochem-istry, mechanical stress, elastic modulus and strain energy.The present author has investigated the thermal, optical, molecular, aging and mechanical properties of spider silks. 

It is meaningful to study the thermal properties of spider s silk thread from the heat resistant point of view since spider silks adhere to some objects such as rock and metal and may be heat-stable even at high temperatures between 60 °C and 100 °C. However, the thermal properties have not previously been studied, probably due to the difficulty in collecting draglines. Spider threads have been studied mainly from the morphological point of view.  

The orb-web is irradiated outdoors by ultraviolet (UV) rays. It is interesting to ask from the aging point of view how UV-irradiation affects spider silks at different stages of life and to study the effects of UV-irradiation. However, there have been no reports on the effects of UV rays upon draglines. 

It is uncertain whether spider silks show actual characteristic properties even though many researchers have been interested in the physicochemical properties of spider silks.This is mainly due to the difficulty in obtaining sufficient numbers of dragline samples appropriate for thermal, optical and aging experiments, in preparing the samples with no mechanical hysteresis and in measuring the mechanical properties because the silk samples are very thin. 

Recently, the author overcame such difficulties and was able to measure the physical properties of spider silks. As a result new information was obtained from the measurements of spider silks. An approach to the mass production of spider silks actually became meaningful due to the development of genetic technolo-gy 134-136) important to study the characteristics of the physicochemical 

---

Physicochemical Properties of Spider Silk-An Approach to Nanostructure... 

---