A STUDY OF THE MECHANICAL BEHAVIOR OF SPIDER SILKS
Final rept. Apr 1967-Apr 1968
COLLABORATIVE RESEARCH INC WALTHAM MA
Pagination or Media Count:
A preliminary physical and chemical examination of a selected group of spider silks was made. The programs ultimate goal was the synthesis of super tenacity protein fibers, and the work reported here was designed to confirm the existence of very strong, natural protein fibers, specifically, spider silks determine some of the physical properties of such fibers and obtain information on the chemical make-up of strong protein fibers and compare them with weaker protein fibers. During this study, collection techniques were streamlined and large quantities of spider silk were obtained. It was shown that a variety of these spider silks have average rupture tenacities exceeding 10 gms per denier and that a few show tenacities exceeding 15 gms per denier. These strengths class these fibers among the strongest organic fiber known. Equally remarkable, however, are the elongations before rupture - amounting to 15 percent or more. Fractionation studies on spider silk indicate that it is almost completely of the fibrous form with little or no soluble globular components. Amino acid assays show that the silk contains primarily the simpler amino acids and has a possible relation to a collagen structure.