抄録
To clarify the physical properties of silk yarns, cocoons and yarns of 12 different silk species were analyzed by solid-state 13CNMR and their amino acid compositions and spin-lattice relaxation time (T1) were compared. The correlation between these values and physical values of yarns obtained by tensile strength measurements were discussed. Mole fraction of glycine (glycine⁄(glycine+alanine+serine+valine)) and T1 of cocoons and yarns were different depending on the silk species. These values of cocoons in Japanese species scattered over a wide range and showed high correlation between them. On the other hand those of the Chinese species are in a narrow range , and T1’s are smaller than Japanese ones. Among them Shisensanmin, Kankokakuken and Ikoken showed extremely large mole fractions of glycine and small T1, meaning that these three species have excellent rigid but soft physical property. Mole fraction of glycine and T1’s of most of the Japanese species in yarns became larger than those of cocoons. Japanese species increased their flexibility by reeling, but Chinese and European species decreased it. Among them Matamukashi, Onichijira and Kankokakuken showed excellent rigid but soft physical property in yarns. Mole fraction of glycine showed high correlation with viscosity and T1 showed high correlation with Young’s modulus. In these correlations there are differences between Japanese and Chinese species.
