Abstract
The aqueous solution of silk fibroin, prepared by the cupriethylenediamine method, was hydrolyzed by trypsin and chymotrypsin, then crystalline materials was deposited. The crystals from trypic proteolysis precipitate (FTP) and chymotrypic proteolysis precipitate (FCP) were found to be β-structure. The β-structure of FCP was changed to α-structure (FCPIX) in the recrystallization at room temperature in water. Crystals-blended materials of various composition were prerared by dissolving in 3/4 cupriethylenediamine and dialyzed. The blended white precipitates were obtained from the dialyzing tube and drops containing blended precipitates in suspension were dried by covering with thin film of cupper screen.
In this procedure, presence of β-structure was confirmed in their mixture if FTP (β-form) is contained more than 2% in the mixture of FTP and FCP1X. On the electron microscopic observations. α-form shows linear sheaf-like fibrillar crystals, but according to increase of FTP contents, crystals obtained from the mixture of FTP and FCP 1X are twisted and become short. Finally, the crystals approach at globular β-structure.
In the differential thermal analysis, when blends contain 5_??_10% FTP, the degradation of temperature were 324_??_326°C and thermal energy of degradation required to break down intermolecular bonds was greater than FTP and FCP 1X. Moreover, posture of crystals-blends of FTP and FCP 1X are discused briefly.
