Study on porous silk fibroin materials. II. Preparation and characteristics of spongy silk fibroin materials

Porous silk fibroin materials, with average pore size 10 similar to 300 mum , pore density 1 similar to 2000/mm(2), and porosity 35 similar to 70%, wer e prepared by freeze drying aqueous solution of silk fibroin obtained by di ssolving silk fibroin in ternary solvent CaCl2 . CH3CH2OH . H2O. Pore size distribution of such materials mostly accorded with logarithmic normal dist ribution. It is possible to control the aforementioned structural parameter s and the physical properties of moisture permeability, compressibility, st rength, elongation, etc., by adjusting freezing temperature and concentrati on of silk fibroin solution. Above glass transition zone (-34 similar to -2 0 degreesC) of silk fibroin, the freezing temperature has more significant effect on the structure and properties of porous silk fibroin materials. (C ) 2001 John Wiley & Sons, Inc.