Mechanical properties of silk fibroin-microcrystalline cellulose composite films

作者：Noishiki Y^*; Nishiyama Y; Wada M; Kuga S; Magoshi J

来源：Journal of Applied Polymer Science, 2002, 86(13): 3425-3429.

DOI：10.1002/app.11370

• nanocomposites
• crystal structures
• biopolymers
• mechanical properties
• thin films

Silk fibroin-microcrystalline cellulose (cellulose whisker) composite films with varied compositions were prepared by casting mixed aqueous solution/suspensions of the two components. Silk fibroin was dissolved in 10M LiSCN followed by dialysis; a cellulose whisker suspension was prepared by sulfuric acid hydrolysis of tunicate cellulose. Macroscopically homogeneous films were obtained at all mixing ratios. While the Young's modulus of the composite films showed a linear, additive dependence on the mixing ratio, the tensile strength and ultimate strain showed a maximum at a 70-80% cellulose content, reaching five times those of fibroin-alone or cellulose-alone films. At the same mixing ratio, infrared spectra of the composite films showed a shift of the amide I peak from 1654 to 1625 cm(-1), indicating the conformational change of fibroin from a random coil to a P structure (silk 11) at the whisker-matrix interface. This change seems to be induced by contact of fibroin molecules with a highly ordered surface of cellulose whisker.

• 出版日期2002-12-20