The Effectss Of Polyalcohol On The Structure And Properties Of Silk Fibroin

The effects of polyhydric alcohols on the structure of silk fibroin were studied in this paper. The polyhydric alcohols were included ethylene glycol, propylene glycol, butanediol, glycerol, Erythritol, xylitol, D-sorbitol and inositol. The solubility, mechanical properties and transparency of silk fibroin films were discussed. The results showed that the blend films had the potential as repairing materials for cornea.The blend films casted from the mixture solution of silk fibroin and polyhydric alcohols (ethylene glycol, propylene glycol, butanediol, glycerol, Erythritol, xylitol, D-sorbitol or inositol). The structure, solubility, mechanical properties and light transmittance of the blend films were measured. X-ray diffraction, FT-IR indicated that glycerol, Erythritol, xylitol, D-sorbitol or inositol induced the structure of silk fibroin from random coil to Silkâ… . While for the binary alcohol, the structure of silk fibroin changed from random coil to Silkâ… or Silkâ…¡which was related to the content. It was concluded that the structure of silk film was related to Hydrophile-Lipophile Balance(HLB) of the adding alcohols. When the alcohol's HLB > 9.85, the silk fibroin mainly formed Silkâ… structure; when the HLB value<8.9, the silk fibroin mainly formed Silkâ…¡structure; when the HLB value was between 8.9 and 9.85, the structure of silk fibroin had relationship with the content of the alcohols. That is the structure of silk fibroin mainly transformed Silkâ… with low content of alcohols, on the other way, the structure of silk fibroin mainly transformed Silkâ…¡with high content of alcohols. The results also showed the alcohols can solve the problem of solubility of silk film. The hygroscopic alcohols could promoted the toughness of silk fibroin in the dry state. In the wet state, the mechanical properties and light transmittance of the blend films added liquid alcohols were similar to human cornea. The other blend films added solid-state alcohol with the content of 1/10 were also had good mechanical properties and light transmittance suit human cornea. the silk/polyhydric alcohol blend films had a great potential to act as repairing materials for cornea. The degradation rate of silk fibroin films with different structures was measured in this paper. The effects showed that the blend film with the structure of Silkâ… had the fastest degradation rate. When the blend films had the same structure of Silkâ…¡, the degradation rate of the pured silk film treated with ethanol was lowest; the degradation rate of the silk/butanediol blend membrane was fasted; and the degradation rate of the silk/butanediol blend film treated with ethanol was between the above two.