E. S. Sashina

Structure and solubility of natural silk fibroin

The solubility of silk fibroin in aqueous-salt, aqueous-organic, and organic media is analyzed. Factors affecting the formation of the secondary structural organization of fibroin in solutions and in the solid state after the recovery from solutions are analyzed.

Synthesis and dissolving power of 1-Alkyl-3-methylpyridinium-based ionic liquids

Abstract1-Alkyl-3-methylpyridinium-based ionic liquids with substituents from C2 to C10 and anions Cl− and Br− were synthesized, and their dissolving power toward the cellulose was investigated. The results of quantum-chemical calculations of molecules of ionic liquids are presented.

Study of a possibility of applying the films of the silk fibroin and its mixtures with synthetic polymers for creating the materials of contact lenses

Light and gas permeability, antimicrobic and physico-mechanical properties are studied of the films from the mixtures of fibroin with the synthetic polymers.

Preparation and properties of films of fibroin-polyvinyl alcohol blends from solutions in hexafluoroisopropanol

The compatibility of fibroin with polyvinyl alcohol in blend films prepared from a common organic solvent, hexafluoroisopropanol, was studied by IR spectroscopy and DSC.

1-Alkyl-3-Methylpyridinium Halide Structural Features Studied by Vibrational Spectroscopic Methods

A series of ionic liquids based on 1-alkyl-3-methylpyridinium halides were studied by Raman and IR spectroscopy. Results from calculations and experimental methods were used to interpret the spectra.

Thermochemistry of mixing imidazole-based ionic liquids with water and organic solvents

The results of the calorimetric studies of the enthalpies of mixing of some ionic liquids, 1-butyl-3-methylimidazolium chloride and acetate, with water, pentanol, dimethyl sulfoxide and dimethylformamide are presented. Protic solvents interact with the ionic liquid anion, wheras aprotic, with the cation. The mixing enthalpy depends on the dissociation degree of the ionic liquid.

Thermochemical study on the dissolution and regeneration of fibroin from solutions in imidazole-based ionic liquids

The enthalpies of dissolution of fibroin in imidazole-based ionic liquids were determined, and the contribution of polymer crystal structure decomposition to the enthalpy of dissolution was estimated. The heat of mixing of imidazole ionic liquid with water was described.

Silver nanoparticles on fibers and films of Bombyx mori silk fibroin

Possibility of obtaining silver nanoparticles on fibers and films of silk fibroin was studied. A comparative assessment of the effect of reducing agents on the morphology and size of silver particles on the fiber surface was made.

Pyridinium-Based Ionic Liquids — Application for Cellulose Processing

Over the last two decades new direct solvents for cellulose and other natural polymers have been actively explored; these are ionic liquids (ILs). The unique properties of this new class of compounds allow the use of ILs in various fields of science and technology, among which the use of ILs as the reaction medium for biomass processes occupies an important place [1-3], especially for cellulose dissolution [4-13], and the dissolution of other natural polymers [14], and produces from their solutions new biodegradable materials, including films, fibres and membranes [15].

Prospects for Producing New Biomaterials Based on Fibroin

Methods for preparing solutions and materials based on the biopolymer fibroin were discussed. Thermal hydrolysis of fibroin at 220-300°C produced a mixture of water-soluble amino acids, dipeptides, and diketopiperazines. The diketopiperazine content increased with increasing hydrolysis temperature. Dissolution of fibroin in ionic liquids formed thixotropic solutions with properties that depended on the dissolution temperature. The ordering of films produced from the solutions depended on the contact time with the precipitant.