Properties of aqueous solutions of hydroxyethyl cellulose-poly(N-vinylformamide) blends and of the related composite films

The rheological properties of dilute and moderately concentrated aqueous solutions of hydroxyethyl cellulose-poly(N-vinylformamide) blends are studied. The stress-strain characteristics of the composite films are estimated. Dynamic mechanical analysis, the thermomechanical method, and the method of solvent-vapor sorption are used to determine the composition ranges of polymer compatibility and the temperatures of relaxation transitions in composite films. The structural organization of composite films is studied via X-ray diffraction analysis. The incorporation of one polymer into the matrix of another polymer entails changes in crystallization of the polymer dominating in the composite with respect to weight and causes an increase in the imperfectness of the crystal structure.