CRYSTALLINE-AMORPHOUS PHASE-TRANSITION OF A POLY(ETHYLENE GLYCOL) CELLULOSE BLEND

Poly(ethylene glycol) (PEG)/cellulose (CELL) blends prepared from solutions in dimethyl sulfoxide-paraformaldehyde were studied with X-ray diffraction and thermal analysis. PEG in the blend was found to be crystalline at room temperature. However, when the temperature was raised to PEG's melting point, PEG blended with CELL did not melt into the liquid state as in the case of pure PEG but changed to an amorphous solid state. infrared spectroscopy investigations suggested that there were quite strong intermolecular hydrogen bonds formed between PEG and CELL in the blends. PEG's molecules probably are tied to the semirigid CELL chains so strongly by the hydrogen bonds that they cannot change to a liquid state but change to the amorphous state by thermal vibration at high temperatures.