A STUDY ON THE PREPARATION, STRUCTURE, AND PROPERTIES OF MICROCRYSTALLINE CELLULOSE

The preparation, structure, and properties of microcrystalline cellulo se (MCC) from rice straw were investigated by IR, x-ray, viscometry, p olarizing microscope, SEM, etc. The results are as follows: 1. The lev eling-off degree of polymerization (LODP) obtained from rice straw is about 80-150. The dimensions of MCC granules are 20-30 mu m length, 0. 5-0.8 mu m thick, and the crystallinity is about 80%. 2. The aqueous s uspension of a certain concentration of MCC can form a gel under the e ffect of shear force. The viscosity of MCC gel increased with an incre asing content of MCC in water. A sharper increase of viscosity occurre d in the 3-6% range. 3. The addition of one or two valence salts into the MCC gel increased the viscosity. 4. The viscosity of MCC gel has i ts maximum value at pH 8. 5. The MCC gel as an emulsifying agent can f orm a stable emulsion in the oil/water system when the ratio of oil/wa ter is below 6/4.