抄録
Viscose rayon is pretreated to imbibe various liquids and then acetylated in fibrous form with the following acetylation bath: acetic anhydride, diluent and sulfuric acid (in form of sullo acetic acid). The rate of acetylation differs widely by the conditions of acetylation. It depends upon the kind of imbibition and diluent liquid and catalyst. The first step of liquid phase fibrous aeetylation consists in the displacement of the imbibition liquid with the acetylating bath. It seems that the easiness of the displacement, which depends upon the above mentioned factors, is dominating in the rate of acetylation. Cohesive energy, densities of various liquids are calculated and the easiness of the displacement discussed.