PROPERTIES OF CELLULOSIC PULPS OBTAINED B Y OXIDATION SOLVOLYSIS FROMSPRUCE, POPLAR AND EUCALYPTUS-GLOBULUS - COMPARISON OF THEIR TEAR RESISTANCE

Strength characteristics of poplar, eucalyptus globulus and spruce oxy gen-organo-solv pulps are lower compared to the corresponding kraft pu lps. Dehydration properties of solvents are responsible for the lack o f fibre flexibility and hydrolysis of polyoses in the fibre weak point s. Oxidation by oxygen implies dislocation area formation. Dislocation areas allow fibre cut during beating and diminution of tearing streng th. Alkaline treatment improves strength properties oi poplar pulp due to the solvation of polyoses, which increases fibre flexibility. On t he contrary, the same treatment has no effect on spruce and eucalyptus pulps. These differences of behaviour can be explained by the morphol ogical specific structures of each wood.