With terephthaloyl chloride lignins

Some results of the modification of lignin sulfonate Ultra B002 by reaction with terephthaloyl chloride are summarized in Table VI. The total hydroxyl content of the lignosulfonates as well as their derivatives are presented in Table VII. The hydrolytic resistance of selected products is evaluated in Table VIII. The results presented in Tables VI-VIII stress several advantages of the derivatives with terephthaloyl chloride. The modified lignin sulfonates were insoluble, or only very slightly soluble, in organic solvents. They were, however, soluble in dimethyl sulfoxide. Ordered structures were identified by X-ray studies (16,17). 

The modification of lignin sulfonates with terephthaloyl chloride produces new polymeric materials containing ester groups. This modification can be used to utilize lignins also for improvement of chemical fiber properties. This is presently under investigation. 

Table VII. Total Hydroxyl Content of Lignin Sulfonates and Their Derivatives with Terephthaloyl Chloride.

Table VIII. Hydrolytic Resistance of the Lignins Modified with Terephthaloyl Chloride...

Another potential lignin modification method concerns the reaction with difunctional acid chlorides, especially terephthaloyl chloride, to form cross-linked polymeric materials (1,10,14,20). Several studies have dealt with... 

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