Studies in chemically modified celluloses. III. Estimation of free carboxylic acid groups in oxycellulose

Various methods suggested for the determination of carboxyl groups in chemically modified celluloses suffer from some drawbacks. Attempts have been made to overcome the drawbacks of some of these methods. The influence of alkali‐sensitive reducing groups, enediol groups, and lactones on the carboxyl estimation is discussed and the importance of borohydride treatment of the oxycelluloses before the estimation of carboxyl groups by alkali titration method or by iodometric method is stressed. The usefulness and the limitations of both methods are pointed out.