AbstractThe thermal depolarization current technique is applied to plasticized and unplasticized regenerated cellulose films. In unplasticized cellulose, two depolarization current bands are observed. The band with a current maximum occurring near 298°K (Tm), and with an activation energy,U, of 0.57 eV, is believed to be related to the second‐order transition which is known to occur in dry cellulose in the vicinity of 298°K. The second band, withTm= 215°K andU= 0.26 eV, is also present in the plasticized material, and possibly arises from primary hydroxyl group orientations. In cellulose films plasticized with glycerol, an intense band occurs at 271°K, withU= 0.51 eV, and is attributed to the plasticizer. A third band, occurring in the plasticized material near 300°K, has not been fully invest
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