Effects of side groups on the entanglement network of cellulosic polysaccharides

The transient entanglement networks of cellulosic polysaccharides in concentrated solutions were characterized by the molecular weight between entanglements (M e) using dynamic viscoelasticity measurements. From the concentration dependence ofM e, M e for the cellulosic polysaccharides in the molten state (M e, melt) was estimated as the material constant reflecting the chain characteristics. The values of M e, meltwere compared among three cellulosic polysaccharides: cellulose, methylcellulose, and hydroxypropyl cellulose. Methylcellulose and hydroxypropyl cellulose were employed as cellulose derivatives having small and large side groups, respectively. It appeared that hydroxypropyl cellulose had significantly larger M e, melt compared with cellulose and methyl cellulose. However, the numbers of repeating glucose-ring units between entanglements were very close to each other among the three polysaccharides.