The influence of activation on the solution state of cellulose dissolved in N-methylmorpholine-N-oxide-monohydrate

The solution state of cellulose dissolved in N-methylmorpholine-N-oxide-mon ohydrate (NMMNO.MH) was investigated by static laserlight scattering. Speci al emphasis was placed on the potential influence of activation procedures. The light-scattering measurements were analysed in terms of Guinier-Zimm p lots. Molecular masses of the order of several million g mol(-1) were obser ved. This indicates that cellulose aggregates exist acid that the aggregate s comprise several hundred cellulose chains. The radii of gyration of these aggregates exceed 160 nm. The overall scattering functions can be separate d into two partial scattering contributions. This reflects a bimodal distri bution of the particulate phase, consisting of large and small aggregates. Activation of cellulose prior to dissolution leads to particles consisting of significantly fewer cellulose molecules than without activation, However , the size of the aggregates does not change significantly. (C) 1999 Elsevi er Science Ltd. All rights reserved.