کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5184574 1381051 2011 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Light scattering study on the dynamic behaviour of cellulose inclusion complex in LiOH/urea aqueous solution
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Light scattering study on the dynamic behaviour of cellulose inclusion complex in LiOH/urea aqueous solution
چکیده انگلیسی

In our previous study, the rapid dissolution of cellulose in alkali/urea aqueous solution at low temperature induced by a dynamic self-assembly process has been demonstrated [1]. The cellulose solution was meta-stable, and its stability could be influenced by system fluctuations (temperature, concentration or time). In the present work, cellulose dissolved in 4.6wt% LiOH/15.0wt% urea aqueous solution pre-cooled to −12 °C was studied by means of dynamic light scattering (DLS). The results revealed that cellulose existed as single inclusion complexes (ICs) associated with LiOH and urea hydrate which could surround the ICs at their surface. And the ICs were stiff, as revealed by results from transmission electron microscopy (TEM) and light scattering (LS). When there was a system fluctuation, the self-association of cellulose with each other took place, resulted from the destruction of the urea shell, and leading to the aggregation of the ICs. For that reason, the ICs stability could be evaluated by the aggregation behaviour. In our findings, the hydrodynamic radius (Rh,app) for the cellulose dispersion in dilute solution shifted to higher values with an increase of the temperature, the concentration or the storage time, indicating an IC aggregation phenomenon.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 52, Issue 17, 3 August 2011, Pages 3857-3864
نویسندگان
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