کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7791089 1500646 2014 35 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
True molecular solutions of natural cellulose in the binary ionic liquid-containing solvent mixtures
ترجمه فارسی عنوان
راه حل های مولکولی واقعی سلولز طبیعی در مخلوط های حلال حاوی مایع یونی دوتایی
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
چکیده انگلیسی
Evidence is presented for the first time of true molecular dissolution of cellulose in binary mixtures of common polar organic solvents with ionic liquid. Cryogenic transmission electron microscopy, small-angle neutron-, X-ray- and static light scattering were used to investigate the structure of cellulose solutions in mixture of dimethyl formamide and 1-ethyl-3-methylimidazolium acetate. Structural information on the dissolved chains (average molecular weight ∼5 × 104 g/mol; gyration radius ∼36 nm, persistence length ∼4.5 nm), indicate the absence of significant aggregation of the dissolved chains and the calculated value of the second virial coefficient ∼2.45 × 10-2 mol ml/g2 indicates that this solvent system is a good solvent for cellulose. More facile dissolution of cellulose could be achieved in solvent mixtures that exhibit the highest electrical conductivity. Highly concentrated cellulose solution in pure ionic liquid (27 wt.%) prepared according to novel method, utilizing the rapid evaporation of a volatile co-solvent in binary solvent mixtures at superheated conditions, shows insignificant cellulose molecular aggregation.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbohydrate Polymers - Volume 112, 4 November 2014, Pages 125-133
نویسندگان
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