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Information × Registration Number 0223U002396, 0122U002546 , R & D reports Title Development of effective, low-corrosion and environmentally friendly methods of chemical degradation or dissolution of biopolymer cellulose-like formations popup.stage_title Head Kuzmin Viktor Ye., Доктор хімічних наук Registration Date 16-02-2023 Organization Physico-Chemical Institute O. Bogatsky National Academy of Sciences of Ukraine popup.description2 Research objects – cellulose, tea fungal, paper. The main aiml of work is search for chemical systems (substances and their mixtures) and development methods for effective degradation or dissolution of biopolymer cellulose-similar formations. The solubility of microcrystalline cellulose (MCC), paper (100% cellulose), tea fungal in aqueous alkaline solutions of urea and/or thiourea was studied; electrolytes in dipolar aprotic media (lithium halides, N,N-dimethylacetamide (DMA), N,N-dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), as well as MCNS thiocyanate salts (M = Li, Na, K) in an aqueous environment. The obtained results indicate that by varying ratio of reagents and changing experiment conditions, it is possible to achieve almost complete dissolution of microcrystalline cellulose. So, studying systems 1. NaOH (8%); 2. NaOH (7%)/urea (12%); 3. NaOH (7%)/urea (12%)/ZnO (0.5%); 4. NaOH (9.5%)/thiourea (4.5%) and 5. NaOH (8%)/thiourea (6.5%)/urea (8%), it was established that MCC in an aqueous solution of NaOH (mixture 1 ) dissolves only by 44%. By adding urea (mixture 2) to this system, its solubility improves significantly and reaches 85%. And aqueous system containing NaOH/thiourea and NaOH/thiourea/urea (mixture 4 and 5) will increase solubility of MCC to 95-98%. It was found that when tea fungal is dissolved in NaOH (10%)/thiourea (6.5%)/urea (8%) system, its solubility achieve 88%. Paper (100% cellulose) in NaOH (9.5%)/thiourea (4.5%) and NaOH (8%)/thiourea (6.5%)/urea (8%) systems is dissolved by 90% and 95% , respectively. When [solvent/LiCl] system was studied, in which DMAA, DMF, and DMSO were used as solvents, it was established that MCC is best dissolved in DMAA/LiCl (S = 100%), while its solubility is much lower in DMFA/LiCl and DMSO/LiCl (S ≥ 20%). In M/SCN systems (M = K, Na, NH4), it was established that, regardless from concentration of sodium thiocyanate (55 wt.% or 60 wt.%), solubility of MCC is 6%. Product Description popup.authors Kamalov Herbert L. Pluzhnyk-Gladyr Serhiy M. Chihichin Dmytro G. popup.nrat_date 2023-02-16 Close