Microwave-Assisted Derivatization of Cellulose, 2 - The Surprising Effect of the Structure of Ionic Liquids on the Dissolution and Acylation of the Biopolymer

作者：El Seoud Omar A^*; da Silva Valdineia C; Possidonio Shirley; Casarano Romeu; Areas Elizabeth P G; Gimenes Paula

来源：Macromolecular Chemistry and Physics, 2011, 212(23): 2541-2550.

DOI：10.1002/macp.201100348

• cellulose dissolution in ionic liquids
• functionalization of polymers
• imidazole-based ionic liquids
• microwave-assisted acylation of cellulose
• rheology of and solvatochromism in ionic liquids

The relevance of the structure of ILs for the dissolution and microwave-assisted acylation of eucalyptus cellulose is reported. The 1-R-3-methylimizadolium-X ILs with X = Cl, Ac and R = 1-butyl, 2-methoxyethyl, 1-heptyl, and 3,6-dioxa-(1-heptyl) are studied: C4MeImX, C3OMeImX, C7MeImX, and C5O2MeImX. The dissolution efficiencies are C3OMeImAc > C4MeImAc and C7MeImAc > C5O2MeImAc, i.e., they depend on the length of the side chain. This surprising result is corroborated by (i) cellulose acylation by ethanoic, butanoic, and hexanoic anhydride; (ii) the energy of viscous flow of the ILs; (iii) the solvatochromic properties of the ILs. Our results show that C3OMeImAc and C4MeImAc are distinct from C7MeImAc and C5O2MeImAc, due to chain-dependent hydrogen bonding and hydrophobic interactions.

• 出版日期2011-12-1