ORIGINAL PAPER Influence of cellulose gel matrix on BMIMCl ionic liquid dynamics and conductivity J. Kaszyn ´ska . A. Rachocki . M. Bielejewski . J. Tritt-Goc Received: 21 October 2016 / Accepted: 13 February 2017 / Published online: 27 February 2017 Ó Springer Science+Business Media Dordrecht 2017 Abstract Fast field-recycling magnetic resonance relaxometry (FFC NMR) was applied to measure the spin-lattice relaxation time, T 1 , of protons in pure ionic liquid (IL) 1-butyl-3-methylimidazolium chloride (BMIMCl) and when confined in cellulose (Cell) ion gel (Cell/BMIMCl) at different temperatures and different Larmor frequencies. The rotational and translational contributions were taken to interpret the relaxation data of neat BMIMCl and were described by Woessner’s and Torrey’s theoretical models, respectively. The ionic liquid–cellulose matrix inter- action detected in 10 wt% polymer-ion gel was interpreted on the basis of a dynamical process called reorientation mediated by translational displacements (RMTD), which allow explanation of the significant slowing of the dynamics of IL cations at cellulose surfaces. Two types of cation diffusion were identified in this gel: a long-range translational diffusion within large cavities of the Cell matrix and diffusion occur- ring at the polymer surface. The correlational time constants and self-diffusion coefficients of the BMIMCl ionic liquid in bulk-like state and interaction with the cellulose matrix surface were determined. The conductivity measurements performed for pure IL and that confined in the Cell/BMIMCl ion gel show that the gelation only results in a small decrease of the ionic conductivity. Keywords Cellulose  Ionic liquid  Ion gel  NMR relaxometry  NMR diffusion  Conductivity Introduction Ionic liquids (ILs) are salts of organic and inorganic cations and anions whose melting point is usually below 100 °C. Among them a special class of ILs is room temperature ionic liquids (RTILs), which pre- serve the liquid state at room temperature and below. The ions in ILs are surrounded by oppositely charged ions and may form clusters or aggregates that are stabilized by ionic interactions, van der Waals forces and hydrogen bonds (Inman and Lovering 2013). The most important properties of ILs are negligible vapor pressure, non-flammability and generally high thermal stability, high conductivity and a wide electrochem- ical potential window (Hapiot and Lagros 2008; Galinski et al. 2006). Owing to the unique properties J. Kaszyn ´ska  A. Rachocki  M. Bielejewski  J. Tritt-Goc (&) Institute of Molecular Physics, Polish Academy of Sciences, M. Smoluchowskiego 17, 60-179 Poznan, Poland e-mail: jtg@ifmpan.poznan.pl J. Kaszyn ´ska e-mail: bje@ifmpan.poznan.pl A. Rachocki e-mail: radam@ifmpan.poznan.pl M. Bielejewski e-mail: bielejewski@ifmpan.poznan.pl 123 Cellulose (2017) 24:1641–1655 DOI 10.1007/s10570-017-1223-z