Papers by Keyword: Ionic Liquid (IL)

Abstract: A series of regenerated cellulose (RC) nanocomposites which were incorporated with the layered silicate mica were successfully prepared via ionic liquid. The effect of the mica loadings was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The mechanical properties which were investigated via tensile testing indicated that upon the introduction of the mica displayed a significant enhancement on the mechanical stability of the RC. The results showed the potential of mica to reinforce the RC polymers matrix.

Abstract: Solid polymer electrolytes (SPEs) with poly (vinyl) chloride (PVC) doped with a fixed amount of ammonium trifluoro methane sulfonate (NH₄Tf) and with varying concentrations of ionic liquid butyltrimethyl ammonium bis (trifluoromethyl sulfonyl) imide (Bu₃MeNTf₂N) were synthesised via solution cast technique. PVC-NH₄Tf-Bu₃MeNTf₂N-based SPEs with 15 weight % Bu₃MeNTf₂N exhibit conductivity of 1.56 x 10^-4 Scm^-1 at room temperature. The ionic conductivity is attributed to the dissociation of NH₄Tf facilitated by Bu₃MeNTf₂N. Results of XRD indicate that the most amorphous film has the highest conductivity and this is corroborated by the results of DSC. FTIR spectra revealed that Bu₃MeNTf₂N has weak interaction suggesting that it acts mainly as a lubricant to facilitate polymer segmental motion.

Abstract: In recent decades, dependence on fossil fuels resources has shifted into derivation of cellulose based materials to replace the non-renewable resources. Lignocellulosic biomass is the most abundant feedstock on earth and is one of the promising renewable and sustainable resources. In the present study, simple preparation of nanocellulose particles by using ionic liquid (1-butyl-3-methylimidazolium hydrogen sulfate) has been introduced by investigating the influence of reaction temperature (room temperature and heat treated at 90°C). The resultant samples were characterized using X-Ray Diffraction (XRD) and Fourier-Transform Infrared Spectroscopy (FTIR). Interestingly, it was found that the high crystallinity sample could be synthesized at temperature of 90°C. The reason might be attributed to ionic liquid enter into the space between cellulose chains and caused cellulose molecules progressively swelled up when heated. Consequently, amorphous regions of cellulose were dissolved by ionic liquid and crystalline parts of cellulose were leave in the cellulose structure. From the XRD data, it could be observed that sharper crystalline peak and higher crystallinity index (CrI) present within heat-treated samples which corresponded to higher crystalline structure of cellulose I. While the broader peak and lower CrI of untreated cellulose samples indicated lower crystalline structure of cellulose I. Pretreatment of cellulose with ionic liquid can provides a facile approach for the preparation of nanocellulose particles with high crystallinity.

Abstract: Some results of tests of the thermal stability (and volatility) of selected ionic liquids pondered as lubricating substances in comparison with typical lubricating, mineral and synthetic oils, are presented in the article. The research was carried out within the framework of PBR/15–249/2007/WAT–OR00002904 Research Project Financed by the Ministry of Science and Higher Education, during 2007–2011 [1]. The obtained results confirmed high thermal resistance of ionic liquids. It makes it possible to use the liquids as high temperature lubricating substances. At the same time, it has been stated that the thermal resistance of ionic liquids depends on the composition and chemical structure of anion and cation.

Abstract: The sisal cellulose was dissolved in ILs under optimal conditions of 150°C and 400W. The structure of sisal cellulose was changed from cellulose I to cellulose II, accompanied with the decrease of crystallinity through XRD, FT-IR analysis. According to the result of GPC, molecular weight distribution became more uniformly and narrow. This is because intra-and inter-hydrogen bond existed in cellulose were destroyed during the dissolution process in ILs. And the regenerated cellulose possessed better properties than the former, which could broaden the application fields of natural cellulose.

Abstract: Carbon-coated nickel nanoparticles were synthesized by solvothermal method in 1-buty-3-methylimidazolium tetrafluoraborate ionic liquid. The obtained products are characterized by X-ray powder diffraction (XRD), Raman spectroscopy, infrared spectroscopy and transmission electron microscopy (TEM). The magnetic properties of carbon-coated nickel nanoparticles have been investigated by vibrating sample magnetometry (VSM). It was found that the carbon-coated nickel nanoparticles showed excellent magnetic properties. The present route may give researchers more choices for preparing other carbon-coated transition metal nanoparticles.

Abstract: Poly(vinylidene fluoride) (PVDF)/1-butyl-2,3-dimethylimidazolium Tetrafluoroborate ([BMMIm][BF4]) flat sheet membranes were made via thermally induced phase separation (TIPS) melt technology, and [BMMIm][BF4]) was used as a diluent. The prepared membranes were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) and etc. Furthermore, [BMMIm][BF4] as a liquid-diluent was effectively recovered by vacuum distillation. In conclusion, this work may provide a green and sustainable preparation method to produce PVDF membranes via TIPS.

Abstract: Ionic liquid 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) was used to dissolve cellulose and cellulose was regenerated from the solution by two different methods. Original cellulose (OC) and regenerated cellulose have different crystallinity. The morphological characteristic of different crystallinity cellulose was analyzed by the scanning electron microscopy (SEM). The cellulose pyrolysis experiment was performed on a horizontal tube furnace reactor and a wire mesh reactor. The pyrolytic char was prepared at 300°C with 50% char yield. Surface structure of original char and water washed char prepared from above two reactors was analyzed by the XPS. The results reveal the impact of secondary reaction between the volatile and char and crystallinity on the char structure during cellulose pyrolysis.

Abstract: Room temperature ionic liquids are new emerging materials. However, ionic liquids are applied mainly in Chemistry field and are rarely used in microfluidics although they are also good photoelectric medium material. Here ionic liquids are used as a new type of microfluidic fluids, and the flow performance of ionic liquids under electromagnetic drive is researched so as to promote their application in microfluidics. The flow rates can be up to 3.9μl/s and 9.7μl/s at applied direct-current potentials of 6 and 8 V, respectively, in a 0.5T magnetic field. Meanwhile the time performances of ionic liquids in electromagnetic field are researched. The experiment data are in accord with the theory results calculated by the numerical simulation.

Abstract: Depolymerization of DGEBA/EDA Epoxy Resin was carried out in a microwave reactor, heated for definitized time. Experimental results showed that the products obtained are phenol, bisphenol A, isopropyl phenol. Liquid products were analyzed by high performance liquid chromatography (HPLC) and the standard curve was established by the pure samples and used it to quantify. The results show that the maximum yields of phenol, bisphenol A, isopropyl phenol are 81%,50%,12%.The residual solid after depolymerization were analyzed by infrared spectroscopy and confirmed that it was residual epoxy resin solid. Depolymerization ratio and yields of main products increase with the increase of reaction temperature and time. The most effective medium is BmimCl and the depolymerization ratio can reach 92%, and the test by infrared spectroscopy shows that BmimCl is stable , It can be used for many times.