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Abstract The synthesis and characterization of a series of polyurethane ionenes using a non‐isocyanate approach is disclosed. Imidazole‐capped, urethane‐containing prepolymers are prepared by first reacting carbonyl diimidazole (CDI) with several poly(propylene glycol) (PPG) diols with variable molecular weight, followed by subsequent reaction with 3‐aminopropylimidazole (API). Polymerization with 1,4‐dibromomethylbenzene followed by anion exchange resulted in the desired polyurethane ionenes bearing the [NTf₂] counteranion as a series of viscous liquids. NMR and FTIR spectroscopy are used to characterize the intermediates and final ionenes, including molecular weight determination by end‐group analysis. A single glass transition temperature (T_g), as determined by differential scanning calorimetry (DSC), is observed for each ionene (−38 to −64 °C) with theT_gdecreasing with increasing PPG molecular weight. Thermogravimetric analysis (TGA) indicated a two‐step decomposition for each ionene, with the first being degradation of the PPG segment, followed by the urethane/ionic segment. Microphase separation is observed from x‐ray scattering profiles with Bragg distances that increased with increasing PPG molecular weight. Ionic conductivity is found to be inversely dependent upon DSCT_gat lower temperatures (RT and below); however, at higher temperatures, conductivity appears to be more dependent upon the ability of ionic aggregates caused by phase separation to interact. 

A non-isocyanate synthetic route was used to generate 20 different ionic liquids containing either a carbamate or thiocarbamate functional group. 

Dual ionic liquid-substituted cellulosic materials were prepared by coupling a series of alkyne-terminated imidazoles with variable carbon spacer with azide-functionalized cellulose, followed by quaternization and anion exchange. All three of the [NTf2]-bearing cellulosic materials exhibited Tg values below zero and could be cast as flexible films, which exhibited stress at break values exceeding 2.3 MPa with strain at break values up to 252%. X-ray scattering analyses indicated the amorphous nature of the cellulosic materials with three scattering peaks observed, from high-to-low q, corresponding to the amorphous halo, anion-to-anion distance, and the distance between ion aggregates, respectively. The highest degree of ionic aggregation was found to exist in the CELL-C12-NTf2 material, presumably due to the longer alkyl tethers causing more uniformity in the interaggregate spacing. The conductivity of the films was found to be on the order of 10−5−10−6 S/cm at 30 °C. A slower increase in conductivity with temperature was observed for systems where ionic aggregation was the strongest.