Synthesis, structure and properties of oligomeric ionic liquids of highly branched structure and special features of their self-arrangement

Valery V. Shevchenko

Institute of Macromolecular Chemistry of the National Academy of Sciences of Ukraine, Kyiv, Ukraine

Alexandr V. Stryutsky

Institute of Macromolecular Chemistry of the National Academy of Sciences of Ukraine, Kyiv, Ukraine

Mariana A. Gumenna

Institute of Macromolecular Chemistry of the National Academy of Sciences of Ukraine, Kyiv, Ukraine

Nina S. Klimenko

Institute of Macromolecular Chemistry of the National Academy of Sciences of Ukraine, Kyiv, Ukraine

Valeri V. Klepko

Institute of Macromolecular Chemistry of the National Academy of Sciences of Ukraine, Kyiv, UkraineORCID:

Synthesis, features of structural organization and behavior in aqueous solution of amphiphilic reactive aprotic cationic oligomeric ionic liquids obtained on the basis of a mixture of oligomeric amino- and hydroxyl-containing silsesquioxanes were considered. The dependence of the glass transition temperature, the value of ionic conductivity, self-organization in dilute aqueous solutions and the ζ-potential on the length of the alkyl substituent near the quaternary nitrogen atom in the composition of the synthesized compounds was shown. It was found that quaternization of the tertiary nitrogen atom of the starting oligomer causes a sharp decrease in the glass transition temperature. The value of the latter increases with an increase in the length of the hydrophobic alkyl fragments due to their association. In this case the ionic conductivity under anhydrous conditions decreases and at temperatures above 100°C drops by almost an order of magnitude. The maximum conductivity was reached for the oligomeric ionic liquid with the short alkyl chain and its value was 10-3 S/cm at 120oC. In dilute aqueous solutions the synthesized oligomeric ionic liquids with the short alkyl chain form aggregates with an average size of 100 nm while increasing the length of the alkyl chain prevents aggregation of silsesquioxane nuclei and leads to formation of unimolecular micelles with an average size of 3 nm.



1.            Xu W., Ledin P.A., Shevchenko V.V. et al. The architecture, assembly, and emerging applications of branched functional polyelectrolytes and poly(ionic liquids). ACS Appl. Mater. Interfaces. 2015. 7(23): 12570–2596.
2.            Tsukruk V.V. Dendritic macromolecules at interfaces. Adv. Mater. 1998. 10(3): 253–257.<253::AID-ADMA253>3.0.CO;2-E
3.            Korolovych V.F., Ledin P.A., Stryutsky A. et al. Assembly of amphiphilic hyperbranched polymeric ionic liquids in aqueous media at different pH and ionic strength. Macromolecules. 2016. 49(22): 8697–8710.
4.            Korolovych V.F., Erwin A., Stryutsky A. et al. Thermally responsive hyperbranched poly(ionic liquid)s: Assembly and phase transformations. Macromolecules. 2018. 51(13): 4923–4937.
5.            Shevchenko V.V., Stryutsky A.V., Klymenko N.S. et al. Protic and aprotic anionic oligomeric ionic liquids. Polymer. 2014. 55(16): 3349–3359.
6.            Shevchenko V.V., Stryutsky A.V., Sobko O.A. et al. Amphiphilic protic anionic oligomeric ionic liquids of hyperbranched structure. Polymer Sci. B. 2017. 59(4): 379–391.
7.            Tanaka K., Chujo Y. Advanced functional materials based on polyhedral oligomeric silsesquioxane (POSS). J. Mater. Chem. 2012. 22(5): 1733–1746.
8.            Tanaka K., Chujo Y. Chemicals-inspired biomaterials: developing biomaterials inspired by material science based on POSS. Bull. Chem. Soc. Jpn. 2013. 86(11): 1231–1239.
9.            Manickam S., Cardiano P., Mineo P.G., Lo Schiavo S. Star-shaped quaternary alkylammonium polyhedral oligomeric silsesquioxane ionic liquids. Eur. J. Inorg. Chem. 2014. 2014(16): 2704–2710.
10.          Majumdar P., Lee E., Gubbins N. et al. Synthesis and antimicrobial activity of quater-nary ammonium-functionalized POSS (Q-POSS) and polysiloxane coatings containing Q-POSS. Polymer. 2009. 50(5): 1124–1133.
11.          Maeda D., Ishii T., Kaneko Y. Effect of lengths of substituents in imidazolium groups on the preparation of imidazolium-salt-type ionic liquids containing polyhedral oligo-meric silsesquioxane structures. Bull. Chem. Soc. Jpn. 2018. 91(7): 1112–1119.
12.          Esperança J.M.S.S., Tariq M., Pereiro A.B. et al. Anomalous and not-so-common be-havior in common ionic liquids and ionic liquid-containing systems. Front. Chem. 2019. 7:450.
13.          Dong F., Lu L., Ha C. Silsesquioxane-containing hybrid nanomaterials: fascinating platforms for advanced applications. Macromol. Chem. Phys. 2019. 220(3): 1800324.
14.          Chen F., Lin F., Zhang Q. et al. Polyhedral oligomeric silsesquioxane hybrid polymers: well-defined architectural design and potential functional applications. Macromol. Rapid Commun. 2019. 40(17): 1900101.
15.          Li W., Wang D., Han D., Sun R., Zhang J., Feng Sh. New polyhedral oligomeric silsesquioxanes-based fluo-rescent ionic liquids: synthesis, self-assembly and application in sensors for detecting nitroaromatic explosives. Polymers. 2018. 10(8): 917.
16.          Li L., Liu H. Rapid preparation of silsesquioxane-based ionic liquids. Chem. Eur. J. 2016. 22(14): 4713–4716. 1
17.          Dule M., Biswas M., Paira T.K. Mandal T.K. Hierarchical nanostructures of tunable shapes through self-aggregation of POSS end-functional polymer and poly(ionic liquid) hy-brids. Polymer. 2015. 77. P. 32–41.
18.          Mori H., Lanzendӧrfer M.G., Müller A.H.E., Klee J.E. Silsesquioxane-based nanoparticles formed via hydrolytic condensation of organotriethoxysilane containing hydroxy groups. Macromolecules. 2004. 37(14): 5228–5238.
19.          Mori H., Müller A.H.E., Klee J.E. Intelligent colloidal hybrids via reversible pH-induced complexation of polyelectrolyte and silica nanoparticles. J. Am. Chem. Soc. 2003. 125(13): 3712–3713.
20.          Matějka L., Dukh O., Brus J., Simonsick Jr. W.J., Meissner B. Cage-like structure formation during sol-gel polymerization of glycidyloxypropyltrimethoxysilane. Journal of Non-Crystalline Solids. 2000. 270(1–3): 34–47.
21.          Eisenberg P., Erra-Balsells R., Ishikawa Y. et al. Cagelike precursors of high-molar-mass silsesquioxanes formed by the hydrolytic condensation of trialkoxysilanes. Macromolecules. 2000. 33(6): 1940–1947.
22.          Ishii T., Mizumo T., Kaneko Y. Facile preparation of ionic liquid containing silsesqui-oxane framework. Bull. Chem. Soc. Jpn. 2014. 87(1): 155–159.
23.          Ishii T., Enoki T., Mizumo T. et al. Preparation of imidazolium-type ionic liquids con-taining silsesquioxane frameworks and their thermal and ion-conductive properties. RSC Adv. 2015. 5(20): 15226–15232.
24.          Harada A., Koge S., Ohshita J., Kaneko Y. Preparation of a thermally stable room temperature ionic liquid containing cage-like oligosilsesquioxane with two types of side-chain groups. Bull. Chem. Soc. Jpn. 2016. 89(9): 1129–1135.
25.          Tereshchenko T.A., Shevchuk A.V., Shevchenko V.V., Snegir S.V., Pokrovskii V.A. Alkoxysilyl derivatives of polyhedral oligosilsesquioxanes containing amino and hydroxyl groups and sol-gel hy-brid materials on their basis. Polym. Sci. Ser A. 2006. 48(12): 1248–1256.
26.          Bliznyuk V.N., Tereshchenko T.A., Gumenna M.A. et al. Structure of segmented poly(ether urethane)s containing amino and hydroxyl functionalized polyhedral oligo-meric silsesquioxanes (POSS). Polymer. 2008. 49(9): 2298–2305.
27.          Shevchenko V.V., Gumenna M., Lee H. Klimenko N., Stryutsky O., Trachevsky V., Korolovych V., Tsukruk V.V. Reactive amphiphilic aprotic ionic liquids based on functionalized oligomeric silsesquioxanes. Bull. Chem. Soc. Jpn. 2021. 94(9): 2263—2271. DOI:
28.          Shevchenko V.V., Gumennaya M.A., Shevchuk A.V., Gomza Yu.P., Klimenko N.S., Boichuk V.V. The effect of terminal groups on the structure and properties of oligosilsesquioxanes. Polymer Sci. B. 2009. 51(1–2): 46–54.
29.          Shaplov A.S., Marcilla R., Mecerreyes D. Recent advances in innovative polymer elec-trolytes based on poly (ionic liquid)s. Electrochimica Acta. 2015. 175: 18–34.
30.          Kyritsis A., Pissis P., Grammatikakis J. Dielectric relaxation spectroscopy in poly(hydroxyethyl acrylates)/water hydrogels. J. Polym. Sci. B. 1995. 33(12): 1737–1750.
31.          Gao B., Zhang Q., Wang X. and et al. A “self-accelerating endosomal escape” siRNA delivery nanosystem for significantly suppressing hyperplasia via blocking the ERK2 pathway. Biomater. Sci. 2019. 7(8): 3307–3319.
32.          Wu Y., Li Z. The perspectives of using unimolecular micelles in nanodrug formulation. Ther. Deliv. 2019. 10(6): 333–335.
33.          Liu X., Fan X., Jiang L. et al. Biodegradable polyester unimolecular systems as emerg-ing materials for therapeutic applications. J. Mater. Chem. B. 2018. 6(35): 5488–5498.
34.          Bhattacharjee S. DLS and zeta potential — What they are and what they are not? J. Contr. Release. 2016. 235: 337–351.