Phase Transitions and Crystal Structures of Ionic Plastic Crystals Comprising Quaternary Ammonium Cations and Carborane Anion

Molecularly imprinted polymers have emerged as cost-effective and rugged artificial selective sorbents for combination with different sensors. In this study, quaternary ammonium cations, as functional monomers, were systematically evaluated to design imprinted polymers for glyphosate as an important model compound for electrically charged and highly water-soluble chemical compounds. To this aim, a small pool of monomers were used including (3-acrylamidopropyl)trimethylammonium chloride, [2-(acryloyloxy)ethyl]trimethylammonium chloride, and diallyldimethylammonium chloride. The simultaneous interactions between three positively charged monomers and glyphosate were preliminary evaluated using statistical design of the experiment method. Afterwards, different polymers were synthesized at the gold surface of the quartz crystal microbalance sensor using optimized and not optimized glyphosate-monomers ratios. All synthesized polymers were characterized using atomic force microscopy, contact angle, Fourier-transform infrared, and X-ray photoelectron spectroscopy. Evaluated functional monomers showed promise as highly efficient functional monomers, when they are used together and at the optimized ratio, as predicted by the statistical method. Obtained results from the modified sensors were used to develop a simple model describing the binding characteristics at the surface of the different synthesized polymers. This model helps to develop new synthesis strategies for rational design of the highly selective imprinted polymers and to use as a sensing platform for water soluble and polar targets.

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Self-Assembly of Shape-Tunable Oblate Colloidal Particles into Orientationally Ordered Crystals, Glassy Crystals and Plastic Crystals

Soft Matter ◽

10.1039/d1sm00343g ◽

2021 ◽

Author(s):

Jiawei Lu ◽

Xiangyu Bu ◽

Xinghua Zhang ◽

Bing Liu

Keyword(s):

Crystal Structures ◽

Self Assembly ◽

Colloidal Particles ◽

Building Blocks ◽

Fundamental Question ◽

The Self ◽

Plastic Crystals ◽

Self Assembled ◽

Glassy Crystals ◽

The Relationship

The shapes of colloidal particles are crucial to the self-assembled superstructures. Understanding the relationship between the shapes of building blocks and the resulting crystal structures is an important fundamental question....

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Crystal structures of three newN-halomethylated quaternary ammonium salts

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989015017181 ◽

2015 ◽

Vol 71 (10) ◽

pp. 1230-1235

Author(s):

Carolina Múnera-Orozco ◽

Rogelio Ocampo-Cardona ◽

David L. Cedeño ◽

Rubén A. Toscano ◽

Luz Amalia Ríos-Vásquez

Keyword(s):

Crystal Structures ◽

Intermolecular Interactions ◽

Quaternary Ammonium ◽

Quaternary Ammonium Salts ◽

Ammonium Salts ◽

Compound I ◽

Nlo Properties ◽

Π Interactions

In the crystals of the titleN-halomethylated quaternary ammonium salts, C19H23IN+·I−, (I) [systematic name:N-(4,4-diphenylbut-3-en-1-yl)-N-iodomethyl-N,N-dimethylammonium iodide], C20H25IN+·I−, (II) [systematic name:N-(5,5-diphenylpent-4-en-1-yl)-N-iodomethyl-N,N-dimethylammonium iodide], and C21H27IN+·I−, (III) [systematic name:N-(6,6-diphenylhex-5-en-1-yl)-N-iodomethyl-N,N-dimethylammonium iodide], there are short I...I−interactions of 3.564 (4), 3.506 (1) and 3.557 (1) Å for compounds (I), (II) and (III), respectively. Compound (I) crystallizes in the Sohncke groupP21as an `enantiopure' compound and is therefore a potential material for NLO properties. In the crystal of compound (I), molecules are linked by C—H...I−and C—H...π interactions which, together with the I...I−interactions, lead to the formation of ribbons along [100]. In (II), there are only C—H...I−interactions which, together with the I...I−interactions, lead to the formation of helices along [010]. In (III), apart from the I...I−interactions, there are no significant intermolecular interactions present.

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