Novel ionic liquid crystals based on N-alkylcaprolactam as cations

Jing Yang; Qinghua Zhang; Laiying Zhu; Shiguo Zhang; Jian Li; Xiaoping Zhang; Youquan Deng

doi:10.1021/cm062675s

Novel ionic liquid crystals based on N-alkylcaprolactam as cations

Jing Yang
, Qinghua Zhang
, Laiying Zhu
, Shiguo Zhang
, Jian Li
, Xiaoping Zhang
, Youquan Deng

CAS - Lanzhou Institute of Chemical Physics
Lanzhou University
University of Chinese Academy of Sciences

Research output: Contribution to journal › Article › peer-review

43 Scopus citations

Abstract

A novel series of ionic liquids (ILs) based on N-alkyl-ε-caprolactam as cations [C_n-CP]⁺ (C_n = alkyl with different numbers of C atoms; n -6, 8, 10, 12, 16, or 18) containing toluene-p-sulfonate [TS]^- and methanesulfonate [MS]^- as anions have been synthesized via a one-step atom-economic reaction. Characterizations of these ILs by differential scanning calorimetry, polarizing optical microscopy, variabletemperature powder X-ray diffraction, etc., were conducted. The results showed that the caprolactambased ILs (n ≥ 8) were enantiotropic thermotropic liquid crystals, except for C₁₈-CPMS (monotropic), and displayed smectic A phases. Some properties, such as higher transition enthalpies (e.g., ΔH = 83.1 kJ/mol for C₁₈-CPTS), higher specific heat capacities (e.g., C_p = 2.85 J/g·K for C₁₆-CPTS) and higher heat storage densities (e.g., sensible heat storage density E_s = 262.81 MJ/m³ for C₁₆~CPTS; latent heat storage density E₁ -146.0 MJ/m³ for C₁₈-CRTS), were observed. Fluorescence measurements showed that the homologous C_n-CPTS ILs exhibited strong fluorescence behavior. Finally, the test of acute toxicity toward rats showed that these new ILs were less toxic than the popular [BMIm]BF₄ IL.

Original language	English
Pages (from-to)	2544-2550
Number of pages	7
Journal	Chemistry of Materials
Volume	19
Issue number	10
DOIs	https://doi.org/10.1021/cm062675s
State	Published - 15 May 2007
Externally published	Yes

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@article{463ef7d6584247fdb2d2bee70fa8d7d9,

title = "Novel ionic liquid crystals based on N-alkylcaprolactam as cations",

abstract = "A novel series of ionic liquids (ILs) based on N-alkyl-ε-caprolactam as cations [Cn-CP]+ (Cn = alkyl with different numbers of C atoms; n -6, 8, 10, 12, 16, or 18) containing toluene-p-sulfonate [TS]- and methanesulfonate [MS]- as anions have been synthesized via a one-step atom-economic reaction. Characterizations of these ILs by differential scanning calorimetry, polarizing optical microscopy, variabletemperature powder X-ray diffraction, etc., were conducted. The results showed that the caprolactambased ILs (n ≥ 8) were enantiotropic thermotropic liquid crystals, except for C18-CPMS (monotropic), and displayed smectic A phases. Some properties, such as higher transition enthalpies (e.g., ΔH = 83.1 kJ/mol for C18-CPTS), higher specific heat capacities (e.g., Cp = 2.85 J/g·K for C16-CPTS) and higher heat storage densities (e.g., sensible heat storage density Es = 262.81 MJ/m3 for C16\textasciitilde{}CPTS; latent heat storage density E1 -146.0 MJ/m3 for C18-CRTS), were observed. Fluorescence measurements showed that the homologous Cn-CPTS ILs exhibited strong fluorescence behavior. Finally, the test of acute toxicity toward rats showed that these new ILs were less toxic than the popular [BMIm]BF4 IL.",

author = "Jing Yang and Qinghua Zhang and Laiying Zhu and Shiguo Zhang and Jian Li and Xiaoping Zhang and Youquan Deng",

year = "2007",

month = may,

day = "15",

doi = "10.1021/cm062675s",

language = "英语",

volume = "19",

pages = "2544--2550",

journal = "Chemistry of Materials",

issn = "0897-4756",

publisher = "American Chemical Society",

number = "10",

}

TY - JOUR

T1 - Novel ionic liquid crystals based on N-alkylcaprolactam as cations

AU - Yang, Jing

AU - Zhang, Qinghua

AU - Zhu, Laiying

AU - Zhang, Shiguo

AU - Li, Jian

AU - Zhang, Xiaoping

AU - Deng, Youquan

PY - 2007/5/15

Y1 - 2007/5/15

N2 - A novel series of ionic liquids (ILs) based on N-alkyl-ε-caprolactam as cations [Cn-CP]+ (Cn = alkyl with different numbers of C atoms; n -6, 8, 10, 12, 16, or 18) containing toluene-p-sulfonate [TS]- and methanesulfonate [MS]- as anions have been synthesized via a one-step atom-economic reaction. Characterizations of these ILs by differential scanning calorimetry, polarizing optical microscopy, variabletemperature powder X-ray diffraction, etc., were conducted. The results showed that the caprolactambased ILs (n ≥ 8) were enantiotropic thermotropic liquid crystals, except for C18-CPMS (monotropic), and displayed smectic A phases. Some properties, such as higher transition enthalpies (e.g., ΔH = 83.1 kJ/mol for C18-CPTS), higher specific heat capacities (e.g., Cp = 2.85 J/g·K for C16-CPTS) and higher heat storage densities (e.g., sensible heat storage density Es = 262.81 MJ/m3 for C16~CPTS; latent heat storage density E1 -146.0 MJ/m3 for C18-CRTS), were observed. Fluorescence measurements showed that the homologous Cn-CPTS ILs exhibited strong fluorescence behavior. Finally, the test of acute toxicity toward rats showed that these new ILs were less toxic than the popular [BMIm]BF4 IL.

AB - A novel series of ionic liquids (ILs) based on N-alkyl-ε-caprolactam as cations [Cn-CP]+ (Cn = alkyl with different numbers of C atoms; n -6, 8, 10, 12, 16, or 18) containing toluene-p-sulfonate [TS]- and methanesulfonate [MS]- as anions have been synthesized via a one-step atom-economic reaction. Characterizations of these ILs by differential scanning calorimetry, polarizing optical microscopy, variabletemperature powder X-ray diffraction, etc., were conducted. The results showed that the caprolactambased ILs (n ≥ 8) were enantiotropic thermotropic liquid crystals, except for C18-CPMS (monotropic), and displayed smectic A phases. Some properties, such as higher transition enthalpies (e.g., ΔH = 83.1 kJ/mol for C18-CPTS), higher specific heat capacities (e.g., Cp = 2.85 J/g·K for C16-CPTS) and higher heat storage densities (e.g., sensible heat storage density Es = 262.81 MJ/m3 for C16~CPTS; latent heat storage density E1 -146.0 MJ/m3 for C18-CRTS), were observed. Fluorescence measurements showed that the homologous Cn-CPTS ILs exhibited strong fluorescence behavior. Finally, the test of acute toxicity toward rats showed that these new ILs were less toxic than the popular [BMIm]BF4 IL.

UR - https://www.scopus.com/pages/publications/34249713257

U2 - 10.1021/cm062675s

DO - 10.1021/cm062675s

M3 - 文章

AN - SCOPUS:34249713257

SN - 0897-4756

VL - 19

SP - 2544

EP - 2550

JO - Chemistry of Materials

JF - Chemistry of Materials

IS - 10

ER -

Novel ionic liquid crystals based on N-alkylcaprolactam as cations

Abstract

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