Novel bolaamphiphiles, consisting of a biphenyl rigid core, polar 2,3-dihydroxypropoxy groups at each terminal end, and an additional long alkyl chain in a lateral position have been synthesized. The structures of these ternary block molecules were systematically changed by variation of the length and position of the alkyl chain, by introduction of additional spacer units between one of the 2,3-dihydroxypropyl groups and the rigid core, and by replacement of one of the 2,3-dihydroxypropoxy groups by a single hydroxy group. The influence of these structural variations on the liquid crystalline properties of these new materials was investigated by polarized-light microscopy, differential scanning calorimetry, and X-ray diffraction. These investigation have shown that, by elongation of the lateral chain, a transition from a smectic monolayer structure (SmA 1 ) via a strongly distorted layer structure (SmA + ), a centered rectangular columnar phase (Col r /c2mm) and a noncentered rectangular columnar phase (Col r /p2gg) to a hexagonal columnar phase (Col h /p6mm) takes place. Elongation of the bolaamphiphilic core leads to the loss of the columnar phases, which are replaced by smectic phases, whereas reduction of its length favors the hexagonal columnar phase. This phase sequence is explained as a result of the microsegregation of the lateral alkyl chains from the rigid aromatic cores. The segregated alkyl chains are organized in columns that interrupt the smectic layers. The hydrogen bonding keep the bolaamphiphilic cores fixed end to end, so that they form networks of cylinders around the lipophilic columns. The space required by the alkyl chains with respect to the length of the bolaamphiphilic cores is restricted and largely determines the geometry of the cylinders, which leads to the observed phase sequence. The obtained mesophase morphologies, built up by three distinct sets of subspaces, are related to morphologies of some ternary block copolymers. Furthermore, the investigated compounds represent a novel class of materials, capable of forming supramolecular columnar mesophases.

To date the manufacturing of ionic liquids on a large scale is limited by ineffective batch procedures employed for the alkylation step. Here we present a way to intensify the synthesis of 1-butyl-3-methylimidazolium bromide ([BMIM]Br) by using a continuously operating microreactor system. It consists of a microstructured mixer of 450 mm channel width and reaction tubes with inner diameter ranging from 2 to 6 mm allowing a production rate of 9.3 kg [BMIM]Br per day. In this reactor system the strongly exothermic alkylation can be thermally controlled even at elevated temperatures leading to high reaction rates in a solvent-free modus. Inspite of temperatures up to 85 uC the product purity achieved was above 99%. The degree of process intensification achieved results in a more than twentyfold increase of the space-time-yield compared to a conventional batch process. The measured conversion data could be modelled successfully using a second order reaction kinetic. With the generated kinetic parameters the time course of temperature and conversion was also simulated for batch synthesis. Based on these data the performance of the continuous micro-reactor and the conventional batch process was compared. The simulation shows the potential of process intensification as an improvement of space-time-yield in the range of two orders of magnitude. Materials and methodsAs a representative of the reactions of interest, the butylation of methylimidazole, an example of a strongly exothermic

A series of bis(trifluoromethylsulfonyl)imide ionic liquids (ILs) with classical as well as mildly functionalized cations was prepared and their viscosities and conductivities were determined as a function of the temperature. Both were analyzed with respect to Arrhenius, Litovitz and Vogel-Fulcher-Tammann (VFT) behaviors, as well as in the context of their molecular volume (V(m)). Their viscosity and conductivity are highly correlated with V(m)/T or related expressions (R(2) ≥0.94). With the knowledge of V(m) of new cations, these correlations allow the temperature-dependent prediction of the viscosity and conductivity of hitherto unknown, non- or mildly functionalized ILs with low error bars (0.05 and 0.04 log units, respectively). The influence of the cation structure and mild functionalization on the physical properties was studied with systematically altered cations, in which V(m) remained similar. The T(o) parameter obtained from the VFT fits was compared to the experimental glass temperature (T(g)) and the T(g)/T(o) ratio for each IL was calculated using both experimental values and Angell's relationship. With Walden plots we investigated the IL ionicity and interpreted it in relation to the cation effects on the physical IL properties. We checked the validity of these V(m)/T relations by also including the recently published variable temperature viscosity and conductivity data of the [Al(OR(F))(4)](-) ILs with R(F) =C(H)(CF(3))(2) (error bars for the prediction: 0.09 and 0.10 log units, respectively).

Rigid bolaamphiphiles with lateral alkyl chains such as 1 form columnar mesophases of a novel type based on microsegregation of the three incompatible parts of the molecules (shown schematically).

Rodlike amphiphilic molecules that contain exclusively aromatic building-blocks and no flexible alkyl chains have been synthesized and their mesomorphic properties investigated. These novel compounds bear diol head groups of different size (2,3-dihydroxypropyloxy or 5,6-dihydroxy-3-oxahexyloxy groups) at one end of a biphenyl unit, various aromatic segments (benzyloxy, 4-, 3-, or 2-methylbenzyloxy, phenoxy groups) at the other, and additional methyl substituents in different positions. They were synthesized by using Suzuki cross-coupling reactions as the key steps. Their thermotropic mesomorphism was investigated by means of polarized light optical microscopy, differential scanning calorimetry, and, for enantiotropic phases, by X-ray scattering. The liquid crystallinity of this class of compounds is influenced by protic solvents, such as water and glycerol. Dependent on the temperature and the solvent content, different SA phases were found. Several mesophases resulting from the frustration of these layer structures (e.g., different columnar phases, optical isotropic mesophases, and nematic phases) were also present. The smectic phases have different degrees of intercalation (SAd, SA2). The columnar phases are supposed to be ribbon structures that result from the collapse of the smectic layers. They occur in some pure compounds or they are induced upon the addition of protic solvents. The particular phase sequences of the different compounds depend mainly on the position of the methyl substituents at the biphenyl cores and are largely determined by the degree of intercalation of the aromatic cores.

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Rigide Bolaamphiphile mit lateralen Alkylketten wie 1 können, als Folge der Mikrosegregation der drei in diesen Molekülen verknüpften, aber miteinander unverträglichen Molekülteile (schematisch dargestellt), columnare Mesophasen ungewöhnlicher Struktur bilden.