The title lead(II) derivative was obtained as dark blue crystals by treatment of PbCl2 with (TMEDA = N,N,N‘,N‘-tetramethylethylenediamine) in tetrahydrofuran and its structure determined by X-ray diffraction. The compound is in effect the first dialkylead(II) species to be structurally characterized. The C−Pb−C angle is 117.1(2)°. Analogous treatment of SnCl2 yielded a yellow solid, which was judged from spectroscopic data to be the TMEDA complex of the analogous stannacycloalkane.

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This review focuses on recent developments in the chemistry of side chain liquid crystal polymers. It concentrates on current trends in synthetic methods and novel, well defined structures, supramolecular arrangements, properties, and applications. The review covers literature published in this century, apart from some areas, such as dendritic and elastomeric systems, which have been recently reviewed.

Side chain polysiloxane with 5-(pentyloxy)-3-methyloxy-9,10,16,17,23,24-hexakis(octenyloxy)phthalocyanine moieties is synthesized by hydrosilylation reaction. The phase behavior and thermooptical properties of the polysiloxane and starting 2-(pent-4-enyloxy)-3-methyloxy-9,10,16,17,23,24-hexakis(octenyloxy)phthalocyanine is examined by POM (Polarizing optical microscopy), TOA (thermooptical analysis), DSC (differential scanning calorimetry), AFM (atomic force microscopy) and SAXS (small angle X-ray scattering) studies. The effect of the attachment of phthalocyanine to polysiloxane chains over phase transitions and phase morphology is discussed in details

A series of novel side chain polymers-silylated polyethylenes were prepared containing 4′-methoxyphenyl-4-(ω-alkenyloxy)benzoate mesogenic groups of the general formula {-CH2-CH[SiMe2-(CH2)mOC6H4C(O)OC6H4OMe]}n-, where m ) 4, 5, 8, 11. The ones having five and eight carbon atoms in the alkane moiety of a flexible spacer proved to be liquid crystalline, independent of molecular weight (DP ) 75, 230). Alternative synthetic pathways have been described starting with anionic polymerization of Me3SiVi or Me2PhSiVi in the presence of BuLi, followed by functionalization of side silyl group to give reactive Si-H bonds and hydrosilylation of terminal, mesogenic alkenes. The properties of liquid crystal polyethylenes were compared with those of side chain polycarbosilanes of similar structure. The advantage of polyethylenes, while preserving all important features of polycarbosilanes, is shown by their broad temperature range of mesophase formation and the economically attractive synthesis.

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A new method of paper hydrophobization was evaluated based on a coating agent containing a water emulsion of triethoxymethylsilane with standard starch solutions. The effects of different concentrations on the hydrophobic properties of the resulting silicone-coated materials were investigated using a penetration dynamics analyzer (PDA) and water contact angle measurements. This study also examined the effects of the applied coatings on the paper’s tensile strength, tear index, roughness, air permeance, and ISO brightness. Preliminary studies were conducted on the molecular interaction mechanisms between the silicone agent and starch modifiers, based on solid state nuclear magnetic resonance (NMR) and scanning electron microscope (SEM) images.

BACKGROUND: Due to their wide variety of applicable substituents and relative ease of synthesis, liquid crystalline polymers are extensively studied as stationary phases in gas–liquid chromatography (GC). Although side‐chain liquid crystalline polycarbosilanes, due to their higher thermal and chemical stability compared to polysiloxanes, seem to be natural candidates for GC stationary phases, they have not yet been tested for such applications. RESULTS: Five stationary phases for GC, based on liquid crystalline polycarbosilanes and polysiloxanes, capable of generating nematic, smectic and condis mesophases were studied. HETP values and Kováts retention indices were calculated, using a series of probes (linear alkenes, benzene, xylene, toluene, cumene, mesitylene), and compared with those obtained for a typical stationary phase based on polydimethylsiloxane (OV‐101). The separation abilities of polycarbosilanes and poly(di‐n‐butylsiloxane) were evaluated using inverse gas chromatography. CONCLUSION: The results suggest that polycarbosilane‐based phases have similar separation properties to those of polysiloxane liquid crystals with some advantages such as higher thermal and chemical stability and good, linear dependence of retention times on temperature. The poly(di‐n‐butylsiloxane)‐based phase did not exhibit any advantages over the typical OV‐101 phase. Copyright © 2009 Society of Chemical Industry