Copper lamellar phases

Figure 15. Schematic representation of the structure of the lamellar phase of the copper complex 11, with R=C12H25, proposed by Sakashita et al. [44]. (Reproduced by permission of Gordon and Breach).

The annelides form mesogenic copper complexes, 78. The lamellar phases, intermediate between crystalline solids and liquid crystals, have been termed tegma crystals [ 183]. 

I ig. 5.8 (a) A triple lamellar ternary eutectic in the system cadmium dy-tin Ui)-lead (y). The lamellar arrangement is ay0yy.y (Kerret al.20), (b)The complex ternary eutectic in the aluminium-copper-magnesiiim system. The lamellar phases are aluminium and CuAh and thefibrous phase is Mg-rich (Cooksey ctndHellawelTtt-). 

It has been shown that a j8-diketonate liquid crystal containing palladium(II) and oxo-vanadium(IV), analogous to known copper complexes (which display discotic lamellar and columnar mesophases), has been prepared and characterized palladium complexes are mesomorphic but their identification is difficult due to their decomposition in the isotropic phase the complex n = 10 seems to present a Nj phase on the basis of optical microscopy. The vanadium complexes are enantiotropic discotic [75], while the vanadium complex, 30, presented by Styring et al. [76] (n= 10), exhibited a short monotropic columnar discotic phase. 

C-E-based block copolymers (see Eig. 18.18) [48]. When the second phase is lamellar, chain architecture plays a major role. Diblock copolymers show very small strain (brittle) all the films fail at 2% and deforms predominantly by crazing. In contrast, triblock and pentablock copolymers show ductility and toughness (no failure up to 27%, an upper limit of a copper grid method) and the deformation mode is mainly shear deformation, as explained above. 

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