*Liquid Crystals and Display Technology*

diffraction efficiency of POLICRYPS gratings. Journal of the Optical Society of America B: Optical Physics. 2005;**22**: 735-742

[171] Coates D. Polymer dispersed liquid crystals. Journal of Materials Chemistry. 1995;**5**:2063-2072

[172] Liu Y, Zheng J, Shen T, Wang K, Zhuang S. Diffusion kinetics investigations of nano Ag-doped holographic polymer dispersed liquid crystal gratings. Liquid Crystals. 2019; **46**:1050-1059

**79**

**1. Introduction**

**Chapter 3**

Vectors

**Abstract**

by <sup>1</sup>

Cholesteric Liquid Crystal

Polyesteramides: Non-Viral

*Mercedes Pérez Méndez and José Fayos Alcañiz*

H and 13C-NMR, COSY and HSQC, exhibiting two 1

liquid crystal polyesters have also been synthesized in our laboratory.

characterization, SAXS/WAXS, molecular simulation

**Keywords:** cholesteric LC polymer, biocompatible polyesteramides, synthesis,

In 1944, Erwin Schrödinger, one of the founders of quantum mechanics, completed in Dublin a small book entitled *What Is Life? The Physical Aspect of the Living Cell* [1]. He predicted there the concept of "aperiodic crystal", to define a gene or perhaps the whole fibre of the chromosome, "that in my opinion, is the material

Polyesteramides PNOBDME (C34H38N2O6)n, Poly[oxy(1,2-dodecane)-oxycarbonyl-1,4-phenylene-amine-carbonyl-1,4-phenylene-carbonyl-amine-1,4 phenylene-carbonyl], and PNOBEE (C26H22N2O6)n, Poly[oxy(1,2-butylene) oxy-carbonyl-1,4-phenylene-amine-carbonyl-1,4-phenylene-carbonyl-amine-1,4-phenylene-carbonyl], have been designed and synthesized as cholesteric liquid crystals (LCs)—through a condensation reaction between 4- 4′-(terephthaloyldiaminedibenzoic chloride) (NOBC) and racemic glycol, DL-1,2-dodecanediol or DL-1,2-butanediol, respectively—as chemical modifications of multifunctional cholesteric LC polyesters, involving new properties but holding the precursor helical macromolecular structures. The new compounds have been characterized

signals observed for each enantiomer, attributed to two diastereomeric conformers, *gg* and *gt*, of the torsion containing the asymmetric carbon atom in the spacer. They have also been characterized by x-ray diffraction with synchrotron radiation source. Thermal behaviour of the new compounds is studied by thermogravimetric (TG) and differential scanning calorimetry (DSC) analysis. The substitution of the ester groups in the mesogen by amide groups causes an increase of thermal stability with respect to the precursors. Optical rotatory dispersion (ORD) is evaluated. Morphology of powdered PNOBDME exhibits spherical clusters of about 5 μm in diameter homogeneously dispersed. Molecular models show helical polymeric chains with stereoregular head-tail, isotactic structure, explained as due to the higher reactivity of the primary hydroxyl with respect to the secondary one in the glycol through the polycondensation reaction. Besides being biocompatible, these synthetic polyesteramides have proved to act as non-viral vectors in gene therapy and be able to transfect DNA to the nucleus cell. Similar new cationic cholesteric

H-independent sets of
