National Interest Co-Financed Research Projects ("PRIN"). Year 2003 (duration 2004-2005)

Title: Liquid crystals and macromolecules for nano-organised structures

Research Units

Unità Afferenti e Responsabili di Unità

1. Politecnico di Milano, Dip. di Chimica, Materiali e Ingegneria Chimica "G. Natta" (Prof. G. Allegra)
2. Università di Napoli, Dip. di Chimica (Prof. V. Barone)
3. Università della Calabria (Prof. G. Chidichimo)
4. Università di Bologna (Prof. G. Gottarelli)
5. Università di Catania (Prof. D. M. Grasso)
6. Università di Padova (Prof. G. Moro)
7. Università di Pisa (Prof. C.A. Veracini)
8. Università di Bologna (Prof. C. Zannoni)

Abstract of Research Programme

The general objective of this programme is to contribute to the understanding of the mechanisms leading to the building up and control of ordered molecular organizations from the nanoscale level. We shall combine strong expertise in liquid crystals and macromolecules to tackle systems of increasing complexity and to actually prepare and characterize some of these organized
systems. Various of the materials we wish to consider, e.g. better anisotropic polymers, novel bulk ferroelectric nematic phases, chiral ferro or anti ferroelectric smectics, photoresponsive elastomers, molecular ribbon phases can only be prepared or improved by a better understanding of the essential molecular features contained in their building blocks. We shall use the knowledge obtained to improve applications of technological interest, e.g. direct and reverse mode polymer dispersed liquid crystals (PDLC) for electro-optic applications. We also intend to apply the methods developed to tackle some problems of biological interest, e.g. the effects of anisotropic environment and of adsorption on ordering and folding of some proteins.
We shall rely on the variety of methodologies: advanced quantum chemical modeling, atomistic and coarse grained Monte Carlo and Molecular Dynamics computer simulations, synthesis, nanocalorimetry, SAXS, WAXS and spectroscopic methods ranging from magnetic resonance techniques (NMR, ESR) to fluorescence, CD, available to our teams, and on the expertise and coordination levelthat the participating teams have developed collaborating liquid crystal systems, in particular with the support, in the last five years, of three previous PRIN grants. In these successful biennial projects (78 papers published on international journals in the first, 84 in the second and 48 in the first year of the third) we have been concerned with simpler liquid crystals. Here we intend to base on that work and move towards more complex and macromolecular systems. We have thus involved some leading polymer groups with experience in theory, modelling, characterization and synthesis to complement our expertise. We believe that advances in building nano-organized materials will involve advances in modelling and simulations, in particular moving towards computational tools with predictive capabilities. We have thus now included a leading group in quantum chemistry and DFT, also with the intent to develop better potentials and models for atomistic computer simulations. At the same time we shall continue to improve molecular level models on one hand adding details (arbitrary shape, charge distributions, flexibility, chirality) and on the other extending them to deal (at a level of complex beads and spring approach) with anisotropic polymers and with nanoconfined environments with
complex surfaces. Static and dynamic properties will be considered, including rheological ones. We shall then deal with systems that go from nematics to molecular materials and some systems of technological (PDLC, Polymers, Liquid Crystal Elastomers, Filled Nematics, Microemulsions) and of biological (Proteins, Model Membranes) interest.