| Abstract [eng] |
Dendrimers are multivalent, well-defined materials that constitute a new class of polymer macromolecules. They have been extensively studied over the past several decades mainly due to their exceptional structure properties. The size of molecule, number of terminal groups, molecular weight and several other properties of dendrimers could be precisely controlled during synthesis. The main goal of this thesis is to investigate the optical properties and light induced photochemical reaction dynamics within the PPI and PAMAM dendrimers functionalized by CAzPA and ESA type terminal groups by means of several spectroscopic techniques. Because photochromism of CAzPA and ESA type terminal groups is associated with light induced isomerization and tautomerization photochemical reactions, the main attention of present thesis was devoted to investigate dynamical properties of functionalized dendrimers as an influence of dendrimer type and its generation. Investigations of dynamic properties of PPI and PAMAM dendrimers functionalized with the CAzPA terminal groups have shown that isomerization rate is insensitive to dendrimer type, solvent and excitation wavelength. The isomerization rate of the dendrimer films take place in about 15 ps and it is only seven times slower than in dendrimer solvent. Both experimental and theoretical optical studies performed on PPI dendrimers functionalized with the ESA type terminal groups reveal four stable tautomeric forms with different energy in the ground state. Transient absorption investigations also reveal that relative concentrations of different tautomeric forms depend on the dendrimer generation. |
