Bithiophenesilane-Based Dendronized Polymers: Facile Synthesis and Properties of Novel Highly Branched Organosilicon Macromolecular Structures

Abstract

The synthesis of two novel bithiophenesilane-based dendronized polymers by a chain growth Kumada polymerization, their molecular properties in dilute solutions and thermal properties in the bulk are described and compared with those of bithiophenesilane dendrimers. GPC equipped with a dual light scattering detector has shown that the polymers exhibit narrow polydispersity indices (PDI = 1.22–1.23) and have a weight-average polymerization degree of 44 for P1 and 30 for P2, which correspond to 88 and 120 bithiophenesilane fragments, respectively. Spectral-luminescent investigations showed that both polymers among with the bithiophenesilanes contain from 1 to 4 terthiophenesilane fragments in every macromolecule, which leads to the so-called “dendritic molecular antenna” effect. The intramolecular energy transfer efficiency was measured to be 50 and 70% for polymers P1 and P2 respectively, which, alongside with the results of viscometric studies, points out to the compact conformation of these macromolecules in solution, which is close to those of bithiophenesilane dendrimers.

Effects of oligothiophene π-bridge length on physical and photovoltaic properties of star-shaped molecules for bulk heterojunction solar cells

“…From the value of the onset reduction potentials (4 red ) and the onset oxidation potentials (4 ox ), the LUMO and HOMO energy levels of these molecules were calculated as shown in Table 2, according to the equations of LUMO ¼ Àe(4 red + 4.40) (eV) and HOMO ¼ Àe(4 ox + 4.40) (eV). 34 The LUMO energy levels were determined to be À3.46 eV for N(Ph-1T-DCN-Me) 3 , À3.41 eV for N(Ph-2T-DCN-Me) 3 , À3.41 eV for N(Ph-2T-DCN-Hex) 3 , and À3.40 eV for N(Ph-3T-DCNHex) 3 by the above-mentioned equation, revealed that the 3 , N(Ph-2T-DCN-Me) 3 , N(Ph-2T-DCN-Hex) 3 , and N(Ph-3T-DCN-Hex) 3 in ODCB solution (a) and in the film (b).…”

Achievements in polycondensation and condensation polymers

“…Organosilicon dendrimers containing aromatic and heterocyclic fragments, benzothiadiazole, anthracene, thienyl, oxazole, fluorene, and thiophene, as well as liq uid crystalline dendrimers, were synthesized and char acterized [212,213,[217][218][219][220][221][222][223].…”

Development of new methods in modern selective organic synthesis: preparation of functionalized molecules with atomic precision

“…722 The narrow molecular-mass distribution (1.22 ± 1.23), high molecular masses and the use of nickel catalyst indi-cate that the process follows a living polymerization mechanism. Thus, it was demonstrated that bulky monomers can also be polymerized by this mechanism.…”