In a first part of this article, the synthesis of AB type block copoly(3-alkylthiophene)s initiated by Ni(dppp)Cl 2 , the most commonly used initiator for these polymers, is investigated. For this study the respective 1 H NMR resonances of all possible end-groups are identified. This result confirms the hypothesis that the Ni(dppp) species can walk back to the beginning of the polymer chain and that propagation can occur at both chain ends. The next part of the article studies the chiroptical behavior of AB-type block copoly(3-alkylthiophene)s with one chiral block and compares the results with those of the corresponding random copolymers. In order to obtain exclusively AB-type block copolymers, the polymers were prepared from a modified Ni initiator. They all have the same degree of polymerization but vary in the length of the respective blocks. The chiroptical behavior was studied by changing the ratio solvent/nonsolvent, meanwhile monitoring the UVÀvis and circular dichroism (CD) spectra. Three series were investigated: one in which both blocks aggregate simultaneously, one in which the achiral block stacks before the chiral block, and one in which the chiral block stacks first followed by the achiral block. It was found that when the blocks stack independently, the (chiral/achiral) stacking of the latter is significantly influenced by the former. If both blocks of the polymer chains aggregate simultaneously, Cotton effects which are significantly larger than those of the chiral homopolymer are found.

Poly(3-hexylthiophene)s were synthesized with phosphonic ester, pyridine, thiol and phenol endgroups using functionalized air-stable Ni-initiators. The protected thiol and phenol functionalized P3HTs were converted in thiol-and phenol P3HTs by quantitative postpolymerization reactions.2 1 H NMR and MALDI-ToF analysis showed very high degrees of functionalization and strong control over the polymerization except for the pyridine functionalized P3HT. These functional end-groups were used to prepare hybrid materials from a broad variety of nanoparticles, including metal oxides, quantum dots and noble metals.

No abstract

Regioregular poly(3-hexylthiophene)s with chain lengths varying from 5 to 100 monomers are synthesized. Poly(3-hexylthiophene)s show in solution an unexpectedly significant second-order nonlinear optical response. The increase in transition dipole moment upon oligomerisation causes the significant second-order nonlinear optical response.

The synthesis of a block copoly(3-alkylthiophene) consisting of two different P3AT blocks equipped with an H-donor and -acceptor functionality is presented. The P3ATs were synthesized using a functionalized Ni-initiator. By a series of postpolymerization reactions, including click chemistry, a H-donor and -acceptor entity were attached to the end of the polymer chains. Evidences for a quantitative functionalization of the polymers were provided by 1 H NMR and MALDI-ToF analyses. Chiral side chains were implemented on one of both blocks, allowing the study of the influence of the H-bond formation on the chiral self-assembly using UV-vis and circular dichroism (CD) spectroscopy.