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This dissertation focusses on the synthesis of more advanced polymer structures by the use of air-stable Ni-initiators and the strong control over the Kumada catalyst transfer polycondensation (KCTP). About a decade ago a controlled chain-growth polymerization of poly(3-alkylthiophene) (P3AT) was published, which opened possibilities for the formation of new polymeric structures. Different research groups have focused on end-functionalization of conjugated polymers (CPs) in different ways. Up to this point, the variety of functionalization is rather limited and polymer samples often show unfunctionalized or unwanted difunctionalized polymers. With the implementation of an air-stable Ni-initiator, functional groups are introduced at the start of a polymer chain. In this way, together with the strong control over polymerization, well-defined polymers can be obtained.In the first part, a generic protocol for the end-functionalization of poly(3-hexylthiophene) (P3HT) and the formation of different kind of organic/inorganic hybrid materials is developed. P3HTs are end-functionalized with a phosphonic ester, pyridine, protected thiol and protected phenol groups using corresponding functionalized air-stable Ni-initiators. The protected thiol and phenol functionalized P3HTs are converted in thiol and phenol functionalized P3HTs by means of quantitative post-polymerization reactions. These functional end-groups are used to prepare hybrid materials from a broad variety of nanoparticles (NPs), including metal oxides, quantum dots and noble metals.From this broad range of hybrid materials, P3HT/Au is considered a good candidate for further investigation. Starting from the P3HT/Au hybrid, other protected thiol functionalized initiators are synthesized, which are used to polymerize and end-functionalize P3HTs in which the length of the linker between the thiol and the P3HT chain is varied. The protected thiol P3HTs are in situ deprotected and anchored onto Au NPs to form P3HT/Au hybrids. The influence of the length of the linker between the P3HT and the Au NP surface on the fluorescence is investigated. The strongest quenching is observed for the shortest linkers. Also a protected thiol poly(3-octylselenophene) (P3OS) is polymerized and anchored together and separately with P3HT to an Au NP. The presence of P3OS results in an additional quenching when P3OS is anchored on the same NP as P3HT.Besides linking organic to inorganic material, these functional groups can also be employed to link two P3AT blocks together, not by means of a covalent bond, but by multiple hydrogen bonds (MHBs). In this research 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 are synthesized using a functionalized Ni-initiator. By a series of post-polymerization reactions, including click chemistry, a H-donor and -acceptor entity are attached to the end of the polymer chains. Chiral side chains are 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 CD spectroscopy.In the part above, chiral entities are represented in one of both blocks. In the final part, we demonstrate that chirality can also be expressed in a polymer molecule that does not contain any excess of chiral centers; in this specific material the chirality is evoked by a specific order of manipulations (‘events’). The polymer studied is an AB all-conjugated block copoly(3-alkylthiophene) which makes use of an o-tolyl initiator to prevent any BAB contamination. The first block of this all-conjugated block copolymer contains exactly the same amount of (S)-enantiomers as the second block (R)-enantiomers. Exploiting the difference in solubility of both blocks, a chiral response is evoked from this polymer without the need of a chiral trigger.