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This work focuses on the synthesis and characterisation of a new class of materials so-called organic-inorganic hybrid polymers, whose main characteristics are the synergy and bonding between an organic phase with an inorganic phase. This thesis is a research effort towards getting new and better materials for diverse and specialised applications.The synthesis of materials was carried out in two stages: in the first one hybrid particles of SiO2 and TiO2 were obtained via sol-gel process, both of them functionalised with vinyl groups, and nominal diameters of 200 nm and 220 nm, respectively. In the second stage hybrid polymers of the type polystryrene-SiO2 (PS-SiO2) and polystyrene-TiO2 (PS-TiO2) were obtained via free radical polymerisation, and employing different concentrations of the functionalised hybrid particles obtained in the first stage. These materials formed translucent and semiflexible films.The presence of the inorganic phase inside the organic phase for both systems, PS-SiO2 and PS-TiO2, promoted a decrease on the Tg inversely proportional to the concentration increase of PS-SiO2 and PS-TiO2, respectively, which suggests that the particles confer a plasticiser effect over the polymer matrix.For both systems, PS-SiO2 and PS-TiO2, apart from the Tg decrease, there were differences on the elastic modulus measured. These results suggest that these differences might be due to the difference in particle size and chemical species. Likewise, the thermal stability of both PS-SiO2 and PS-TiO2 increased significantly and in the same order, relative to pristine polystyrene.

Polytriarylamine copolymers can be prepared bySuzuki-Miyaura cross-coupling reactions of bis N-methyliminodiaceticacid (MIDA) boronate ester substituted arylamineswith dibromo arenes. The roles of solvent composition, temperature,reaction time, and co-monomer structure were examinedand (co)polymers prepared containing 9, 9-dioctylfluorene(F8), 4-sec-butyl or 4-octylphenyl diphenyl amine, and N, N0-bis(4-octylphenyl)-N, N0-diphenyl phenylenediamine units,using Pd(OAc)2/2-dicyclohexylphosphino-20,60-dimethoxybiphenyl (SPhos) catalyst system. The performance of a difunctionalized MIDA boronate ester monomer was comparedwith that of an equivalent pinacol boronate ester. Higher molarmass polymers were produced from reactions starting with adifunctionalized pinacol boronate ester monomer than theequivalent difunctionalized MIDA boronate ester monomer inbiphase solvent mixtures (toluene/dioxane/water). Matrixassistedlaser desorption/ionization mass spectroscopic analysisrevealed that polymeric structures rich in residues associatedwith the starting MIDA monomer were present,suggesting that homo-coupling of the boronate ester must beoccurring to the detriment of cross-coupling in the step-growthpolymerization. However, when comparable reactions of thetwo boronate monomers with a dibromo fluorene monomerwere completed in a single phase solvent mixture (dioxane1water), high molar mass polymers with relatively narrow distribution ranges were obtained after only 4 h of reaction

As key components of flexible organic electronics, the synthesis ofpolythiophenes via less toxic and more cost-effective routes is demanded. Anefficient synthetic route for the production of thienyl-containing homopolymers andcopolymers has been developed.The synthetic approach consists of: i) the synthesis in high yield and highpurity of thienyl borane monomers protected with N-methyliminodiacetic acid(MIDA) via C-H electrophilic borylation. This reaction uses a combination ofinexpensive reagents BCl3, AlCl3, and 2,6-dichloropyridine (Cl2Py) for theregioselective electrophilic aromatic substitution of thiophenes, followed by additionof a second aprotic amine pre-esterification to reduce the Brønsted acidity of thereaction mixture. In situ esterification provided the desired thienyl MIDA boronateester monomers in one-pot at room temperature. ii) Subsequent Suzuki-Miyaurapolymerisation of the synthesised monomers to produce well defined thienylcontainingπ-conjugated polymers in high molecular weight and high yields.Key reaction parameters for successful Suzuki-Miyaura polymerisation ofthienyl-derived MIDA boronate esters under mild temperatures (i.e., 55 °C in THF)were found: a) an optimal monomer:H2O:base ratio, which enables controlledhydrolysis of the BMIDA moiety into its corresponding boronic acid at appropriaterates for high fidelity polymerisation. b) Nature of the base, where K3PO4 providedthe best results for production of homopolymers (e.g., rr-P3HT), or KOH whichgave excellent results for the formation of copolymers across a range ofelectronically different comonomers (e.g., pCPDT-BT). Thus, it is demonstrated thatthe approach is a general strategy for the highly efficient production of thienylcontainingπ-conjugated regioregular, regiosymmetric and Donor-Acceptorpolymers.

The synthesis of highly regioregular poly(3-hexylthiophene-2,5-diyl), rr-P3HT, by Suzuki–Miyaura polymerization is reported. The key N-methyliminodiacetic acid (MIDA) boronate ester thienyl monomer was synthesized using a one-pot multigram scale procedure, in high purity, and in good isolated yield (80%) by direct electrophilic borylation. Conditions for the hydrolysis of the MIDA protecting group and the polymerization reaction were investigated. The optimal procedure gave rr-P3HT with >98% HT couplings, excellent isolated yields (up to 94%), and polymer molecular weights up to Mn = 18.7 kDa and Mw = 42.7 kDa. The performance of the MIDA containing monomer was compared to that of the pinacol boronate ester under identical polymerization conditions, with the latter producing lower molecular weight polymers in reduced yield.