This project was focused on the synthesis of novel Polymers of Intrinsic Microporosity (PIMs) that are soluble in common low boiling point solvents so that self-standing films can be prepared for gas permeability measurements. The common building unit of these novel PIMs was triptycene and its derivatives. Modification of these triptycene compounds enabled the alteration of the polymeric backbone, so that we could tune the gas permeability properties. Modifications included the substitution of different functional groups (e.g. addition of methyl groups) and also the extension via benzoannulation of the triptycene structure. The synthesis of the PIMs was based around three different polymerisation techniques. The first one involved the formation of triptycene-based polyimides (PIs) using a triptycene based dianhydride, prepared in a multistep synthesis. Shorter and cheaper synthetic routes were attempted, but all to no avail. The resulting triptycene monomer was reacted with a variety of commercial and non-commercial bisanilines for the formation of several PIM-PIs, all exhibiting different performances. Robust self-standing films were obtained for two of these PIM polyimides. In addition to the formation of polyimides, the synthesis of Tröger’s Base (TB) polymers, also based on triptycene components, were achieved. This type of polymerisation involves the reaction between a “bisaniline” monomer and a source of “formaldehyde”, such as dimethoxymethane (DMM), in a strong acid media, typically trifluoroacetic acid (TFA). Modification of these triptycene-based bisanilines has led to the formation of TB-PIMs, all with distinctive gas permeation properties. TB-PIM copolymers (reaction between two different bisaniline monomers with DMM and TFA) were synthesised in an attempt to further tune the performance of the polymers. Finally, the preparation of polybenzodioxan polymers based around extended triptycene monomers (i.e. benzotriptycenes) was studied. By using a variety of substituted benzotriptycene biscatechol monomers and performing the polymerisation using tetrafluoroterephthalonitrile, in the presence of K2CO3, the synthesis of a series of substituted benzotriptycene polybenzodioxane polymers was successfully achieved and the polymers showed enhanced gas permeation properties.

Poly(vinylidene fluoride) PVDF is a semi-crystalline fluoropolymer that attracted researchers' attention more than a decade ago due to its remarkable properties, such as mechanical strength, thermal stability, chemical resistance, good processability, and excellent aging resistance. Due to these excellent properties, PVDF is applied in many applications such as membranes and filtration, biomedical applications, drug delivery, batteries, energy generation, energy storage, sensors, actuators, and energy harvesting applications. The dissertation was inspired by PVDF’s outstanding properties and applications. First of all, the effect of chain topology of on the crystallization and polymorphism between linear and star PVDF homopolymers were studied. Well-defined linear and stars PVDF homopolymers architectures were synthesized by reversible addition−fragmentation chain transfer (RAFT) polymerization. The non-isothermal crystallization study showed an increase in the amount of ferroelectric β-phase with respect to the paraelectric α-phase as the number of arms in the PVDF stars increases. This finding is explained by the increased topological complexity in the stars of several arms, which leads to the preferential formation of the less thermodynamically stable ferroelectric β-phase. Moreover, the isothermal crystallization kinetics of the PVDF stars was faster than the linear PVDF as a result of their speedier nucleation. Secondly, we report the synthesis of poly(n-isopropylacrylamide)-b-poly(vinylidene fluoride) (PNIPAM-b-PVDF), amphiphilic block copolymers with linear and star architectures by RAFT sequential living polymerization. Due to the presence of a lower critical solution temperature (LCST) for PNIPAM (coil-globule transition around 32 °C), the synthesized PNIPAM-b-PVDF block copolymers have thermo-responsive behavior, therefore, potential application in the fabrication of thermo-responsive membranes. All fabricated membranes by nonsolvent-induced phase separation (NIPS) method exhibited thermo-responsive behavior with water permeability and PEG rejection experiments. Moreover, the several heating-cooling cycles showed that the thermal-responsive behavior of these membranes are reversible and stable. Finally, a suggested potential future work is given to synthesize other PVDF-based block copolymers via sequential living polymerizations.