Preparation and characterisation of membranes containing liquid crystal copolymers with improved proton conductivity for their use in DMCF and DEFC

Abstract

The main aim of this Master Thesis is to prepare membranes (LCM) containing liquid crystal polymers (LCP) with appropriate mechanical and diffusion properties for their future use as electrolytes in DMFC and DEFC. This work focus on the preparation methods for obtaining membranes from liquid crystal polymers and in the set up of absorption tests to measure their diffusion properties respect to water and alcohols. In order to achieve the main aim of the Master Thesis, the work will be divided in the following partial aims:

1. Preparation of materials (liquid crystal polymers, LCP). 2. Preparation of membranes containing liquid crystals (LCM). 3. Set up absorption tests to study solvents selectivity. Aims 1 and 2 involve the study of the preparation methods and the effect of composition on the properties of the resulting membranes. The structure of the materials and membranes will be characterised by IR Spectroscopy and Thermal Analysis. The selection of methods and conditions will be carried out considering the quality of the resulting materials. The set up of the absorption tests (Aim 3) is crucial to prepare experiments which allows for the determination of the selectivity of the membranes respect to water and methanol (in DMFC) and ethanol (in DEFC). In this Master Thesis, two different tests will be carried out: absorption in vapour phase (low pressure) and experiments in liquid phase (saturation).