Abstract
New porous synthetic membranes with controlled morphologies and performances were prepared by using block copolymers. Such macromolecules can self-organise into structures with well defined geometries and are also able to have an influence on the interface curvature. New ABA triblock copolymers, having a poly(ethylene oxide) center block and two poly(styrene) end blocks, were prepared using an original synthesis strategy consisting in the combination of chemical modification of end chains and in nitroxide controlled radical polymerization. Then, various morphologies formed by self-assembling of these block copolymers as thin films were studied as a function of their structure and operating parameters (evaporation rate, concentration ...etc). From these results, new model membranes having organised cylindrical pores with a calibrated and controlled nanometric size were prepared. Moreover, the synthesis of other amphiphilic triblock copolymers was developed using a multi-step approach integrating a polycondensation. These copolymers are made of a center aromatic poly(ether imide) hydrophobic block and two poly(ethylene oxide) hydrophilic end blocks. Then, membranes with well defined use properties were developed controlling their design mechanisms, either by mean of the process parameters, or by adding triblock copolymers in the formulation. Due to their interfacial self-organization properties, the latter were used as additives in a poly(ether imide) solution where a non-solvent induced phase separation takes place. Lastly, performances of all prepared membranes in this work have enabled to validate the two proposed approaches.