In order to reduce friction and wear of mechanical seals, studies show that SiC-based ceramic textured surfaces are a promising solution ¹. In this project two methodologies are combined to synthetize nanostructured ceramics. First, the intrinsic properties of block copolymers are used to generate textured surfaces at the nanoscale. Indeed, block copolymers - the combination of two polymer chains linked together by a covalent bond – allow the formation of nanostructured films on surface due to the chemical incompatibility between the two blocks. Depending on the volume ratio between the two blocks, their chemical nature, the total degree of polymerization, it is possible to modify the morphology, periodicity or size of the objects formed on the surface ². In this study, one of the block is a polycarbosilane that can be transformed in a ceramic with the appropriate thermal treatment and the other is a “sacrificial” polystyrene block ³. The Polymer-Derived Ceramics (PDCs) route allows a polycarbosilane, called a preceramic polymer, to form a ceramic through a controlled thermal treatment. Accordingly, polycarbosilane-b-polystyrene (PC-b-PS) block copolymers were synthesized by sequential anionic polymerization and nanostructured films were produced by depositing a block copolymer solution by spin coating followed by an annealing treatment to promote self-assembly. Then a thermal treatment could lead to the transformation of the preceramic PC domains into silicon carbide (SiC) ⁴, while the sacrificial PS domains are concomitantly removed during this step ⁵. We analyzed the influence of the macromolecular parameters, thermal treatments and additives on the formation of nanostructured ceramics.

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