Advanced Polyamides by a Radical Pathway – PAradIsiac

Polyamides (PA) are polymers with worldwide importance for a diverse range of applications. Indeed intermolecular hydrogen bonding interactions confer outstanding properties to PA (high mechanical strength, toughness, flexibility and resistance). PA are commonly prepared by polycondensation or anionic ring-opening polymerization, syntheses with a limited selection of monomers and drastic reaction conditions. With their renowned Rilsan@ and Pebax@ trademarks, ARKEMA is one of the world main producer of polyamide products. They are widely used in electronic and transportation, textiles, etc. Even if polyamides are important engineering plastics due to excellent performances such as good processability, mechanical strength and abrasion resistance, some limitations are still present and represent a room of innovation for advanced polyamides materials.

The aim of the project is to propose a new methodology for the elaboration of PA through the radical ring-opening (co)polymerization of 1,3-oxaza-heterocyclic ketene monomers called O,N-cyclic ketene acetals (O,N-CKA) with common vinyl monomers to introduce amide bonds into vinyl polymer backbones (i.e. elaboration of copolymers with amide parts creating hydrogen bonding) and to design functionalized PA complex macromolecular architectures. Four different applications will be targeted. In particular introduction of functional group that will bring enhanced surface adhesion (Silicium, Phosphorous or Sulfur containing monomers), fire resistance (Phosphorous-based monomers), control of hydrophilicity (polar or hydrophobic monomers) and softness (Long alkyl chain monomers) will be targeted. A special attention will be dedicated to the synthesis of polyamide vitrimers.

The interest of O,N-CKA monomers is also related to the incorporation of small amount of amide groups inside the polymer backbone. These groups could be seen as intermolecular hydrogen bonding groups and thus promote interactions between polymer chains, thereby increasing the thermal and chemical resistance of the materials, as well as their mechanical properties. The copolymerization of classic vinyl monomers with a lower ratio of O,N-CKA monomers could lead to materials similar to the PEBAX@ with enhanced properties (hydrolytic stability, better mechanical property, better chemical resistance, better scratch resistance, tuning of the hydrophilicity and better temperature stability).

In conclusion, combining the outstanding physical properties of PA with the ease of radical polymerizations will lead to the development of innovative materials relevant to a wide range of industrial applications.