Amphiphilic polymer co-networks: 32 years old and growing stronger – a perspective.  Costas S Patrickios* and Krzysztof Matyjaszewski

This brief perspective overviews amphiphilic polymer co-networks (APCNs), polymeric chemically crosslinked hydrogels also covalently hosting a hydrophobic segment, conferring upon these materials the important property of internal selforganization in aqueous environments. APCN synthesis is most conveniently accomplished via the random crosslinking copolymerization of a hydrophilic monomer with a hydrophobic macro-crosslinker, whereas better structures are attained via the end-linking of amphiphilic linear ABA triblock copolymers or amphiphilic star diblock copolymers. Microphase-separated morphologies, translucency-to-transparency, biocompatibility, low to moderate aqueous swelling, fair mechanical strength and possible stimulus-responsiveness constitute the main physicochemical properties of APCNs, with their major commercial application being in silicone hydrogel soft contact lenses. Modeling the swelling, morphological and mechanical behavior of these intriguing materials is an area where more progress is necessary in order to improve our understanding of these networks and facilitate the design of next-generation APCNs.© 2020 Society of Industrial Chemistry