Amide-Functionalized Polyolefins and Facile Post-Transformations

Abstract

Direct copolymerization of olefins with polar monomers to produce functionalized polyolefins has attracted much attention; however, highly efficient incorporation of amide functions into polyolefins is a long-standing challenge because the amide function is pronounced to retard chain growth. In this contribution, Vince Lactam’s derivatives (VLH, VLMe, and VLBoc) that contain high ring strain and an amide moiety are utilized in ethylene copolymerization mediated by palladium catalysts. Amide-functionalized polyethylenes, poly(E-VLBoc)s, are accessible with key characteristics of high amide incorporations (up to 30.1 mol %), high copolymer molecular weights, and high catalytic activities. The incorporation of the amide comonomer converts crystalline poly(E-VLBoc)s (Tm = 115–125 °C) to noncrystalline and transparent poly(E-VLBoc)s (Tg = 98–196 °C, optical transmittance (T) = 87.6%–90.4%). Both characteristics of cyclic amide functions and high amide incorporations in poly(E-VLBoc) enable facile post-transformations under mild conditions to produce hydrogen bond-containing (-C(O)NH-) poly(E-VLH), difunctionalized (-COOH and -NHR) poly(E-VLNHBoc), and water-soluble ammonium-functionalized poly(E-VLNH3+). The ammonium functionality endows polyolefin with antibacterial properties.