Novel acrylic monomers functionalized with nucleobase-containing units (adenine and thymine) were prepared upon aza-Michael addition and successfully copolymerized with nbutyl acrylate. At a content of 7 mol %, adenine-containing units self-assembled into needle-like microstructures within amorphous polymer matrices as shown with atomic force microscopy (AFM), small-angle X-ray scattering (SAXS), and wide-angle X-ray diffraction (WAXD); thymine-containing units did not aggregate into distinct morphologies even to 30 mol %. Upon blending, thymine-and adenine-containing statistical copolymers associated into a thermodynamically stable complex, which was physically cross-linked through adenine−thymine base pairing. The molar fractions of the nucleobase monomer, nucleobase stacking interactions, and complementary hydrogen bonding principally influenced self-assembly. Additionally, the nucleobasefunctionalized polyacrylates exhibited tunable adhesive and cohesive strength.

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Adenine-and thymine-functionalized ammonium ionenes with variation in spacer lengths are successfully synthesized using the Michael addition post-polymerization functionalization. This report describes the infl uence of pendant spacer length on homoassociation and heteroassociation of complementary nucleobase-containing ionenes. The ionene homopolymers and complementary blends with various spacer lengths show a single glass transition temperature. Higher glass transition temperatures are observed for the shorter-spacer ionene homopolymers and their blends. The hydrogen bonding interactions in both blends of adenine-containing ionenes (ionene-A) and thymine-containing ionenes (ionene-T) with both spacer lengths are studied using differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) spectroscopy, and atomic force microscopy (AFM). DSC analyses do not reveal hydrogen bonding interactions in the ionene blends with the shorter spacer length. In contrast, the longer spacer length ionene blends show the presence of hydrogen bonding interactions and demonstrate that homoassociation is stronger than heteroassociation. FTIR spectroscopy and AFM confi rm hydrogen bonding interactions for the longer spacer ionene blends.