Synthesis and Characterization of Novel Complementary Multiple-Hydrogen Bonded (CMHB) Macromolecules via a Michael Addition

Abstract

The synthesis and characterization of novel complementary multiple hydrogen-bonded poly(styrene) (CMHB-PS) oligomers possessing controlled molecular weights and narrow molecular distributions are described. Novel CMHB-PS oligomers comprising terminal heterocyclic base units were synthesized in a controlled fashion via derivatization of well-defined hydroxyl-terminated PS. The heterocyclic-terminated oligomers were synthesized via a Michael addition of the corresponding heterocyclic compounds such as adenine, thymine, and 2,6-purine with acrylated PS. The acrylated PS precursors were prepared in a quantitative fashion via reaction of hydroxyl-terminated PS with acryloyl chloride in the presence of triethylamine. Terminal heterocyclic bases were introduced via a Michael addition in the presence of potassium tert-butoxide (t-BuOK). Novel CMHB-PS aggregates were prepared via subsequent solution blending of PS with complementary heterocyclic base units. 1H NMR analysis confirmed that a 1:1 mixture of adenine-PS or purine-PS with thymine-PS formed complementary multiple hydrogen bonding and exhibited thermoreversibility. In addition, 1H NMR analysis confirmed that complementary hydrogen bonds dissociated at 95 °C in deuterated toluene.