판상형 단량체를 사용한 고분자 물질의 합성고 응용

Abstract

This thesis describes the synthesis, characterization and applications of polymeric materials made of flat monomers with rigid, disk-shaped structures at the core and multiple polymerizable units at the periphery via covalent self-assembly. The flat, disk-shaped monomers such as phthalocyanine (Pc), triphenylene (TP) and (allyloxy)12cucurbit[6]uril ((allyloxy)12CB[6]) have been successfully incorporated into polymeric materials such as polymer nanoballs and two-dimensional (2D) polymers via thiol-ene “Click” chemistry. Furthermore the optical properties of phthalocyanine and the host-guest chemistry of CB[6] are exploited to investigate and manipulate the physical properties of the polymeric materials for applications.Chapter 2 describes a one-pot, direct construction of fluorescent polymer nanoballs composed of photosensitive chromophores without using any template. Pc and TP derivatives which have rich optical and electronic properties were chosen as polymerizable disk-shaped monomers to be incorporated into the shell of polymer nanoballs. Polymer nanoballs composed of Pc and TP were directly prepared via the thiol-ene “Click” chemistry. The size and shape of the nanoballs were modulated by the polarity of the reaction medium. In addition, the fluorescence anisotropy and lifetime of the Pc nanoballs were also investigated. Furthermore incorporation of molecular cavities into the shell of the nanoballs was carried out by simply adding the (allyloxy)12CB[6] as a cocktail monomer, which allowed us to introduce interesting functional groups to their surface via strong host-guest interactions without changing the structure of the nanoballs. These materials may thus be useful as a targeted drug or gene delivery carrier and nanoreactor. Chapter 3 presents the application of zinc phthalocyanine (ZnPc) nanoballs in photodynamic therapy (PDT) to destroy the cancer cells in vitro and in vivo. Cellular uptake of the ZnPc nanoballs into human squamous cell carcinoma cell line (KB cells) under a general culture condition and a low temperature condition showed that the ZnPc nanoballs were well internalized into the cytosol through energy-dependent endocytosis. Cell cytotoxicity assays confirmed that the ZnPc nanoballs have almost no dark toxicity in the absence of light, whereas in the presence of light they exhibit a high photodynamic activity against the KB cells. Furthermore, in vivo PDT tests on C57BL/6 mice model were also successfully carried out. Upon irradiation, the growth of TC-1 tumor was suppressed by a single injection of the ZnPc nanoballs both intratumorally and intravenously.Chapter 4 describes the unconventional synthesis of single monomer thick 2D polymers in solution as well as water-oil interface. The thiol-ene “Click” reaction of (allyloxy)12CB[6] and dithiol linkers directly produced free-standing 2D polymers with a wide range of sizes from several hundred nanometers to a few micrometers in N,N-dimethylacetamide and from a few micrometers to a few millimeters at water-toluene interface. A TEM study indicated that the 2D polymers were thin and flexible enough to be broken, crumpled and rolled by the electron beam. The molecular cavity in the 2D polymers also formed a strong complex with a spermine-dye conjugate, which allowed us to visualize 2D polymers under fluorescence microscope to investigate their dynamic behaviors in solution. In addition, gold nanoparticles were selectively anchored on the each CB[6] units of spermidine-decorated 2D polymers via Nanogold？？- amine interactions, which helped to visualize the 2D array of CB[6], the replica of the internal structure of 2D polymers.