| Selenium-containing polymers have attracted considerable attention due to their unique properties, which show wide application as photoelectric materials and biomedical materials. For examples, selenophene polymers have been considered as effective photoelectric materials which may be widely used in near future. Due to special outer electronic structure, selenium-containing polymers show versatile responsive behavior with multi stimulus, such as oxidation, reduction and irradiation. Such unique properties and nutrition effect make selenium-containing polymers as potentially useful building block for bio-related materials.However, the current synthetic methods of selenium-containing polymers are limited, mainly including following routes: the polymerization of selenium-containing monomers; organic selenide mediated polymerization of vinyl monomers; organoselenium-mediated radical polymerization of vinyl monomers. Nonetheless, these currently synthetic routes show obvious shortcomings, which cannot been overlooked. The structure of selenium-containing monomers are limited, and polymerization activity is low. Normally, copolymerization is needed. The polymers obtained from selenide mediated polymerization show limit in structure controlling. The polymers obtained from organoselenium-mediated radical polymerization show shortcoming in the limited in structure, e.g. only selenium in chain end could be prepared. Thus, it is important to develop new synthetic route for the fabricating of selenium containing polymers with both controlled structures and controlled selenium concentration.Based on this demand, this thesis focused on the developing of new synthetic routes for fabricating selenium-containing polymers with well-defined structures and controlled selenium concentration. The main content include the following aspects.(1) Diselenide-containing polymers are synthesized by the reaction between atom transfer radical polymerization(ATRP) derived polymers and Na2Se2. By using polystyrene as the model polymer, well-defined diselenide-containing polymers with controlled molecular weight and narrow molecular weight distribution are prepared. The structure is well characterized using GPC, UV-vis spectrum, 1H NMR, MALDI-TOF MS, and 77 Se NMR. Same synthetic procedure is applied to other polymers prepared by ATRP, such as polymethacrylate and poly(polyethylol methacrylate). Block copolymers with diselenide linkage also are fabricated by the cross reaction for these different polymers. In addition, the redox responsive behavior of these diselenide-containing polymers are verified. Such diselenide-containing polymers are further used as stabilizing agent to fabricating golden nanoparticle, which introduce redox responsive ability into golden nanoparticle materials.(2) The ATRP derived polystyrene is further reacted with selenium functionalized resin(Se BER), which results in a well-defined selenide containing polymers. Such procedure shows advantages in extremely high efficiency, e.g. near 100% conversion under room temperature with several minutes’ reaction time. The selenide structure in polymer is verified by GPC, 1H NMR, and MALDI-TOF MS. Such synthetic route also could be extended to those polymers prepared by reversible addition-fragmentation chain transfer polymerization(RAFT). The structure of polymers could be verified, such as but not limited to poly(vinyl acetate), poly(methyl acrylate), and poly(N-vinyl pyridine) etc. Furthermore, by changing the reacting polymer from mono-functional to multi-functional, complicated topological polymers, such as block, cyclic-shape and eight-shape, are successfully synthesized.In summary, the current thesis develops the effective synthetic route for fabricating diselenium-containing and selenium-containing polymers with well-defined structure and selenium concentration, which should be valuable for the potential application for these materials in the future. |
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