Click Polymerization Based On Alkynes

The development of polymerization methodologies is of academic value and technological implication. Polymers such as plastics, fibers and rubbers based on alkenes are often used in daily life and industry. In contrast, the research and application of polymers based on alkynes is very rare. However, the reaction types of alkynes are tremendous and products bearing double-bonds, triple-bonds or(hetero)aromatic rings could be generated. The resulting polymers are rich in π-electrons which endow polymers with luminescence, photoconductivity, chromatism, optical nonlinearity, refractivity and photochemical patternability. Click polymerizations based on alkynes, especially Cu(I)-catalyzed alkyne-azide polymerization, with the advantageous characteristics of mild reaction condition, high efficience and high selectivity have gained wide attention from polymer scientist. To make the click polymerization more applicable, more types of them should be developed.With this in mind, in this thesis, an organic base mediated click polymerization was successfully developed through systematic optimization of reaction conditions, such as temperature, catalyst concentration and reaction time. Using aromatic alkyne and azide monomers, 1,5-regioregular polytriazoles were obtained with high yields at room temperature in the presence of water soluble NMe4 OH. The regioselectivity of this polymerization was very high(the fraction of 1,5-disubstituted 1,2,3-triazole was up to 100%). The polymers are soluble in common solvents.K3PO4 mediated thiol-yne click polymerization based on aromatic diynes was successfully developed. Poly(vinylene sulfide)s(PVSs) with high regioregular(sole anti-Markovnikov) and stereoregular(fraction of Z isomers up to 100%) were obtained with high molecular weights and high yields. The obtained PVSs are soluble and thermally stable and prossess high refractive indices. The tetraphenylethene(TPE) containing PVSs show a unique feature of aggregation-induced emission and the quantum yield in the solid state was up to 20.7%. The properties of optical nonlinearity was also developed.We also successfully developed the click polymerization based on electron-rich internal alkyne monomers using [Ir(cod)Cl]2 as catalyst. Fully substituted sulfer-containing polytrizaoles were obtained with high regioregularity. The produced polymers are soluble and thermally stable. This polymerization overcomed the challenge that the electron-rich alkyne monomers could not react with azides and expanded the applicable range of click polymerization, providing a powerful tool to prepare polymers with advanced functions.