Effect Of ?-? Stacking On The Radical Copolymerization Of 2,5-diphenylstyrene

?-? interactions exist widely in many fields of biological, chemical, materials, as particularly important non-covalent forces, encourage the people have been studied in different directions. For example: the conformation of biological macromolecules, drug design, host-guest chemistry, molecular recognition and crystal engineering and so on. This work was used a four step organic chemistry reaction to synthesize target monomer 2,5-diphenylstyrene (DPS), and by nuclear magnetic resonance (1H NMR), carbon nuclear magnetic resonance (13C NMR) and infrared spectroscopy (IR) to characterize its structure.The copolymer of 2,5-diphenylstyrene and 2,3,4,5,6-pentafluorostyrene (PFS) was synthesized by free radical polymerization (FRP) and atom transfer radical polymerization(ATRP), and using three different methods to calculate the monomer reactivity ratios.Copolymer tended to be alternating structure, and it was caused by ?-? interactions between copolymer of DPS and PFS.The free radical polymerization of 2,3,4,5,6-pentafluorostyrene and 2,5-diphenylstyrene was reacted at 70 ? in toluene. The values of monomer reactivity ratios were calculated by three different methods: Fineman-Ross equation (rDPSxrPFS=0.02), Kelen-Tudos equation(rDPSxrPFS = 0.07),nonlinear least squares method (rDPs×rPFS=0.07). Compared reactivity ratios with 25?,70 0C by free radical polymerization methods in toluene,we can see that lower temperature with smaller reactivity ratio value,and indicated that with the temperature decreases, the presence of ?-? interactions between DPS and PFS was stronger. And the copolymer of 2,5-diphenylstyrene and 2,3,4,5,6-pentafluorostyrene was characterized by 1H-13C HSQC and 1H-1H NOESY and thermal properties test, results showed that the structure of copolymer tend to be alternating and that was caused by ?-? interactions between DPS and PFS.The atom transfer radical polymerization of 2,3,4,5,6-pentafluorostyrene and 2,5-diphenylstyrene was at 70? in toluene and heptane, the values of monomer reactivity ratios were rDps×PFs = 0.29 and rDPS×rPFs = 0.19 calculated by nonlinear least-squares methods (NLLS). Compared two reactions with different solvent toluene and n-heptane to obtain the reactivity ratio values, demonstrated that both comonomer pairs tend to be alternating, this dues to the ?-? interactions between DPS and PFS, and in n-heptane easier to form an alternating copolymer, in a non-aromatic hydrocarbon solvent is more conducive to form ?-? interactions.