Related Products of 1779-49-3In 2019 ,《Effect of the Substituent Position on the Anionic Copolymerization of Styrene Derivatives: Experimental Results and Density Functional Theory Calculations》 appeared in Macromolecules (Washington, DC, United States). The author of the article were Johann, Tobias; Leibig, Daniel; Grune, Eduard; Mueller, Axel H. E.; Frey, Holger. The article conveys some information:
In a combined synthetic, kinetic and theor. study, the living anionic copolymerization of styrene and its ring-methylated derivatives ortho-, meta-, and para-methylstyrene (MS) was examined by real-time 1H NMR spectroscopy in the nonpolar solvents toluene-d8 and cyclohexane-d12 as well as by d. functional theory calculations Based on the NMR kinetics data, reactivity ratios for each comonomer pair were determined by the Kelen-Tudos method and numerical integration of the copolymerization equation (Contour software). The reaction pathway was modeled and followed by d. functional theory (DFT) calculations to validate and predict the exptl. derived reactivity ratios. Unexpectedly, two of the three styrene derivatives showed completely different reactivities in copolymerization, governed by the position of the Me group. While para-MS is considerably less reactive than styrene, resulting in gradient copolymers (rS = 2.62; rpMS = 0.37), ortho-MS showed the opposite behavior and is more reactive than styrene (rS = 0.44; roMS = 2.47), leading to a reversal of the copolymers’ gradient. The substitution in the meta-position had nearly no influence on monomer reactivity, and copolymers with close to random comonomer distribution were formed (rS = 0.81; rmMS = 1.21). In all cases, the theor. calculations showed good to excellent agreement with the exptl. data. Monomer reactivities correlate with the chem. shifts of the β-carbon signals in 13C NMR spectra that are predictive for the gradient structure. The results demonstrate the possibility of tailoring and validating the polymer structures of functional polystyrene copolymers by the choice of the substitution pattern of styrene derivatives, using both exptl. and theor. approaches. In the part of experimental materials, we found many familiar compounds, such as Methyltriphenylphosphonium bromide(cas: 1779-49-3Related Products of 1779-49-3)
Methyltriphenylphosphonium bromide(cas: 1779-49-3) is a lipophilic molecule with a cation allowing for it to be used to deliver molecules to specific cell components. Also considered an antineoplastic agent.Related Products of 1779-49-3
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary