WebApr 13, 2024 · On the other hand, the tacticity of PMMA samples generated using electric fields of 77 kV cm −1 and frequencies 1 Hz or 50 Hz are almost the same. In Fig. 2(d) , we … WebThe methyl protons are better resolved in pyridine due to solvent effects such as ring current shielding of the aromatic ring and electric field effect from the nitrogen lone pair. As an aid for the tacticity assignments, two-dimensional NMR spectra of poly(DL-lactic acid) (L/D=50/50) and relative intensities of PLA samples have been used.
Chain dynamics and intermolecular association in dilute aqueous ...
WebIn the aPMA case, aggregation and phase separation take place with increasing temperature, whereas with iPMA intermolecular associates gradually disintegrate upon heating the solutions; however, no macroscopic phase separation is observed, and the … WebSteric Arrangement in Polymers (Tacticity) The physical properties of a polymer depend not only on the type of monomer(s) that make up the polymer but also on the stereochemical arrangements of the atoms. In a linear asymmetric polymer chain, the pendant groups can either be arranged into orderly configuarations or they can be completely random. gilbert o\\u0027sullivan greatest hits cd
Tacticity - Wikipedia
WebMar 3, 2015 · For the first time, thermal field-flow fractionation (ThFFF) has been used for the separation of poly (methyl methacrylate) (PMMA) with regard to molecular … WebApr 18, 2012 · This paper reports multivariate analyses such as principal component analysis and partial least-squares regression of NMR spectra of poly(N … WebJan 1, 1993 · This chapter discusses the application of high-resolution NMR spectroscopy to polymer chemistry. Like many scientific fields, polymer chemistry has benefited from the introduction of NMR spectroscopy, and it is now widely used in areas such as tacticity determination, analysis of end-groups and irregular linkages, comonomer sequence … ftmyres fl gun show