Influence of the rosin side-chain groups on the solution properties of a high molecular weight hydrogenated poly(norbornene)

[摘要] The dilute solution properties of a sample of high molecular weight rosin substituted hydrogenated polynorbornene (hPDNB) homopolymer, prepared via ROMP and post-polymerization modified by backbone hydrogenation, was investigated by the online measurement of intrinsic viscosity, refractive index, two-angle light scattering and size exclusion chromatography (SEC) in tetrahydrofuran (THF) at 35 degrees C. The weight average molecular weight ((M) over bar (w)), intrinsic viscosity ([eta]), radii of gyration ((R) over bar (G)) and hydrodynamic ((R) over bar (H)) radii, and concentration of the polymer fractions obtained from corresponding traces of the chromatograms. From these data, the double logarithmic plots of (M) over bar (w) versus [eta], (M) over bar (w) versus (R) over bar (G) and (R) over bar (H), and [eta](M) over bar (1/2)(w) versus (M) over bar (1/2)(w) scaled the dimensions of the polymer chains to molar mass. The results, surprisingly, indicated that the rosin-substituted poly (norbornene) is flexible like poly(methyl acrylate). To confirm the results, the data were analyzed by the wormlike touched-bead model which predicated the polymer to be more rigid than poly(methyl acrylate) but less rigid than hindered poly(di-alkyl phenyl acrylate) and poly(di-tert-butyl fumarate).

[发布日期] 2021-10-12

[关键词] Polynorbornene;Rosin;Viscosity;Flexibility;Mark-houwink;Stockmayer-Fixman;Touched-bead model