Determining Structure of Paraffinic Chains by NMR.

Intramolecular hydride shift polymerization by cationic mechanism. VII. The polymerization of 4‐methyl‐1‐hexene

“…This absorption is at slightly higher field than that for the geminal dirnethyl groups in cationic 1,3-poly(4-rnethyl-l-pentene) (7) which is found a t 0.82 ppm. The peak a t 0.88 pprn represents the center of a triplet arising from the methyl group in the ethyl s i d e chain, its chemical shift is in excellent agreement with the expected value (8). The broadened and slightly split peak at 1.18 ppm represents the 3 methylene groups i n the backbone, apparently somewhat nonequivalent because of the different substituents on the quarternary carbon.…”

Structural Features and Pyrolysis Behaviors of Extracts from Microwave-Assisted Extraction of a Low-Rank Coal with Different Solvents

“…As for aliphatic protons, H α and H β are dominant for two extracts, suggesting the existence of branched alkyl side chains in the α- and β-position to the aromatic rings, such as methyl, methylene, and/or methine. In addition, two samples show multiple peaks in 1.0–2.0 ppm, indicating the existence of both paraffinic and naphthenic methylene structures . Additionally, a weak peak can be observed at 5.7 ppm, indicating that there exist some phenolic-containing species in E CYC .…”

“…In addition, two samples show multiple peaks in 1.0−2.0 ppm, indicating the existence of both paraffinic and naphthenic methylene structures. 51 Additionally, a weak peak can be observed at 5.7 ppm, indicating that there exist some phenolic-containing species in E CYC . The above results suggest that more organic matters can be extracted by CYC than THF during MAE process.…”

The NMR of Polymers

“…53) shows a broad component with a distance between the extrema greater than 15 OeD When the film is turned along the field, for a considerable part of the CH 2 groups e ~ 90° and the line narrows. In oriented polyethylene fiber a change has been observed in the form of the line in relation to the angle between the fiber and the field vector (see page 168).…”