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Author
Earl, W. L. | VanderHart, D. L.
Title
Observations in Solid Polyethylenes by Carbon-13 Nuclear Magnetic Resonance With Magic Angle Sample Spinning.
Coporate
National Bureau of Standards, Gaithersburg, MD
Journal
Macromolecules, Vol. 12, No. 4, 762-767, July/August 1979
Keywords
polyethylenes | cross polarization | nuclear magnetic resonance
Abstract
It is shown that the (13)CNMR resonance lines of the crystalline component (CC) and the noncrystalline component (NCC) in polyethylene (PE) are chemically shifted from one another. This usually produces and upfield shoulder on the CC resonance line in a "cross-polarization with magic angle sample spinning" (CPMASS) experiment. Two peaks were resolved in a low crystallinity, high molecular weight sample, the NCC peak being 2.36 ±0.1 ppm upfield from the CC peak.