Skip To Main Content
L. Heymann on Muck Rack

L. Heymann

As seen in: Analytical Chemistry
Is this you? As a journalist, you can create a free Muck Rack account to customize your profile, list your contact preferences, and upload a portfolio of your best work. Claim your profile
Back to L. Heymann’s profile

Articles by L. Heymann

Dynamics of a Paradigmatic Linear Polymer: A Proton Field-Cycling NMR Relaxometry Study on Poly(ethylene-propylene)

|
By M. Hofmann, B. Kresse, L. Heymann, A. F. Privalov
| Analytical Chemistry Verified
The dynamics of melts of linear poly(ethylene-alt-propylene) (PEP) of different molar masses (M) is investigated by 1H field-cycling (FC) NMR relaxometry. Employing a commercial and a home-built relaxometer the spin-lattice relaxation rate R (?) is measured in the frequency range of 200 Hz to 30 MHz and the temperature range of 200–400 K.
Open in Who Shared Issue with article?

Segmental Mean Square Displacement: Field-Cycling 1H Relaxometry vs Neutron Scattering

|
By M. Hofmann, B. Kresse, A. F. Privalov, L. Heymann
| Analytical Chemistry Verified
Proton (1H) field-cycling (FC) NMR relaxometry is applied to monitor the crossover in the segmental subdiffusion from the Rouse to the constrained Rouse regime in an entangled linear polymer melt. The method probes the dispersion of the spin–lattice relaxation rate R (?). Via Fourier transformation the segmental mean square displacement ?r2(t)? is calculated from the intermolecular relaxation contribution R inter(?) to the total 1H spin–lattice relaxation dispersion R (?).
Open in Who Shared Issue with article?
Show More