Study of translational dynamics in molten polymer by variation of gradient pulse-width of PGSE

作者：Stepisnik Janez^*; Lahajnar Gojmir; Zupancic Ivan; Mohoric Ales

来源：Journal of Magnetic Resonance, 2013, 236: 41-46.

DOI：10.1016/j.jmr.2013.08.003

• Magnetic resonance
• Molten polymers
• Diffusion
• Gradient spin echo
• Rouse model
• Tube/reptation
• Velocity correlation function

Pulsed gradient spin echo is a method of measuring molecular translation. Changing A makes it sensitive to diffusion spectrum. Spin translation effects the buildup of phase structure during the application of gradient pulses as well. The time scale of the self-diffusion measurement shortens if this is taken into account. The method of diffusion spectrometry with variable delta is also less sensitive to artifacts caused by spin relaxation and internal gradient fields. Here the method is demonstrated in the case of diffusion spectrometry of molten polyethylene. The results confirm a model of constraint release in a system of entangled polymer chains as a sort of tube Rouse motion.

• 出版日期2013-11