TY  - JOUR
AU  - Wischnewski, A.
AU  - Monkenbusch, M.
AU  - Willner, L.
AU  - Richter, D.
AU  - Kali, G.
TI  - Direct observation of the transition from free to constrained single-segment    motion in entangled polymer melts
JO  - Physical review letters
VL  - 90
SN  - 0031-9007
CY  - College Park, Md.
PB  - APS
M1  - PreJuSER-28406
SP  - 058302
PY  - 2003
N1  - Record converted from VDB: 12.11.2012
AB  - We report a direct determination of the time dependent mean-squared segment displacement of a polymer chain in the melt covering the transition from free to constraint Rouse relaxation along the virtual tube of the reptation model. This has been achieved by a neutron spin-echo (NSE) measurement of the segmental self-correlation function as conveyed by the spin-incoherent scattering from two fully protonated polymer melts, polyethylene and polyethylene propylene. Within the scenario of de Gennes reptation model a transition of the time dependence of segmental mean-squared displacements from proportional tot(1/2) to proportional tot(1/4) is expected and clearly corroborated by the incoherent NSE results.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000180918300062
DO  - DOI:10.1103/PhysRevLett.90.058302
UR  - https://juser.fz-juelich.de/record/28406
ER  -