Measurements of polymer diffusion over small distances. A check of reptation arguments
نویسندگان
چکیده
We performed neutron reflectrometry ~NR) and nuclear reaction analysis ~NRA) measurements on interdiffusion of protonated and deuterated polystyrene films Covenng several orders of magnitude in time i and resolving interfacial widths w(i) between approximately 2 nm and 60 nm we found two successive time regimes with a crossover corresponding to the reptation
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