TY - JOUR
T1 - Segmental dynamic heterogeneity of short-chain grafted-poly(dimethylsiloxane) by 1H spin-diffusion NMR
AU - Bertmer, Marko
AU - Demco, Dan E.
AU - Wang, Mingfei
AU - Melian, Claudiu
AU - Marcean-Chelcea, Ramona I.
AU - Fechete, Radu
AU - Baias, Maria
AU - Blümich, Bernhard
N1 - Funding Information:
Financial support of this project by the Deutsche Forschungsgemeinschaft (DE 780/2-1) is gratefully acknowledged. The authors are grateful to Dr. V.M. Litvinov for useful discussions.
PY - 2006/11/24
Y1 - 2006/11/24
N2 - Segmental dynamic heterogeneity of short-chain grafted poly(dimethylsiloxane) (PDMS) on pyrogenic silica was investigated using 1H NMR spin-diffusion. A double-quantum dipolar filter was employed for selection of the interface (rigid) region. One-dimensional spin-diffusion equations were solved numerically for a space distribution of spin diffusivity D(x) of the mobile PDMS chains. The degree of heterogeneity can be quantified by the parameters of Gaussian and exponential diffusivity distribution functions which yield similar diffusivities. The rigid and mobile domain sizes and spin diffusivities were correlated with the PDMS chain length, the temperature, and 1H residual dipolar couplings.
AB - Segmental dynamic heterogeneity of short-chain grafted poly(dimethylsiloxane) (PDMS) on pyrogenic silica was investigated using 1H NMR spin-diffusion. A double-quantum dipolar filter was employed for selection of the interface (rigid) region. One-dimensional spin-diffusion equations were solved numerically for a space distribution of spin diffusivity D(x) of the mobile PDMS chains. The degree of heterogeneity can be quantified by the parameters of Gaussian and exponential diffusivity distribution functions which yield similar diffusivities. The rigid and mobile domain sizes and spin diffusivities were correlated with the PDMS chain length, the temperature, and 1H residual dipolar couplings.
UR - http://www.scopus.com/inward/record.url?scp=33750633935&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33750633935&partnerID=8YFLogxK
U2 - 10.1016/j.cplett.2006.09.092
DO - 10.1016/j.cplett.2006.09.092
M3 - Article
AN - SCOPUS:33750633935
SN - 0009-2614
VL - 431
SP - 404
EP - 409
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 4-6
ER -