For a polymer film deposited on a surface, the strength of the surfacesegment interaction affects the mobility of polymer-chain segments. The selfconsistent field lattice model of Scheutjens and Fleer,1 based on mean-field lattice models of polymer at interfaces,2 has been used to describe the distribution of conformations of polymers on surfaces. Adsorbed-polymer segments may be classified as belonging to loops, trains or tails. There are different techniques used to study the molecular motion of the polymer including modulated differential scanning calorimetry (MDSC)3 and nuclear magnetic resonance (NMR).4,5 in this work, solid-state deuterium (2H) NMR was used to characterize the polymer segmental motions. Solid-state 2H NMR is an excellent tool for studying segmental dynamics. The interpretation of solid-state 2H NMR spectra of a deuterium-labeled polymer can provide valuable information on the molecular motion and the physical properties of the polymer.6,7 Relatively narrow polydispersity poly(isopropyl acrylate)-d7 (PIPA-d7) has been studied using deuterium NMR. PIPA has two methyl groups, branched at a methine carbon atom. Substitution of deuterons onto these methyl groups provides a different probe for the segment mobility than that used in previous studies.7-9 the structure of the side chains of PIPA-d7 is different than that of poly(methyl acrylate) previously studied. Bulk and surface-adsorbed PIPA-d7 polymers were investigated using the 2H quadrupole-echo NMR technique as a function of temperature.
P. Krisanangkura and F. D. Blum, "Segmental Dynamics of Poly(Isopropyl Acrylate)-d7 on Silica," Polymer Preprints, American Chemical Society (ACS), Jan 2006.
National Science Foundation (U.S.)
Keywords and Phrases
Chain Mobility; Deuterium NMR; Modulated Differential Scanning Calorimetry; Nuclear Magnetic Resonance; Polymer-Chain Segments; Surface-Segment Interaction
Article - Journal
© 2006 American Chemical Society (ACS), All rights reserved.
01 Jan 2006