@article{gorman_petrie_genzer_2008, title={Effect of substrate geometry on polymer molecular weight and polydispersity during surface-initiated polymerization}, volume={41}, ISSN={["1520-5835"]}, DOI={10.1021/ma8004857}, abstractNote={Poly(methyl methacrylate) (PMMA) anchored chains were grown on porous silicon (p-Si) and anodically etched aluminum oxide (AAO) substrates via surface-initiated atom transfer radical polymerization (ATRP). Using hydrogen fluoride, the chains could be cleaved from the substrates, as evidenced by infrared spectroscopy. The molecular weights and molecular weight distributions of PMMA could be analyzed directly on these substrates (after cleaving the chains from the support) using direct ionization mass spectrometry (DIOS-MS) and matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). Two principal conclusions were drawn from the study. First, matrix-free DIOS-MS was effective at direct analysis of the polymers up to a molecular weight of ≈6 kDa; the signal-to-noise ratio for heavier polymer chains diminished rapidly. Second, under the same polymerization conditions, PMMA grown on both p-Si and AAO substrates had a much lower molecular weight and a broader molecular weight distribution than ...}, number={13}, journal={MACROMOLECULES}, author={Gorman, Christopher B. and Petrie, Randall J. and Genzer, Jan}, year={2008}, month={Jul}, pages={4856–4865} }
 @article{petrie_bailey_gorman_genzer_2004, title={Fast directed motion of "Fakir" droplets}, volume={20}, ISSN={["0743-7463"]}, DOI={10.1021/la048612a}, abstractNote={In this Letter, we report on the motion of water droplets on surfaces decorated with molecular gradients comprising semifluorinated (SF) organosilanes. SF molecular gradients deposited on flat silica substrates facilitate faster motion of water droplets relative to the specimens covered with an analogous hydrocarbon gradient. Further increase in the drop speed is achieved by advancing it along porous substrates coated with the SF wettability gradients. The results of our experiments are in quantitative agreement with a simple scaling theory that describes the faster liquid motion in terms of reduced friction at the liquid/substrate interface.}, number={23}, journal={LANGMUIR}, author={Petrie, RJ and Bailey, T and Gorman, CB and Genzer, J}, year={2004}, month={Nov}, pages={9893–9896} }
 @article{chasse_sachdeva_li_li_petrie_gorman_2003, title={Structural effects on encapsulation as probed in redox-active core dendrimer isomers}, volume={125}, ISSN={["0002-7863"]}, DOI={10.1021/ja035515f}, abstractNote={Three pairs of isomeric, iron-sulfur core dendrimers were prepared. Each isomer pair was distinguished by a 3,5-aromatic substitution pattern (extended) versus 2,6-aromatic substitution pattern (backfolded). Several observations were made that supported the hypothesis that the iron-sulfur cluster cores were encapsulated more effectively in the backfolded isomers as compared to their extended isomeric counterparts. The backfolded isomers were more difficult to reduce electrochemically, consistent with encapsulation in a more hydrophobic microenvironment. Furthermore, heterogeneous electron-transfer rates for the backfolded molecules were attenuated compared to the extended molecules. From diffusion measurements obtained by pulsed field gradient spin-echo NMR and chronoamperometry, the backfolded dendrimers were found to be smaller than the extended dendrimers. Comparison of longitudinal proton relaxation (T(1)) values also indicated a smaller, more compact dendrimer conformation for the backfolded architectures. These findings indicated that the dendrimer size was not the major factor in determining electron-transfer rate attenuation. Instead, the effective electron-transfer distance, as determined by the relative core position and mobility in a dendrimer, is most relevant for encapsulation.}, number={27}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={Chasse, TL and Sachdeva, R and Li, C and Li, ZM and Petrie, RJ and Gorman, CB}, year={2003}, month={Jul}, pages={8250–8254} }