Interfacial Polymer Reactions Jeffrey T. Koberstein, Columbia University, DMR 0704054

1. Interfacial Polymer ReactionsJeffrey T. Koberstein, Columbia University, DMR 0704054 Attenuated Total Reflection Infrared Spectroscopy (ATR-IR) provided the first direct measurements of reaction rates for end functional polymers coupling to a substrate modified with functional self assembled monolayers (SAMS). The absorbance of the azide group on the SAM is monitored to measure the click reaction rate with alkyne groups terminating the polymer chains. We first learned how to form azide SAMs on germanium ATR crystals (Langmuir, 2012, 28, 486–493.). The surface reaction rates of end-functional polystyrene and poly(n-butyl acrylate) show two regions of behavior at low MW agreeing well with theoretical predictions (i.e., t1/2 and log t dependence). At higher MW, a third region where rate accelerates is observed. It is not predicted by theory, but was found by Penn et al. using indirect methods. Surface coverage of PnBA vs reaction time

2. Interfacial Polymer ReactionsJeffrey T. Koberstein, Columbia University, DMR 0704054 The PI sponsors 5-10 undergraduate research projects each semester and is hosting a number of summer scholars working on this NSF project: 2 high school students, 2 undergraduates and a professor from Tuoro College of Pharmacy in Harlem, NY. At top left is Karen Nan, a Columbia Chemistry undergraduate whose summer stipend is paid by the grant, and is working on melt interfacial reactions. Top center is Shuo Zhang, the PhD student working on the grant, and top right is Kellie Heom, a high school student working on simulations of polymer brushes. The bottom slide shows Xin Jun (left), a Columbia chemical engineering undergraduate and Nima Akhavein (righjt), a Tuoro professor. They are working on interfacial reactions on nanoparticles