In this paper, the use of in situ Raman spectroscopy together with a novel multivariate data analysis method, band‐target entropy minimization (BTEM), is discussed to monitor the solution polymerization of methacrylamide in aqueous medium. Although FTIR spectroscopy is a more popular spectroscopic technique for polymer characterization and in situ polymerization monitoring, Raman spectroscopy is selected over FTIR in the current study. This is because water has very strong and broad infrared absorption bands and thus masks most of the other infrared signals contributed from monomer and polymer. On the contrary, water has very weak Raman scattering and thus it does not interfere the other Raman signals. The polymerization was initiated with potassium persulfate (KPS). A series of experiments were carried out varying initial monomer concentration, initial KPS concentration, and polymerization temperature. In situ Raman spectroscopy was used to monitor the polymerizing mixture and measure the compositions. The collected reaction spectra were subjected to BTEM to elucidate the pure component spectra, and then determine the conversion of monomer. The conversion data was then used to obtain kinetic parameters for the polymerization. The rate of consumption of monomers was found to follow the expression R = keff [I]0.55[M]1.41. The activation energy of the system was estimated at 121 kJ/mol. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5697–5704, 2007

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A new format of polymer support having cross-linked polymeric micro- and nanoarrays has been fabricated via reactive reversal nanoimprint lithography. Reactive reversal nanoimprint lithography is a relatively simple method to imprint highly cross-linked and chemically tunable polymers. An array of chloromethyl-functionalized cross-linked polystyrene has been imprinted on hard (silicon) and soft (polymer) substrates, and a model esterification reaction is demonstrated. The imprints have been found to be relatively stable under both static and dynamic stability tests carried out in various organic solvents. The chemical functionality is evenly distributed over the imprinted array. This method of fabricating polymer supports offers a high degree of freedom in terms of the choice of chemical functionality, the types of polymer matrix, and the size of the polymer support. The functional polymer support has potential applications for chemical and biological assays.

Synthesis of α-Amino Acids. -The disappointing results obtained with title compound (Ia) are explained by a rigid transition state formed through hydrogen bonding and π-stacking in which the substrate is completely shielded by picene and cinchonidine moieties. -(ELANGO*, S.; VENUGOPAL, M.; SURESH, P. S.; ENI; Tetrahedron 61 (2005) 6, 1443-1447; Inst. Chem. Eng. Sci., Jurong Island 627833, Singapore; Eng.) -Nuesgen 23-036