The H-bonding of carbonyl groups on a series of methacrylate polymers with silanols on fumed silica was studied with transmission FTIR. The set included poly(alkyl methacrylates) with alkyl groups, (n-C n H 2nþ1 ) of n ¼ 1, 2, 4, and 12 and poly(benzyl methacrylate). Shifts in the vibrational frequencies for bound carbonyl groups (of $20 cm À1 lower than those found in the bulk) were observed in the adsorbed polymer samples. A series of samples with different adsorbed amounts (varying from 0.5 to 2.0 mg m À2 ) of each polymer was prepared to determine the effect of the side chain on the H-bonding. The fractions of bound carbonyls, p, for each of the methacrylate polymers studied, were calculated from a model based on the ratios of the absorption coefficients of the bound to free carbonyl resonances,The X values were determined from linear regressions of the ratios of the free to bound carbonyl intensities as a function of the amounts of adsorbed polymer, M t . The bound fractions, p, were observed to decrease with increase in adsorbed amounts and with increase in the lengths of the side chains of the methacrylate polymers, except for poly(lauryl methacrylate) (PLMA). PLMA has a very low glass transition temperature (T g ) and is likely rubbery on the surface, whereas the other polymers are likely glassy at ambient temperature.

Implementation of hands-on pedagogies in the sciences and engineering is usually assessed during and immediately after implementation while studies investigating the effect of treatments on long-term retention of concepts are scarce. This work aims to discover the long-term retention of fluid mechanics concepts using a treatment that employs desktop learning modules (DLMs) with cartridges for a venturi meter and for energy losses in a straight pipe and 180° bend. Interviews 4-6 months after students took the fluid mechanics course offer insight into metacognitive processes and conceptual retention from the course. Questions in the interviews are those developed as part of a previous study investigating persistence of conceptual difficulties for students who have already had a fluid mechanics course. When we compare the two sets of interviews we anticipate results will show greater metacognitive skills and retention in understanding of fluid mechanics concepts for students that had the DLM treatment.

No abstract