User:Mary Mendoza/Notebook/CHEM 581: Experimental Chemistry I/2014/09/17

Project name

Main project page Previous entry      Next entry

Collection of DSC data Jacob Esenther extracted the DSC data from the Qseries interface, TA Universal Analysis. The data was compiled in a table below: PVA Conc. (ppm) ' Energy (J/g) H₂0 (mg) Glass Transition (⁰C) Water Evaporation Peak (⁰C) 2 928.4 1.3239 69.11 and 79.8 108.58 8 1001 1.9796 68.77 99.31 80 1340 2.9384 68.338 105.91 200 819.4 1.0803 68.63 128.77 Control 582.9 0.95407 68.566 125.61 PVA-Clay 2 1303 1.8931 68.716 100.97 8 883.8 1.4585 68.644 99.59 80 861.3 2.2633 68.866 102.05, 106.55, and 128.44 200 N/A N/A N/A N/A Control 671.2 0.90296 69.164 116.15 and 105.16 James Schwabacher prepared the following graphs from the DSC: Polyvinyl Alcohol Film Polyvinyl Alcohol Film in 2 ppm malachite green Polyvinyl Alcohol Film in 8 ppm malachite green Polyvinyl Alcohol Film in 80 ppm malachite green Polyvinyl Alcohol Film in 200 ppm malachite green PVA-sodium montmorillonite film PVA-sodium montmorillonite film in 2 ppm malachite green PVA-sodium montmorillonite film in 8 ppm malachite green PVA-sodium montmorillonite film in 80 ppm malachite green PVA-sodium montmorillonite film in 200 ppm malachite green A closer look of the PVA-sodium montmorillonite film indicates that there is no defined glass transition as shown below: PVA-sodium montmorillonite film in 200 ppm malachite green; no defined glass transtion curves UV-Vis of MG-PVA samples Table 1. Absorbance of Polyvinyl Alcohol Films in Malachite Green Using quartz cuvettes, absorbance of 2 mL malachite green samples were collected. 80 and 200 ppm malachite green samples were diluted to 100x and 50x, respectively. The absorbance of each sample are listed on table 1. Absorbance Spectra of PVA films in Malachite Green Centrifuge of Ionic Liquid Exchange Clay In the original protocol, the instruction called for vacuum filtration of our mixture, tributylhexadecylphosphonium bromide, through a 0.2μm nylon fiber. A consensual decision was made that placing the mixtures in centrifuge would provide better results of separation. The sample weighed the amount of 17.69 g. Addition of water was made to balance the viscous mixture, (1-hexadecyl)triphenylphosphonium bromide), from Eleni's group. The final weight was 27.42 g. The mixture was centrifuged for 30 minutes at 4000 rpm, 4°C. The centrifuge used was the make of Thermo Scientific Sorvall RC 6+ Centrifufge. The rotor chosen to perform the centrifuge was SH-3000 4700 max. Thermo Scientific Sorvall RC 6+ Centrifufge Centrifuge settings SH-3000 4700 max rotor At 10:53 AM, samples were observed to have three distinct layers; top and bottom layer were clay, and the middle was composed of water/supernatant. The supernatant was collected and transferred into a 50 mL falcon tube. This was stored if additional analysis was needed in the future. Two sets of washes are required for the exchanged clay. Each wash comprised of washing the clay with water to remove adsorbed NaCl and ethanol to remove remaining surfactants. After the washes were completed by Dr. Hartings, the mixture was stored in an oven to evaporate excess water. Powder X-RAY Diffraction of MG-PVA-clay samples Eleni Kalivas executed the introduction of the usage of the powder X-RAY diffraction instrument. The make of the instrument is by Rigaku MiniFlex II. The parameters set for the data collection made via the Standard Measurement interface are as follows: 2° start angle 40° stop angle 0.5 inch sampling width 1°/minute scanning speed The original protocol stated a 1°/second scanning speed Our group provided the blank PVA film which was placed in position 4. Other groups' PVA films were placed in the following order: Position 1: Dr. Hartings' solid, sodium montmorillonite Position 2: 8 ppm MG from Madeleine and Alicia Position 3: group's 2 ppm MG Position 5: 80 ppm MG from Melvin, Eleni, and Becca Position 6: 200 ppm MG from Andrew, Michael, and Tami Completion of Exfoliated Clay Film Synthesis This was performed by our group member, Jacob Esenther, following the Completion of Film Synthesis protocol from August 29, 2014.