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 FilmPolyvinyl Alcohol Film in 2 ppm malachite greenPolyvinyl Alcohol Film in 8 ppm malachite greenPolyvinyl Alcohol Film in 80 ppm malachite greenPolyvinyl Alcohol Film in 200 ppm malachite greenPVA-sodium montmorillonite filmPVA-sodium montmorillonite film in 2 ppm malachite greenPVA-sodium montmorillonite film in 8 ppm malachite greenPVA-sodium montmorillonite film in 80 ppm malachite greenPVA-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+ CentrifufgeCentrifuge settingsSH-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
Project name
Main project page
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