Chromatogram of PMMA

Figure 1. Mean height values of chromatograms of PMMA and 95% confidence value as a percent of mean vs, retention volume...

Figure 3. Gel permeation chromatograms of PMMA exposed to increasing doses of y radiation. High molecular weight fractions elute at low elution...

Figure 3. Baseline-adjusted chromatograms of PMMA fractions C, D, E, F, G, H, I, and J...

Figure 9.10 Comparison of typical gel permeation chromatograms of PMMA-g-PDMS copolymers produced by various methods (DeSimone...

Figure 9.14 Gel permeation chromatograms of PMMA-g-PDMS copolymer before and after extraction with supercritical carbon dioxide. GPC trace of extract (PDMS macromonomer) is shown, too (Hell-stern, 1989).

Fig. 17 A LCCC chromatograms of PtBMA-l7-PMMA. Precursor PMMA (Mj,=31.0 kg/mol) with different PtBMA block lengths (Mj =0,46.3,85.3 kg/ mol) at the critical condition of Pt-BMA. Column two Nucleosil C18 250x4 mm 300 A and 1,000 A. Eluent THF/CH3CN (49.5/50.5, w/w). B LCCC chromatograms of PMMA-block-PtBMA. Precursor PtBMA (Mj = 73.0 kg/mol) with different PMMA block lengths (Mj,=29.6, 108, 167 kg/mol) at the critical condition of PMMA. Column two Nucleosil 150x4 mm, 100 A and 250x4 mm, 300 A. Eluent THF/fj-hexane (82/18, w/w). Reproduced from [44] with permission...

Fig. 10. LC methods based on CEEC represented on chromatograms of PMMA eluted in different modes from silica gel column. Detector ELSD. The figure is constructed according to data published by Berek [57]. THE and toluene are thermodynamically good solvents for PMMA, herefore LC LCS is not possible in this system...

Fig. 11A-D. Chromatogram of PMMA 280 kDa injected in eluent the detected by A RI detector, B viscosimeter. Mobile phase MEK/cyclohexane. Column packing Silica gel. From [50] with permission. A chromatogram of polystyrene sample injected in dichloromethane detected by C UV, D ELSD. Mobile phase Dichloromethane/n-hexane. Column packing Silica gel [151]...

One possibility is that although averages for polystyrene standards require correction, those for PMMA would not According to symmetrical axial dispersion theory (5) the correction depends upon both the slope of the calibration curve (different for each polymer type) and the variance of the chromatogram of a truly monodisperse sample. Furthermore, the calibration curve to be utilized can be obtained from a broad standard as well as from monodisperse samples. The broad standard method may itself incorporate some axial dispersion correction depending upon how the standard was characterized. 

As previously mentioned, the results of this approach in the polymerization of PMMA have already been published and tested (e.g. 0). Also, a few workers have r ently begun to ro ognize some of the value of utilizing chromatogram heights (15, 1. ... 

B. Measurement of Property Distributions for Copolymers. Figure 12 shows chromatograms of typical products in the copolymerization study (Column Code B2). Since the detector is responding to concentration, composition, and periiaps sequence length, the direct single detector interpretation as described for PMMA is not immediately applicable here. Tacticity variation is yet another consideration but ]s assumed of sa ond order importance for th samples (22). 

Fig. 14 Size-exclusion chromatograms of standard PSs for monolith columns with and without the high-density PMMA brush (Mn = 15000, M /Mn = 1.2, a = 0.6 chains nm ) on an inner surface. The inset shows a cartoon illustrating the size exclusion mode by the brush...

Thus, MM A (50 equiv with respect to 1) was first polymerized with 1 in the presence of 3e (6 equiv) PMMA at 100% conversion, Mn=6500 [Mn j gQj. =5000], Mw/Mn=1.13 [Fig. 42 (I)], and then oxetane (150 equiv) was added to this system, whereupon the second-stage polymerization ensued and was complete within 14 h. The GPC chromatogram of the product [Fig. 42 (II)] clearly shifted towards the higher molecular-weight region, while retaining the narrow MWD (Mn=15,000 =11,000], Mw/Mn=1.20), The successful formation of the... 

Fig. 25. GPC chromatograms of a pMMA macroinitiator and a pMMA b-p4VP copolymer. Reaction conditions 40°C [4VP]0=4.62M [4VP]0/[pMMA-Cl]o=710 [pMMA-Cll]0/[Cu-Cl]0/[Me6TREN]o=l/2/2. Reprinted with permission from [198], Copyright (1999) American Chemical Society.

Figure 31 shows the GPC/NMR data of the isotactic PMMA with Mn of 12 600. The signals due to -OCH3, CH2, q-CH3 and r-C4H9 protons resonate at 3.60, 2.13 and 1.52, 1.20 and 0.86 ppm, respectively. All the cross-sections at the peak positions give 1H NMR-detected GPC chromatograms. The H NMR-detected GPC chromatograms of the three PMMA samples are shown... 

Figure 9.13 Cel permeation chromatogram of anionically prepared PMMA-g-PDMS copolymer (A) parent copolymer as prepared and (B) parent copolymer after Soxhiet extraction with hexane (Hellstern, 1989).

Figure 9.18 Gel permeation chromatograms of fractions of PMMA-g-PDMS copolymer fraction 1 obtained with supercritical carbon dioxide and fractions 2, 3, 4 obtained with supercritical chlorodifluoromethane (Hellstern, 1989).

Fig. 24. Chromatograms of PS-PMMA blands in different chromatographic modes, and critical diagram log molar mass vs retention time for PMMA upper right comer) stationary phase silica gd Si-100 mobile phase methylethylketone-cyclohexane. (From [53] with permission)...

Fig. 25, Chromatograms of PS-PMMA blends at the critical point of PS stationary phase RP-18 mobile phase THF-water 88.8 11.2 v/v...

Figure 3. The reverse phase HPLC chromatograms of the pMMA, polystyrene, p(Sty-b-MMA) mixture with ELS and UV detection.

Figure 5. The reverse phase HPLC chromatograms of the mixture of pMMA, pBA, p(MMA/BA) and p(BA-b-MMA) with ELS and UV detections. The SUPELCOSIL Octadecyl column (25cm x 4.6mm ID) was used with acetonitrile/THF solvent gradient (flow rate Iml/min).

FIGURE 16 Real chromatograms of model 4 1 blends of poly styrene and PMMA. Molar masses of narrow molar mass dispersity polymers were 270 and 293 kg mob, respectively. For detailed explanation, see the text. 

FIGURE 25 Comparison of SEC, LC LCD and 2D-LC real chromatograms of a typical commercial block copolymer PS-b-PMMA that contained parent homopolymers. For detailed explanation, see the text. 

Figure 46.16 contains the TIC chromatograms of the pyrolyzates at 400°C for pure PMMA and its nanocomposites. The major decomposition product is MMA monomer and the addition of T1O2 does not change the nature of decomposition products. However, as the weight% ofTi02 increases yield of methanol (miz = 32), propanoic acid methyl ester Qnlz = 88) and methacrylic acid (mIz = 86) also increase (Figure 46.17).The emitted quantities are lower when PMMA is loaded with micrometric particles rather than with nanoparticles, except for propanoic acid methyl ester. This behavior can be related to the precision of measurements as propanoic acid methyl ester is produced in much lower amounts than methanol or methacrylic acid.

FIGURE 11.3 Extracted ion chromatogram for 181 m/z. Analysis of PMMA from two different spots on the TLC plate. 

Fig.12A,B. LCCC chromatograms of blends of PMMA and PnBMA under the critical condition of PMMA. Column LiChrospher 300 A +1000 A, mobEe phase methyl ethyl ketone/cy-clohexane (72/28, v/v), detector A differential refractometer B capElary viscometer. The large injection solvent peak is suppressed in the chromatograms recorded by the viscosity detector.

Figure 21 HPLC/MS spectrum index plot of pMMA/BA copolymers. Mass spectra extracted from the total ion chromatogram show the progression from polymethyl methacrylate homopolymer (A) to polybutyl methacrylate homopolymer (F) in 20% butyl acrylate increments. 

Different liquid chromatography modes in polymer analysis were successfully interfaced with electrospray ionisation time-of-flight mass spectrometry in a single experimental set-up the mass spectrometry data from size exclusion chromatography/mass spectrometry of PMMA were used as absolute calibration points in the size exclusion chromatography/refractive index chromatogram, and monomer mass and end groups were inferred from the isotopically resolved mass spectra. 44 refs. 

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