Copolymerization plot

Figure 4. Copolymerization plot for acrylamide and N-isopropyl acrylamide (NIPAAM).

Fig. 16 Ratios of monomer to solvent ([M]/[DMAc]) obtained by GC for t = 0 samples of the different copolymerizations plotted against fraction of the second monomer (f) EtOx NonOx (a), MeOx NonOx (b), MeOx EtOx (c). These graphs clearly demonstrate the gradual change in monomer composition within the investigated library. (Reprinted with permission from [88]. Copyright (2006) American Chemical Society)...

In the hypothetical case when fi = t2 = 1, none of the two macroradicals differentiates between the monomers, and the composition of the copolymer equals that of the monomer mixture at any degree of conversion (the so-caUed azeotropic mixture of comonomers). Only in this particular case (line 5) is the distribution of the monomers in the macromolecule formed close to statistical. When q < 1 and f2 < 1, radical —m tends to react with monomer M2, whereas radical — reacts more rapidly with monomer Mj. This tendency to alternation of the monomer units mi and m2 in the growing chain results, among others, in the predominant consumption of the minor component at the beginning of copolymerization (plot 3). The deviation from azeotropic copolymerization is also pronounced in the case of = T2 < 1 (plot 4). However, if the starting mixture contains both comonomers in equal... 

Keeping the composition of copolymerization media constant the total comonomer concentration of which is varied. The absorbed dose was kept constant at 0.14 KGy for the AM-AANa and at 0.35 KGy for the AM-DAEA-HCl systems. The results are shown in Figs. 4 and 5, which show the rate of polymerization, Rp, the degree of polymerization, and the intrinsic viscosity increase with increasing monomer concentration. At comonomer concentration >2.1 M/L, DPn decreases with increasing comonomer concentration. From the logarithmic plots, exponents of the comonomer concentration for the AM-AANa system were determined to be [17,54]. 

From the logarithmic plot of the Arrhenius equation shown in Figs. 8 and 9, the overall activation energy, / p, was calculated to be 0.65 and 0.56 Kcal/mol for AM-AANa and AM-DAEA-HCl systems, respectively. However, the corresponding reported values for gamma radiation induced copolymerization of acrylamide with DMAEM-MC in aqueous solution was found to be 2.0 Kcal/mol [16]. 

Fig. 3. Mark-Houwink plot (a) and contraction factors (b),g =[ j]b,a ched/[ lliineaD as a function of the molecular weight for the copolymerization of the methacrylate-type inimer 12 with MMA under different comonomer ratios, y=[MMA]o/[12](,=1.2 (+), 5.2 (0), 9.8 (V), 26 (A), 46.8 (0),86.5 ( ),respectively.TheintrinsicviscositiesofPMMA(—) are given for comparison. (Reproduced with permission from [28]. Copyright 2001 American Chemical Society.)...

Fig. 24.—Incremental polymer composition (mole fraction Fi) plotted against the monomer composition (mole fraction/i) for ideal copolymerizations (ri — X/r F). Values of r are indicated.

Fig. 27.—The rate of copolymerization of styrene and methyl methacrylate at 60°C in the presence of azo-bis-isobutyronitrile (1 g./l.) plotted against the mole fraction of styrene. Broken line has been calculated from Eq. (26) assuming < = 1. Solid line represents calculated curve for 0 = 13. (Walling. q...

Fig. 137.—Equilibrium swelling ratio qm of poly-(methacrylic acid) gels prepared by copolymerizing methacrylic acid with 1, 2, and 4 percent (upper, middle, and lower curves, respectively) of divinylbenzene plotted against degree of neutralization i with sodium hydroxide. (Katchalsky, Lifson, and Eisenberg. )...

First, it was necessary to determine the position of the maxima on the plots of TBSM — MA copolymerization rate vs. composition of the monomer mixture at various total monomer concentrations. The observed shift of the maxima of the rate as a function of the dilution of the monomer mixture toward higher MA concentrations is a consequence of a complex mechanism, i. e. both free and com-... 

The values of K and (3(K > 0 and 0 < P < 1) were calculated for each monomer pair from the logarithmic plot of the ratio of the monomers in the monomer feed [MJ/[M2] to the comonomer units in the copolymer using a modified equation of binary copolymerization ... 

The activation energy (Ea) of the migration copolymerization of (n-C4H9)2SnH2 with (I) calculated from the plot of the rate constant vs. temperature is 12.2 kcal/mol. 

Quantitative polymerizations of butadiene and copolymerizations of butadiene with styrene to high molecular weight polymers have been obtained. Plots of In (M0/Mt)versus time are linear, indicating a first order dependence on monomer. 

Figure 7. Log-log plots of the conversion curves of the copolymerization of acrylic acid with methacrylic acid (. Mol % acrylic acid in the mixture (1) 0% (2) 23.5% (3) 45.5% (6) 71% (8) 83.2% (9) 86% (11) 100%. The copolymer formed in a mixture of 75 mol % acrylic acid contains 50% acrylic acid and 50%...

The plots in Fig. 6-2 illustrate an interesting characteristic of copolymerizations with a tendency toward alternation. For values of r and r2 both less than unity, the F /f plots cross the line representing F — j. At these interesections or crossover points the copolymer and feed compositions are the same and copolymerization occurs without a change in the feed composition. Such copolymerizations are termed azeotropic copolymerizations. The condition under which azeotropic copolymerization occurs, obtained by combination of Eq. 6-12 with d[Mi]/ii[M2] = [Mi]/[M2], is... 

One can show the drift of copolymer composition with conversion for various comonomer feed compositions by a three-dimensional plot such as that in Fig. 6-4 for the radical copolymerization of styrene (M, )-2-vinylthiophene (M2). This is an ideal copolymerization with r — 0.35 and r-L — 3.10. The greater reactivity of the 2-vinylthiophene results in its being incorporated preferentially into the first-formed copolymer. As the reaction proceeds, the feed and therefore the copolymer become progressivley enriched in styrene. This is shown by Fig. 6-5, which describes the distribution of copolymer compositions at 100% conversion for several different initial feeds. 

The values of v and u for a monomer are obtained from monomer reactivity ratios for copolymerization of that monomer with a series of reference monomers. A plot of the data according to Eq. 6-60a as [log r 2 — log ns] versus 71] yields a straight line whose slope is u2 and intercept on the y-axis is —v2. 

Figures 6-12 and 6-13 shows plots of copolymer composition and propagation rate constant, respectively, versus comonomer feed composition for styrene-diethyl fumarate copolymerization at 40°C with AIBN [Ma et al., 2001]. The system follows well the implicit penultimate model. The copolymer composition data follow the terminal model within experimental error, which is less than 2% in this system. The propagation rate constant shows a penultimate effect, and the results conform well to the implicit penultimate model with si = 0.055, S2 — 0.32.

Fig. 6-12 Plot of Fi versus/i for copolymerization of styrene (MJ and diethyl fumarate (M2). The solid line represents the terminal model with r — 0.22, r2 — 0.021. After Ma et al. [2001] (by permission of American Chemical Society, Washington, DC) an original plot, from which this figure was drawn, was kindly supplied by Dr. T. Fukuda.

Fig. 6-14 Effect of depropagation on copolymer comosition in the anionic copolymerization of vinylmesitylene (MJ-a-methylstyrene (M2) at 0°C for/2 constant at 0.91. The dashed-line plots are the calculated curves for Lowry s cases I and II (with r = 0.20 and r2 = 0.72) the experimental data follow the solid-line curve. After Ivin and Spensley [1967] (by permission of Marcel Dekker, New York).

Using the r and tz values from Table 6-2, construct plots showing the initial copolymer composition as a function of the comonomer feed composition for the radical copolymerizations of methyl acrylate-methyl methacrylate and styrene-maleic anhydride. Are these examples of ideal or alternating copolymerization ... 

The dependence of the composition of the copolymer on the proportions of the monomers in the initial mixture can be portrayed graphically in a so-called copolymerization diagram (Fig. 3.4). The mole fraction of one of the two monomeric units in the resulting copolymer is plotted against the mole fraction of this monomer in the original reaction mixture the curve can also be calculated from the reactivity ratios by means of Eq. 3.18. 

Figure 5. YBR plot for the copolymerization of 3-oximino-2-butanone methyl methacrylate and methyl methacrylate obtained from Raman data.

Consistent with the PMCN homopol3nner results above, the MCN copolymers of Table VI exhibit PE etch rates intermediate to those of the two respective homopolymer values. When MCN is copolymerized with MCA, the resulting copolymers etch faster than PMCN and slower than PMCA (see Table VI). The etch rate is approximately linear with mole % MCA content this data Is plotted in Figure 2. 

As mentioned in Chapter 2, if two comonomers are not connected with the template by covalent bonds, reactivity ratios can be calculated on the basis similar to the conventional copolymerization. The only difference is that reactivity ratios ri and T2 for both monomers depend on the concentration of the template. In order to compare experimental data with these considerations, copolymerization of methacrylic acid with styrene was carried out in the presence of PEG (mol. wt. 20,000) as the template. The reactivity ratios rf and r2 can be calculated according to the Kellen-Tiidos method. The results are shown in the Figure 5.4. According to this method, a proper functions of monomer mixture composition, R, and copolymer composition, E, were plotted ... 

Figure 5.4. Kellen-Ttidos plot for calculation of reactivity ratios from composition of monomer mixture, R, and composition of copolymer, E Copolymerization of methacrylic acid with methyl methacrylate in the presence of PEG 20,000. Reprinted from S.PolowinskijEnr.PoZym.t/., 19,679 (1983) with kind permission from Elsevier Science Ltd.

In the copolymerization of EO and PS with (NMTPP)ZnSPr in benzene in the dark at room temperature ([EO]o/[PS]o/[(NMTPP)ZnSPr]o=50/50/l), the consumptions of EO and PS took place rather slowly (25 and 80%, respectively, in 30 h), while both were accelerated by elevating the temperature to 70 °C (18 and 85% in 1 h) or irradiation with visible light (57 and 70% in 5.3 h). The consumptions of EO under the three different conditions are plotted against those of PS in Fig. 51, which demonstrates that the relative consumption of EO to PS in the dark at room temperature ( ) is far from unity. This tendency is unchanged under accelerating conditions by elevating the temperature to 70 °C in the dark ( ). However, of particular interest is that the rates of consumption of the two comonomers come closer to each other under irradiation with visible light (O). 

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