Swelling curve linear

Effect of CaCOs addition to NR on the swelling ratio and results showed that swelling curves exhibit a linear portion followed by a plateau region at longer time and the results seemed to be nearly dependent on the rubber matrix due to... 

Figure 3.52. Phase separation region of the system (linear polystyrene)+cyclohexane for a finite molecular mass of polystyrene ), at M -> oc (i ), (C are critical points, dashed lines cire spinodals)., Swelling curves of (network poly.slyrene)- -cyclohexane with an increasing density of crosslinks ui < i 2 < hage, 1977) [Reprinted with permission from G.Rchagc. Bcrichtc der Bunsengeselsehaft Phys. Chem. 81 (1977) 969 979. Copyright 1977 by Steinkopft Piihli.slier.s Danistedt]...

Fig. 5 now shows a typical, rather linear swelling curve for the alloy NbTo,59. Only the initial slope is used for data analysis. Table 1 shows the values for (v g/J2), v g and the pressures p extracted from our swelling curves. Thus, He requires roughly half of an atomic volume when it is located in the present bubbles. The pressures obtained lie in the range 5 to 10 GPa which is close to the threshold pressure required for loop punching ... 

We suggest that the rapid process corresponds to hole-filling and/or adsorption onto surfaces, and that the slow process, which follows first-order behavior, corresponds to swelling of the coal extract. Extrapolation of the linear portion of the curves shown in Figures 10 and 11 to time zero should yield the total uptake of benzene attributed to swelling. The results of this analysis are summarized in Table IV, where the total benzene uptake, M , and the uptake attributed to the hole-filling/adsorption and the swelling processes, and M., are shown. 

Fig. 5. Linear swelling ratio calculated for neutral NIPA gels on the basis of the Flory-Rehner theory. The structural parameters used in the calculation were determined from the preparation condition of (a) gel A, and ( >) gel B. The curve (c) represents the critical transition. (Reproduced with permission from Ref 20)...

Fig. 7. Measured linear swelling ratio for ionized NIPA gels as functions of temperature. The curves have been replotted using the data reported in Ref. 7. The concentration of ionic species (SA) is shown in the figure...

Fig. 8. Linear swelling ratio calculated for ionized NIPA gels. Numbers on curves represent the effective number of charges per polymer chain. Structural parameters were calculated from the preparation condition of the samples. Other parameters were identical with those used in the calculations for neutral NIPA gels...

In Fig. 7.17, the dry modulus of various PDMS networks is plotted as a function of their equilibrium swelling in toluene. A single curve results for both model networks (open symbols) made by end-linking linear chains with two reactive ends and networks with intentionally introduced defects in the form of dangling ends (filled symbols) made by end-linking mixtures of chains with one and two reactive ends. The data are fit to Eq. (7.91) as the solid lines in Fig. 7.17 and their intersection determines the crossover concentration 0 = 0.2, which is typical for good solvents. 

Moreover, the curves of 2.0 and 5.0 phr TAC, have a more linear relationship compared with those crosslinked with DCP alone or in the presence of 0.5 phr TAC. This strongly suggested that at higher TAC concentrations, a more rigid network was present which restricted the ability of samples to swell. The results also give further evidence that gel content is not really a suitable parameter to evaluate solid properties when using TAC in the crosslinking system. 

Fig. 7.9. Contour curves for properties of PIB-PE-PW films, in terms of pseudocomponents, (a) Linear model for elongation, (b) Quadratic model for swelling. The desired characteristics are obtained for compositions similar to those of the 6 mixture (high elongation) and mixture 4 (low swelling).

The above expressions allow us to describe the shape of kinetic curves gi(t) in general terms. In particular, as it follows fromEqs. [6.1.39] - [6.1.41] atq< 1, the kinetic curves in the coordinates (t,gi) are upward convex and have the shape typical for pseudo-normal sorption. This takes place at slinear mode of liquid absorption. At s>Se/2-l the lower part of the kinetic curve is convex in a downward direction and the whole curve becomes S-shaped. Note that in terms of coordinates (t ,gi) at s > 0 all the kinetic curves are S-shaped. Hence, the obtained solutions enable one to describe different anomalies of sorption kinetics observed in the experiments on elastomer swelling in low-molecular liquids. 

The swelling law is a linear one with a slope of 0.48 which corresponds to a one-dimensional swelling, in contrast with the law expected for curves for a two- or three-dimensional swelling,... 

The temperature of volume phase transition of each cryogel depends on the nature of the polymer network. The Typt estimated as the maximum of the first derivative of the swelling versus temperature curve, of PNlPAAm, HPC, and PETEGA cryogels are 32, 48, and 33 °C, respectively. Most often, Typr is close to the lower critical solution temperature (LCST) of the linear polymer analog however, unlike it, the transition is not so sharp. 

Figure 5.49. I cmperature dependence of the. swelling factor Xo as given by the linear approximation of the tricritical effects Xo,t, by renormalization theory Xo, and by h lory s approximation Xo.f- the crosses are the experimental values from light scattering of PS solutions in cyclohexane (Perzynski, 1984) the dashed line is the theoretical curve after a shift of Xo to the right to obtain Xq =. Y = 1 at the same temperature (T = 35°C) (Diiplantier ct al., 1989) [Reprinted with permission from B.Duplanticr, G.Jannink, J. dcs Cloizeaux. I liys. Rev. I,ett. 56 (1986) 2080-2083. Copyright 1986 by the Anmeriean Physical Society]...

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