Effect of diluent

FIGURE 10-68 Schematic diagram depicting the amorphous region between lamellar molecules. 

FIGURE 10-69 Schematic diagram depicting a polymer in the presence of a solvent or plasticizer. 

FIGURE 10-71 Schematic plots of temperature versus specific heat for a two phase system (top) and a single phase (bottom). 

There are various equations, ultimately j derived from thermodynamic arguments, that describe the relationship between composition and the T. The most widely used is attributed to Fox33 (Equation 10-53)  

71 The plasticizer also migrates out of the polymer over time, evaporating into the air and condensing on the inside of your windshield in the form of a nice yellow guide. The T of your vinyl seat material thus increases, it becomes more brittle and eventually tears under the weight of your bum  

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J Hasa, J Janacek. Effect of diluent content during polymerization on equilibrium deformational behavior and structural parameters of polymer network. J Polym Sci Part C 16 317-328, 1967. 

Effect of diluent on deposition rate of nickel at 50 torr total pressure. [Reprinted with permission from AlChE J., 13 (86), 1967.]... 

Dimerisation is highly exothermic, the rate increasing rapidly with temperature, and may cause rupture of a closed uncooled container. The monomer may largely be prevented from dimerising by storage at — 80°C or below [1]. The polymerisation of the undiluted diene may become explosive within the range 0-40°C and at pressures above 2300 bar. The effect of diluents was also studied [2], A polymerisation was... 

Figure 4. The effect of diluent on the peak time in the Photo-DSC for HEMA polymerization.

In conclusion, we have shown that a simple, fast, electrochemical measurement, the open circuit potential, can be extremely useful in assessing the effect of diluent for high nitrile photocured coatings. Further work is underway to elucidate the underlying reasons behind the temperature induced changes observed in corrosion performance. 

Diluent added during crosslinking has two main effects it Increases the population of elastically Inactive cycles and it weakens the interchain constraints. Studies of poly(oxypropylene) triol-diisocyanate networks in the presence of diluent have shown that the effect of diluent on the equilibrium modulus is much stronger than would correspond to the effect of cycles (Figure 10) (32) which again corroborates the concept of permanent interchain constraints. 

Cohen and Reiss also considered a system in the form of a ring, end effects in a linear chain, the effect of diluents, and the generating function for particle survival, but these will not be given here. To the author s knowledge, however, the reversible process has not been solved. 

The effect of diluent content on the combustion process of both low and high density samples was studied at 0.1 MPa of nitrogen gas. The results demonstrate that for both low and high density samples the percent conversion of Ti to TiN increased linearly with increasing diluent content (Figure 11.4). 

Effect of Diluents and the Diluent-Induced Secondary Relaxation. 146... 

P. R. V. Rao, R. Dhamodaran, T. G. Srinivasan, and C. K. Mathews. The effect of diluent on 3rd phase-formation in thorium nitrate-TBP system - some novel empirical correlations. Solvent Extr. Ion Exch., ll(4) 645-662, 1993. 

Smulek, W. and Lada, W. A., Separation of alkali and alkaline earth metals by polyethers using extraction chromatography. Effect of diluent, J. Radioanal. Chem., 50, 169-178, 1979. 

The line-decomposition analysis of the equilibrium spectrum of the a-meth-ylene carbon was carried out using the elementary line shapes thus obtained for the three phases. The result is shown in Fig. 24. The composite curve of the decomposed components reproduces well the experimentally observed spectrum. The mass fraction of the crystalline component was estimated as 0.60 that is described in the figure. Based on the heat of fusion of 8.13 KJ/mol of this sample and the value of 14.2 KJ/mol for the crystalline material of this polymer the crystalline fraction was estimated to be 0.57. Here the heat of fusion for the crystalline material was obtained from the effect of diluent on the melting temperature with use of the relationship developed by Flory [91 ]. The crystalline fraction estimated from the NMR analysis is in good accord with the value estimated from the heat of fusion, supporting the rationality of the NMR analysis. 

Table I. Effect of Diluents on Flammable Limits of Some Gases...

The effect of diluents on the extraction of U02(TTA)2 B was studied10,83 87 and the adduct composition was reported to remain unaltered with change in diluent. However, the diluents have marked influence on the equilibrium constants as can be seen from the data given in Table 8. Attempts were made83 to determine diluent-free equilibrium constants by determining the activities of the solutes in different diluents. 

EFFECT OF DILUENT AND THERMAL TREATMENT ON POLYMER MORPHOLOGY, THERMAL STABILITY AND CHROMATOGRAPHIC PERFORMANCE OF MIPs USING L-PA AS TEMPLATE... 

Effect of Diluents on tbe Mechanical Properties of Amorphous Polymers ... 

The effect of diluents on the viscoelastic behavior of amorphous polymers is more complex at temperatures below T, i.e., in the range of secondary relaxation processes. Mechanical, dielectric and NMR measurements have been performed to study the molecular mobility of polymer-diluent systems in this temperature range (see e.g. From extensive studies on polymers such as polycarbonate, polysulfone and polyvinylchloride, it is well known that diluents may suppress secondary relaxation processes. Because of the resulting increase in stiffness, these diluents are called antiplasticizers . Jackson and Caldwell have discussed characteristic properties... 

Effect of Diluents on the Mechanical Properties of Glassy Polymers at High Strains... 

Another interesting feature of the AMO photocatalysts is the effect of diluent substrates such as MgO or activated C. Addition of substrates causes an increase in the rate of photoassisted catalytic oxidation of isopropanol. A synergistic effect is clear specific amounts of diluent lead to an increase. Too much or too little diluent leads to a decrease in rate. The exact explanation of this synergistic effect is not known, however, it may related to the ability of species such as OH or adsorbed hydrocarbons and intermediates to travel back and forth across the AMO/substrate interface. There does not seem to be a correlation of rate with the surface area, acid base character, particle size or other physical/chemical properties of the substrate. 

Fig. 20a illustrates the pronounced effect of diluent on 1ST). These data for dibenzyl ether solutions of polystyrene are typical of many pol5nner-diluent combinations. The intersecting straight lines represent the data for pure polymer corrected for the effects on so that... 

It is possible, however, to correct isothermal data to constant friction factor if the viscosity-temperature dependence is known at each ( )- Thus, Fig. 20b shows calculated from tjr according to Eq. (2.30) using the empirical dependence of and on (here Z is constant and 0.1 q) 1.0). Two regions can be clrarly discerned, one with slope 3.4, the other with slope 1.0. Moreover, the solid curve represents the empirical relation found for pure polymer as a function of X. Thus, the observation that the effect of diluent can be accounted for by the inclusion of q> in the definition for X given in Eq. (2.6) is verified. 

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