Multicomponent polymers liquid systems

Torque rheometers are multipurpose instruments well suited for formulating multicomponent polymer systems, studying flow behavior, thermal sensitivity, shear sensitivity, batch compounding, and so on. The instrument is applicable to thermoplastics, rubber (compounding, cure, scorch tests), thermoset materials, and liquid materials. 

Koningsveld, R. Kleintjens, L.A., "Liquid-liquid Phase Separation in Multicomponent Polymer Systems. X. Concentration Dependence of the Pair-Interaction Parameter in the System Cyclohexane- Polystyrene," Macromolecules, 4, 637 (1971). 

Kleintjens, L. A. Koningsveld, R., "Liquid-Liquid Phase Separation in Multicomponent Polymer Systems. XIX. Mean-Field Lattice-Gas Treatment of the System n-alkane/linear-poly-ethylene," Coll. Polym. Sci., 258, 711 (1980). 

Finally, it is worth mentioning that the linear relationship between H and Tg has been derived only from one-phase systems (amorphous homo- and copolymers. Table 3.2). However, it can be applied to explain the micromechanical behaviour of multicomponent or multiphase systems containing at least one liquid-like component or phase (see Chapter 5). Another peculiarity of the polymers listed in Table 3.2 is that their main chains comprise only single C-C, C-0 or C-N bonds... 

These three approaches have found widespread application to a large variety of systems and equilibria types ranging from vapor-liquid equilibria for binary and multicomponent polymer solutions, blends, and copolymers, liquid-liquid equilibria for polymer solutions and blends, solid-liquid-liquid equilibria, and solubility of gases in polymers, to mention only a few. In some cases, the results are purely predictive in others interaction parameters are required and the models are capable of correlating (describing) the experimental information. In Section 16.7, we attempt to summarize and comparatively discuss the performance of these three approaches. We attempt there, for reasons of completion, to discuss the performance of a few other (mostly) predictive models such as the group-contribution lattice fluid and the group-contribution Flory equations of state, which are not extensively discussed separately. 

Heil and Prausnitz proposed an FH/UNIQUAC-type model, which has been applied to a number of ternary liquid-liquid PS-mixed solvent systems. Satisfactory results were obtained for the ternary systems using solely two parameters per binary. These results show the potential of local composition concept (UNIQUAC, UNIFAC) for multicomponent polymer systems. The required binary parameters were estimated from solvent-polymer VLE data. 

Koningsveld.R., Kteintjens,L.A., Shultz, A. R. Liquid-liquid phase separation in multicomponent polymer solutions. IX. Concentration-depe ent pair interaction parameter from critical miscibility data on the system polystyrene-cyclohexane. J. Polymer Sd. A 2,8,1261 (1970). 

Koningsveld.R., Kleintjens.L.A. Liquid-liquid phase separation in multicomponent polymer systems. X. Concentration dependence of the pair-interaction parameter in the system tyclohexane/polystyrene. Macromole es 4,637(1971). 

Kambour RP, Bendler JT, Bopp RC (1983) Phase behavior of polystyrene, poly(2,6-dimethyl-l,4-phenylene oxide), and their brominated dtaivatives. Macromolecules 16 753-757 Koningsveld R, Kleijens LA (1971) Liquid-liquid phase separation in multicomponent polymer systems. X. Concentration dependence of the pair-interaction parameter in the system cyclohexane-polystyrene. Macromolecules 4 637-641 Maron SH (1959) A theory of the thermodynamic behavior of non-electrolyte solutions. J Polym Sci 38 329-342... 

This chapter summarizes the thermodynamics of multicomponent polymer systems, with special emphasis on polymer blends and mixtures. After a brief introduction of the relevant thermodynamic principles - laws of thermodynamics, definitions, and interrelations of thermodynamic variables and potentials - selected theories of liquid and polymer mixtures are provided Specifically, both lattice theories (such as the Hory-Huggins model. Equation of State theories, and the gas-lattice models) and ojf-lattice theories (such as the strong interaction model, heat of mixing approaches, and solubility parameter models) are discussed and compared. Model parameters are also tabulated for the each theory for common or representative polymer blends. In the second half of this chapter, the thermodynamics of phase separation are discussed, and experimental methods - for determining phase diagrams or for quantifying the theoretical model parameters - are mentioned. 

I. Koningsveld R., Kleintjens L.A., (1971) Liquid - Liquid phase separation in Multicomponent Polymer Systems X. Polystyrene-Cyclohexane, Macromolecules 4 627-SAX. 

Many of the polymers such as caprolactam, silicone, urethane, and polyester are multicomponent reactive liquids that may be molded by the reaction injection process which is particularly suitable for large area pieces such as auto body parts, furniture, and housing sections, because of the fast cycle and low mold clamp pressure requirement. This system greatly diminishes the capital investment requirement for such large parts. A 5000-ton conventional injection press is presently the largest and it costs 1,000,000. An automobile fender would need a 12,000 ton press costing 2,000,000 by the conventional injection process with reaction injection equipment cost might be one tenth of the machine cost for the older process. 

Lindvig, Th., Economou, I.G., Danner, R.R, Michelsen, M.L, and Kontogeorgis, G.M., 2004. Modeling of multicomponent vapour-liquid equilibria for polymer-solvent systems. Fluid Phase Equilib., 220 11-20. 

KL1 Kleintjens, L.A., Schoefferleer, H.M., and Domingo, L., Liquid-liquid phase separation in multicomponent polymer systems XIII. Quasi-binary phase diagrams with three-liquid-phase separation, Brit Polym. J., 8, 29,1976. 

Berek D. Separation of minor macromolecular constituents from multicomponent polymer systems by means of liquid chromatography under limiting conditions of enthalpic interactions. Eur Polym J 2009 45 1798-810. 

Kleintjens LA, Koningsveld R (1980) Liquid-liquid phase separation in multicomponent polymer systems XIX. Mean-field lattice-gas treatment of the system n-alkane/linear polyethylene. Colloid Polymer Sci 258 711-718... 

Flory PJ, Orwoll RA, Vrij A (1964) Statistical thermodynamics of chain molecule liquids. I. An equation of state for normal paraffin hydrocarbons. J Am Chem Soc 86 3507 3514 Nose T (1976) Theory of liquid liquid interface of polymer systems. Polym J 8 96 113 de Gennes P G (1977) Qualitative features of polymer demixtion. J Phys Lett 38 L441 L443 Ouhadi T, Fayt R, Jerome R, Teyssie Ph (1986) Molecular design of multicomponent polymer systems. 9. Emulsifying effect of poly(alpha methylstyrene b methlyl methacry late) in poly(vinylidene fluoride)/poly(alpha methylstyrene) blends. Polym Commun 27 212 215... 

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