Polymer/surfactant systems structure

B. Lindman and G. Karlstrom, Polymer-surfactant systems, in D.M. Bloor and E. Wyn-Jones (Eds.), The Structure, Dynamics and Equilibrium properties of Colloidal Systems. NATO ASI Series C 234,1989, pp. 131-147. 

In the past 4-5 years, quite a number of relevant review articles and books have appeared. These included general reviews on NMR of polymers (1 10), reviews on solid state NMR (11-15), solid state multidimensional techniques (16-19), spatially resolved techniques (20), solid state NMR studies of polymer dynamics and structure (21), hydrated polymers (22), vulcanized elastomers (23), crosslinked polymers (24), and polymer networks (25), Reviews have also been written on polymer gels (26-28), polymer colloids (29), polymer-surfactant systems (30), and polymers on surfaces (31). 

These findings are confirmed by study of the thermodynamic parameters of mixing of the cured epoxy resin with OP-20. At 6-7% content of surfactant, corresponding to the maximum surface tension of the polymer, a kink and an area of decrease of the Flory-Huggins parameter are observed in the dependence of X2,s on the surfactant concentration. This anomalous dependence can be explained in terms of the rearrangement of the intermolecular bonds in the polymer-surfactant system. With ED-20 initial resin, there are no extrema on the curve. Alteration of the macromolecular conformation affects the supermolecular structure of the polymer. Adding surfactant to ED-20 resin changes the form and causes a noticeable decrease of the size of the polymeric supermolecular formations. 

Leontidis, E., Kyprianidou-Leodidou, T, Caseii, W, Robyr, R, Krumeich, R, and Kyri-acou, K. C. From Colloidal Aggregates to Layered Nanosized Structures in Polymer-Surfactant Systems. 1. Basic Phenomena. The Journal of Physical Chemistry B, 105(19), 4133 144(2001). 

Ruokolainen, J., M. Torkkeli, R. Serimaa, S. Vahvaselka, M. Saariaho, G. ten Brinke, and O. Ikkala. 1996. Critical interaction strength for surfactant-induced mesomorphic structures in polymer-surfactant systems. Macromolecules 29 6621. 

Goddard ED, Leung PS. Anathapadmanabhan KP. Novel gelling structures based on polymer/surfactant systems. 16th IFSCC International Congress, Preprints, Vol 3. New York Society of Cosmetic Chemists, 1990 193-209. 

In this chapter we will discuss possible realizations of liquid crystalline ordering in conductive polymers. Section II presents basic properties of conducting polymers with a brief description of charge transport mechanisms in those systems. Section III discusses structural types and defects in liquid crystals, and Section IV covers some experimental results of the structural analysis of mesophases in polymers with flexible side chains and polymer/surfactant systems. Sections III and IV are presented to emphasize the properties important to conducting polymers. In Section V experimental data on liquid crystallinity in conductive polymers will be reviewed. Conclusion will be given in Section VI,... 

Lamellar structures of polymer/surfactant systems were studied for polyelectrolyte/surfactant systems [37] as well as for coordination complexes [38]. 

Table 13.3 gives the CMC, CAC, and PSP values for a number of polymer/surfactant systems. The variations of CAC with temperature and polymer concentration are also indicated. The ratio CAC/CMC depends on the type of polymer/surfactant combination. For example, the ratio CAC/ CMC is 0.26 for SDS/0.1% of PVP solution and 0.55 for SDS/0.1% PEO solution. This shows that even if the type of surfactant is the same, the CAC can be different for different polymers. Thus, the structure of polymer has a strong effect on the CAC. 

Since the compartmentalization occurs as a result of microphase separation of an amphiphilic polyelectrolyte in aqueous solution, an aqueous system is the only possible object of study. This limitation is a disadvantage from a practical point of view. Our recent studies, however, have shown that this disadvantage can be overcome with a molecular composite of an amphiphilic polyelectrolyte with a surfactant molecule [129], This composite was dissolvable in organic solvents and dopable in polymer film, and the microphase structure was found to remain unchaged in the composite. This finding is important, because it has made it possible to extend the study on photo-systems involving the chromophore compartmentalization to organic solutions and polymer solid systems. 

Lindman, B., Carlsson, A., Gerdes, S., Karlstroem, G., Piculell, L., Thalberg, K., et al. (1993). Polysaccharide-surfactant systems interactions, phase diagrams and novel gels. In Dickinson, E., Walstra, P. (Eds). Food Colloids and Polymers Structure and Dynamics, Cambridge, UK Royal Society of Chemistry, pp. 113-125. 

The first part of the book discusses formation and characterization of the microemulsions aspect of polymer association structures in water-in-oil, middle-phase, and oil-in-water systems. Polymerization in microemulsions is covered by a review chapter and a chapter on preparation of polymers. The second part of the book discusses the liquid crystalline phase of polymer association structures. Discussed are meso-phase formation of a polypeptide, cellulose, and its derivatives in various solvents, emphasizing theory, novel systems, characterization, and properties. Applications such as fibers and polymer formation are described. The third part of the book treats polymer association structures other than microemulsions and liquid crystals such as polymer-polymer and polymer-surfactant, microemulsion, or rigid sphere interactions. 

In the Current State of the Art we will review some of the recent SANS and reflectivity data from ISIS, which also serve to point to future directions and opportunities. Recent reflectivity measurements, on the adsorption of polymers and polymer/surfactant mixtures at interfaces, surface ordering in block copolymer systems, time dependent inter-diffusion at polymer-polymer interfaces, and the contribution of capillary waves to interfacial widths, will be described. The use of SANS to investigate the dynamic of trans-esterification of polyester blends, the deformation of copolymers with novel morphologies, and the use of diffraction techniques to determine the structure of polymeric electrolytes, will be presented. 

Nowadays nanocomposites are used in a broad variety of technical and scientific fields since they possess useful mechanical and chemical properties. Nanocomposite systems can be derived from different materials. Among these, clays are widely applied because their layered structure with high active surface area and cation exchange capacity has advantages for nanocomposite production. A possible way to improve and accelerate the incorporation of polymers (surfactants) into clay layers is the application of high-intensity ultrasonic treatment on to the suspension of a clay mineral in the presence of polymer (surfactants) molecules. Sonication promotes a drastic decrease of the incorporation time increasing the interlamellar space of clay minerals. 

It is speculated that the effect of temperature on the critical electrolyte concentration is similarly related to the effect of temperature on the structure of aqueous solutions. An increase in temperature has been shown to extend the range of micellar solutions to a higher salinity in anionic surfactant systems (31). Hence, polymer-aggregate incompatibility would be less when the temperature is increased. However, addition of alcohol or change in temperature... 

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