Solubilization surfactant-polymer systems

These anomalies, found in several different surfactant-polymer systems under different conditions, clearly indicate that the interaction between the surfactant and the polymer slows down the dynamics of the solubilized molecules. 

Surfactant—polymer systems have additional technological significance since surfactants are normally used in the emulsion polymerization of many materials, often involving the solubilization of monomer in micelles prior to polymerization and particle formation. Surfactants have also been shown to increase the solubility of some polymers in aqueous solution. The combined actions of the surfactant as a locus for latex particle formation (the micelle) in some cases, particle stabilization by adsorbed surfactant, and as a solubilizer for monomer permit us to expect quite complex relationships between the nature of the surfactant and that of the resulting latex. 

As will be discussed in more detail in Chapter 16, a useful characteristic of many micellar systems is their ability to solubilize otherwise water-insoluble materials such as hydrocarbons, dyes, flavors, or fragrances. Some surfactant-polymer complexes have been shown to solubilize materials at surfactant concentrations well below the cmc of the surfactant in the absence of polymer. The effectiveness of such complexes differs quantitatively from that of conventional micelles. 

A well-known feature of surfactant solutions is their ability to dissolve a variety of oil-soluble materials, e.g., hydrocarbons, esters, perfumes, dyes, and so on. This property is utilized in the compounding of many formulations, the process involving the dissolution of the solubihzate in the surfactant micelles. Formation of polymer/surfactant complexes is currently regarded as a depression of the critical aggregation concentration of the surfactant. According to this picture, superior solubilization in such systems can be anticipated... 

Uses Antisoiling agent, improves weatherability in paints, coatings, sealers coupling agent for fillers in performance polymer systems surfactant in oil field applications solubilizer for paraffins Features High electrolyte tolerance... 

Interactions between polymers and surfactants have been widely investigated in the recent decades. The interaction may lead to a polymer-surfactant complex formation, which may have a significant influence on the system properties e.g. emulsification, colloidal stability, viscosity enhancement, gel formation, solubilization, and phase separation [Goddard 1993a Goddard 2002]. The properties and structure of surfactant-polymer complexes depend on the molecular characteristics of both the polymer and surfactant [Lindman Thalberg,... 

Various types of amphiphilic water-soluble polymers have been a focus of considerable interest over the past decade from both scientific and practical perspectives. The scientific interests are derived from their molecular selforganization phenomena, which are relevant to biological polymer systems and to their nanoscopic molecular frameworks as a basis of materials science. Practical interests stem from their usefulness in a variety of applications, such as polymeric surfactants, emulsifiers, solubilizers, associative thickeners, rheology modifiers, flocculants, and colloid stabilizers. These applications are particularly important in such industries as paint, coating, printing, paper, ceramic, drug, and cosmetic or personal care goods [1-3]. In addition, these water-based polymers have become more important than ever as environmentally friendly materials. 

One parameter that has been discovered to be crucially important in the successful implementation of the surfactant-polymer flooding process is the salinity of the aqueous phase. As discussed previously, addition of salt to the microemulsion system induces the change from lower- to middle- to upper-phase microemulsion (Fig. 15) [33]. It was found that at a particular salt concentration, deemed the optimal salinity, a number of important parameters were optimized for the oil recovery process. The optimal salinity was found to occur when equal amounts of oil and brine were solubilized by the middle-phase microemulsion [50]. 

In this paper, the results on solution and Interfaclal properties of a cationic celluloslcs polymer with hydrophobic groups are presented. Interaction of such polymers with added surfactants can be even more complex than that of "unmodified" polymers. In the past we have reported the results of Interactions of unmodified cationic polymer with various surfactants Investigated using such techniques as surface tension, preclpltatlon-redlssolutlon, viscosity, solubilization, fluorescence, electroklnetlc measurements, SANS,etc.(15-17). Briefly, these results showed that as the concentration of the surfactant Is Increased at constant polymer level significant binding of the surfactant to the polymer occurred leading to marked Increases In the surface activity and viscosity. These systems were able to solubilize water Insoluble materials at surfactant concentrations well below the CMC of polymer-free surfactant solutions. Excess surfactant beyond that required to form stoichiometric complex was found to solubilize this Insoluble complex and Information on the structure of these solubilized systems has been presented. 

Poly(propylene oxide) is typically obtained by base catalyzed anionic polymerization of propylene oxide [12]. Both stereospecific and atactic forms are known. The polymer is used as a soft polyether unit in polyurethane elastomers and foams in polymer electrolytes as surfactants (lubricants, dispersants, antistatic agents, foam control agents) in printing inks, as solubilizers in hydraulic fluids, coolant compositions in various medical applications (protective bandages, drug delivery systems, organ preservation, dental compositions), etc. 

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