Surfactants polymer grafted

Abele, S., Gauthier, C., Graillat, C. and Guyot, A. (2000) Films from styrene-butyl acrylate lattices using maleic or succinic surfactants mechanical properties, water rebound and grafting of the surfactants. Polymer, 41, 1147-55. 

Fluorinated surfactants or graft polymers are typically necessary in C02 applications [48, 49]. Research into the self-assembly of these surfactants and polymers in C02 have focused on dilute systems where only reverse water-in-C02 micelles are expected [39, 50-52, 53]. Regions of the phase diagrams where C02-in-water micelles, bicontinuous microemulsions or liquid crystalline phases are formed remain to be investigated in detail. There is only one system known so far where all these phases have been observed. We will come back to this at the end of Section 7.4. The properties of reverse micelles in C02... 

Peng BL, Han X, Liu HL, Berry RC, Tam KC (2013) Interactions between surfactants and polymer-grafted nanocrystalline cellulose. Colloid Surf A Physicochem Eng Asp... 

Surface modification by polymer adsorption is an alternative to surface modification by polymer grafting. For example, polystyrene nanospheres coated by Poloxamer or Poloxamine (Ilium and Davis, 1983 Muller, 1991) or poly(methyl methacrylate) colloidal carriers coated by Poloxamer (Trds-ter and Kreuter, 1988) circulate longer in blood. This family of surfactants consist of poly(propylene glycol) (PPG) blocks, which adsorb on the hydrophobic polystyrene surface, and of more hydrophilic PEG blocks, which stick out of the surface in aqueous solutions and prevent opsonin adsorption. In spite of the increase in blood circulation time, particle coating by polymer adsorption was found to have several drawbacks (Petrak, 1993) ... 

The deposition of particles on surfaces is a process that is determined by long-range forces Van der Waals attraction, electrostatic repulsion or attraction and the presence of adsorbed or grafted surfactants, polymers or polyelectrolytes (referred to as steric interaction). 

In most cases, in situ suspension polymerization is carried out with nanoparticles dispersed in monomers. The surface modification of nanoparticles is usually required in order to achieve a good dispersion. Since the mechanism of in situ suspension polymerization is similar to that of in situ bulk polymerization, the surface modification used in bulk polymerization, including ion-exchange reaction, surfactant and coupling agent, polymer grafting and acid treatment can also be applied here. 

Emulsion polymerizations of vinyl acetate in the presence of ethylene oxide- or propylene oxide-based surfactants and protective coUoids also are characterized by the formation of graft copolymers of vinyl acetate on these materials. This was also observed in mixed systems of hydroxyethyl cellulose and nonylphenol ethoxylates. The oxyethylene chain groups supply the specific site of transfer (111). The concentration of insoluble (grafted) polymer decreases with increase in surfactant ratio, and (max) is observed at an ethoxylation degree of 8 (112). 

Tethering may be a reversible or an irreversible process. Irreversible grafting is typically accomplished by chemical bonding. The number of grafted chains is controlled by the number of grafting sites and their functionality, and then ultimately by the extent of the chemical reaction. The reaction kinetics may reflect the potential barrier confronting reactive chains which try to penetrate the tethered layer. Reversible grafting is accomplished via the self-assembly of polymeric surfactants and end-functionalized polymers [59]. In this case, the surface density and all other characteristic dimensions of the structure are controlled by thermodynamic equilibrium, albeit with possible kinetic effects. In this instance, the equilibrium condition involves the penalties due to the deformation of tethered chains. 

Fig. 10 Aggregation numbers 2 as function of degree of polymerization of insoluble block for uncharged block copolymers. Open symbols different diblock-, triblock-, graft-, and star polymers. Filled symbols low-MW surfactants. Reprinted with permission from [211]. Copyright (2002) Wiley...

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