Hydrophobically modified ethyl

Karlberg, M., Thuresson, K., Lindman, B. (2005). Hydrophobically modified ethyl (hy-droxyethyl)cellulose as stabilizer and emulsifying agent in macroemulsions. Colloids and Surfaces A Physicochemical Engineering Aspects, 262, 158-167. 

Amphiphilic polymers can have a strong impact on the phase behaviour of microemulsions already at very low concentrations. The most drastic consequence is that on the emulsification capacity of surfactants. A first work in this respect was carried out using hydrophobically modified ethyl hydroxyethyl cellulose [ 1 ]. This is a comb-shaped polymer, having a water-soluble backbone functionalised with low molecular weight hydrophobic... 

Thuresson, K., B. Nystroem, G. Wang, and B. Lindman (1995). Effect of surfactant on structural and theimo-dynamic properties of aqueous solutions of hydrophobically modified ethyl (hydroxyethyl) cellulose. Langmuir 11(10) 3730-3736. 

BAD Badiger, M.V., Lutz, A., and Wolf, B. A., Interrelation between the thermodynamic and viscometric behaviotrr of aqueous solutions of hydrophobically modified ethyl hydroxyethyl cellttlose. Polymer, 41, 1377, 2000. 

A series of membrane materials have been tested for the performance of water removal from hydrazine, including poly(vinyl alcohol) (PVA), ethyl cellulose, PS, and ABS (93). Contact angle measurements served to estimate the hydrophilic or hydrophobic properties. Apolar materials showed higher separation factors than polar materials. Encouraging results with respect to the performance were obtained with modified ethyl cellulose and ABS membranes. 

Viscosity Maxima. The low-shear-rate viscosities of both commercial and model associative thickeners below their c /, values will increase with the addition of conventional low molecular weight surfactants or coalescing aid (22). With HEUR polymers, solution viscosities are observed to increase, achieve a maximum value, and then decrease with continued increase in surfactant concentration (23). This type of behavior is illustrated (Figure 5) for four commercial HEURs with a nonionic surfactant (typical of that used in coating formulations). A similar behavior has been observed (24) with a classical anionic surfactant and hydrophobically modified (hydroxy-ethyl)cellulose (HMHEC) and is reviewed in Chapter 18. Intermicellar networks, formed by the participation of one or more hydrophobes from different polymers in the micelles of conventional surfactants, were again recently suggested (25) to affect viscous solutions. 

Non-ionic, hydrophobically-modified hydroxy ethyl cellulose (HMHEC). 

Chem. Descrip. Ethyl hydroxyethyl cellulose, hydrophobically modified CAS 9004-58-4... 

Pulsed gradient spin echo NMR was used to measure the diffusion coefficients of hydrophobically modified alkali-swellable (HASH) associating polymers (AP) in aqueous solution. The HASH APs consisted of a methacrylic acid-ethyl acrylate copolymer to which hydrophobic sticker ... 

There are three main classes of thickeners, which are commonly used CeUulosics (modified natural products, usually hydroxy-ethyl cellulose - HEC), HASE (hydrophobic-ally modified alkali-sweUable emulsions) and HEUR (hydrophobically modified ethylene oxide urethanes). 

Aleksic et al. [47] estimated the hydrophobicity of miconazole and other antimycotic drugs by a planar chromatographic method. The retention behavior of the drugs have been determined by TLC by using the binary mobile phases acetone-n-hexane, methanol toluene, and methyl ethyl ketone toluene containing different amounts of organic modifier. Hydrophobicity was established from the linear relationships between the solute RM values and the concentration of organic modifier. Calculated values of RMO and CO were considered for application in quantitative structure activity relationship studies of the antimycotics. 

The same hyperbranched polyglycerol modified with hydrophobic palmitoyl groups was used for a noncovalent encapsulation of hydrophilic platinum Pincer [77]. In a double Michael addition of ethyl cyanoacetate with methyl vinyl ketone, these polymer supports indicated high conversion (81 to 59%) at room temperature in dichloromethane as a solvent. The activity was stiU lower compared with the noncomplexed Pt catalyst. Product catalyst separation was performed by dialysis allowing the recovery of 97% of catalytic material. This is therefore an illustrative example for the possible apphcation of such a polymer/catalyst system in continuous membrane reactors. 

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