Polymers aqueous

Heat Exchangers Using Non-Newtonian Fluids. Most fluids used in the chemical, pharmaceutical, food, and biomedical industries can be classified as non-Newtonian, ie, the viscosity varies with shear rate at a given temperature. In contrast, Newtonian fluids such as water, air, and glycerin have constant viscosities at a given temperature. Examples of non-Newtonian fluids include molten polymer, aqueous polymer solutions, slurries, coal—water mixture, tomato ketchup, soup, mayonnaise, purees, suspension of small particles, blood, etc. Because non-Newtonian fluids ate nonlinear in nature, these ate seldom amenable to analysis by classical mathematical techniques. 

Jeong and coworkers have reported peptide-based thermo-gelling systems using PEG-b-polyAla as an injectable cellular scaffold [315]. The polymer aqueous solution undergoes sol-gel transition as temperature increases. The fraction of the p-sheet structure of the poly Ala dictated the population and thickness of fibrous nanostructure in the hydrogel, which affected the proliferation and protein... 

PME MASE Polymeric membrane extraction, Membrane-assisted sorbent extraction Nonporous Aqueous/polymer/aqueous Organic/polymer/aqueous Aqueous/polymer/organic... 

Polystyrene-bound phenylseleninic acid has been used in catalytic amounts in a trii asic system consisting of the polymer, aqueous hydrogen peroxide, and dichloromethane, to catalyze the oxidation of al-... 

In order to aoab se the colloidal furocesses occurring in colloidal polym erization systems containing monomer, polymer monomer and polymer panicles it is important to know about adsorption characteristics of the emulsifier on the monomer-aqueous phase and polymer-aqueous phase interfaces. 

Masuda, A., Ushida, K., Nishimura, G., Kinjo, M., Tamura, M., Koshino, H., Yamashita, K. and Kluge, T. (2004) Experimental evidence of distance-dependent diffusion coefficients of a globular protein observed in polymer aqueous solution forming a network structure on nanometer scale. J Chem. Phys., 121, 10787-10793. 

Low-cost maltodextrins (Mavg = 1200,1800,3600) can be combined with polyethylene glycol (PEG) to form aqueous two-phase systems which are useful for protein separations. The physical characteristics of these maltodextrin/FEG systems are similar in many respects to dextran/FEG systems. Maltodextrins are currently available for a hundredth of the cost of fractionated dextran making the large scale application of polymer-polymer aqueous two-phase extractions more likely. The physical characteristics of the maltodextrin/FEG two-phase systems are described in this paper along with their application towards the purification of yeast alcohol dehydrogenase. 

The main drawback to the widespread use of polymer-polymer aqueous two-phase extraction has been the high cost of fractionated dextran. Crude dextran has been used with some success for the purification of enzymes but is much too viscous for many applications. Conversely, polymer-salt systems have relatively low viscosities, separate rapidly, and are inexpensive. Unfortunately, they lack selectivity and cannot be used for affinity partitioning in most cases since the high salt concentrations interfere with the protein-ligand interaction. The starch derivatives are reasonable alternatives for bottom phase polymers but have been hampered by low solubilities and the tendency for gel formation. Tjemeld has reported that chemically modified starches i.e. hydroxypropyl starch... 

Here, j = 1 for the aqueous phase, 2 for the oleic phase, and 3 for the microemulsion phase. The a parameters are determined by matching laboratory microemulsion viscosities at several compositions. In the absence of surfactant and polymer, aqueous and oleic phase viscosities reduce to pure water and oil viscosities ( a and 1 0), respectively. When polymer is present, is replaced by polymer viscosity ( Jp). Figure 7.28 shows an example of microemulsion viscosity expressed in the preceding equation, where a = (2, 3, 0, 0.9, 0.7), a = 1 cP, and j o = 5 cP. 

Figure 4.11 Scheme of a phase diagram of the system water-isooctane-AOT-PEO with the polymer content Cp as a function of the aqueous phase water content Xwp- L2 is the w/o-droplet phase in the region 2 a microemulsion coexists with an aqueous phase al specifies a solid polymer coexistence with a microemulsion in the region t2 solid polymer, aqueous polymer solution and a microemulsion are found. The real phase diagram with more phase regions is found in [52]. (From Ref. [52], reprinted with permission of the American Chemical Society.)... 

The formation of cyclic structures during the polymerization processes had led to many interesting and useful polymers. Aqueous solution of N,N-dimethyl-3,4-dimethylenepyrrolidinium bromide were found to polymerize spontaneously at 60°C. The polymerization occurs by a 1,4-addition and the polymer product has properties very similar to that of poly(N,N-dimethyldiallylammonium chloride). High molecular weight polymers were obtained with monomer concentrations of 40-50%. Higher monomer concentrations yielded insoluble gels. 

Similarly, Wasserman and coworkers have studied a wide selection of polymeric materials in aqueous solution that are associative of some kind, i.e., that form some sort of self-assembly through non-covalent interactions [96]. Their study mainly deals with hydrogels of hydrophobically modified polymers, aqueous solutions of polymeric micelles created by block copolymers, and hydrogels based on poly (acrylic acid) and macrodiisocyanates. The spin probes of choice were hydrophobic, such as 5- and 16-DSA (see Eig. 2) or even spin labeled polymers. It was, e.g., possible to screen for the effect of chemical stmcture on the gel formation by recording and understanding the local mobility of the hydrophobic, long chain spin probes as a function of temperature. 

The sample techniques just described are designed for collection of transmission (absorption) spectra. This had been the most common type of IR spectroscopy, but it was limited in its applicahons. There are many types of samples that are not suited to the convenhonal sample cells and techniques just discussed. Thick, opaque solid samples, paints, coahngs, hbers, polymers, aqueous solutions, samples that cannot be... 

Anchor polymer Aqueous dispersions Stabilizing moieties... 

JOH Johansson, H.-O., Persson, J., and Tjemeld, F., Thermoseparating water/polymer system A novel one-polymer aqueous two-phase system for protein purification,... 

Table 9.3 Latex surface polarity and polymer/aqueous phase interfacial tensions...

Dissing, U., Mattiasson, B. Partition of proteins in polyelectrolyte-neutral polymer aqueous two-phase systems. Bioseparation 1994, 4 (1), 335-342. 

For hydrolyzed sulfonic polymer, aqueous or alcoholic solutions can be made by dissolving the acid form of the polymer at 150-300°C. 

Allanic, N., P. Salagnac, and P. Glouannec, 2009a. Optimal constrained control of an infrared-convective drying of a polymer aqueous solution. Chemical Engineering Research and Design, 87(7), 908-914. 

Poly(N-(2-hydroxyproyl) methacrylamide (HPMAm)-oligolactate) (MW = 10-20 K Daltons) was linked to PEG (MW = 10 K Daltons) to show thermogelling polymer aqueous solution (Fig. 13.10). The gel modulus eould be controlled by the molecular weight of the poly(HPMAm-oligolactate) (Fig. 

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