Nonionic polymer

CMC is compatible with most water-soluble nonionic gums over a wide range of concentrations. When a solution of CMC is blended with a solution of a nonionic polymer such as hydroxyethjlceUulose or hydroxypropylceUulose, a synergistic effect on viscosity is usuaUy observed. Such blends... 

Properties. HydroxyethjIceUulose [9004-62-0] (HEC), is a nonionic polymer. Low hydroxyethyl substitutions (MS = 0.05-0.5) yield products that are soluble only in aqueous alkali. Higher substitutions (MS > 1.5) produce water-soluble HEC. The bulk of commercial HEC falls into the latter category. Water-soluble HEC is widely used because of its broad compatibiUty with cations and the lack of a solution gel or precipitation point in water up to the boiling point. The MS of commercial HEC varies from about 1.8 to 3.5. The products are soluble in hot and cold water but insoluble in hydrocarbon solvents. HEC swells or becomes pardy to mosdy soluble in select polar solvents, usually those that are miscible with water. 

HPC is compatible with many natural and synthetic water-soluble polymers and gums (50). Generally, blends of HPC with another nonionic polymer such as HEC yield water solutions having viscosities in agreement with the calculated value. Blends of HPC and anionic CMC, however, produce solution viscosities greater than calculated. This synergistic effect may be reduced in the presence of dissolved salts or if the pH is below 3 or above 10. 

For some nonionic, nonpolar polymers, such as polyethylene glycols, normal chromatograms can be obtained by using distilled water. Some more polar nonionic polymers exhibit abnormal peak shapes or minor peaks near the void volume when eluted with distilled water due to ionic interactions between the sample and the charged groups on the resin surface. To eliminate ionic interactions, a neutral salt, such as sodium nitrate or sodium sulfate, is added to the aqueous eluent. Generally, a salt concentration of 0.1-0.5 M is sufficient to overcome undesired ionic interactions. 

Deionized water can be used as an eluent for the analysis of nonionic polymers such as pullulan and polyethylene glycol. However, in most cases, salt solutions or buffer solutions are used to decrease ionic or other interactions between samples and the stationary phase or to prevent sample association (Eigs. 6.22 and 6.23, pages 196 and 197). 

A summary of typical experimental conditions used with TSK-PW columns for nonionic polymers is described in Table 20.3. A common mobile phase is an aqueous solution of 0.05 N sodium nitrate. A salt solution of sodium nitrate is a good choice because it is not as corrosive as a solution of sodium chloride. For the descriptions and examples that follow, a bank of either five or six TSK-PW columns in series (G1000-G5000 or G1000-G6000) was used for the aqueous SEC work. These configurations allow for molecular mass characterization from less than 1,000 Da to 1,000,000 Da or greater. 

Synthetic, nonionic polymers generally elute with little or no adsorption on TSK-PW columns. Characterization of these polymers has been demonstrated successfully using four types of on-line detectors. These include differential refractive index (DRI), differential viscometry (DV), FALLS, and MALLS detection (4-8). Absolute molecular weight, root mean square (RMS) radius of gyration, conformational coefficients, and intrinsic viscosity distributions have... 

Polyacrylamides are nonionic polymers, usually with much higher molecular weights (MW from 100,000 up to 12 or 15 M). They often are copolymerized with polyacrylates. Depending on the MW ratios employed, they may act as colloidal dispersants, sludge conditioners, or flocculants. Nonionics such as polyacrylamides (and isobutylenes) are particularly useful at dispersing uncharged particles. 

AA/SA AA/SA/NI AA/SA/SSS sulfonate (polymer) aciylic acid/sulfonic acid aciylic acid/sulfonic acid/ nonionic (polymer) aciylic acid/sulfonic acid/sodium styrene sulfonate acrylic acid/sulfonic acid/substituted acrylamide (polymer)... 

TREATMENT OF EXPERIMENTAL RESULTS INTRINSIC VISCOSITIES OF NONIONIC POLYMERS ... 

Group 1 Low water (< 50%H2O) nonionic polymers Group 2 High water (> 7.50%H2O) nonionic polymers Group 3 Low water (< 50%H2O ionic polymers Group 4 High water (> 50%H2O) ionic polymers... 

Assays. Nitrogen assays to determine 1-amidoethylene unit content were done by Kjeldahl method. Limiting viscosity numbers were determined from 4 or more viscosity measurements made on a Cannon-Fenske capillary viscometer at 30°C. Data was extrapolated to 0 g/dL polymer concentration using the Huggins equation(44) for nonionic polymers and the Fuoss equation(45) for polyelectrolytes. Equipment. Viscosities were measured using Cannon-Fenske capillary viscometers and a Brookfield LV Microvis, cone and plate viscometer with a CP-40, 0.8° cone. Capillary viscometers received 10 mL of a sample for testing while the cone and plate viscometer received 0.50 mL. 

The observation that the quaternary ammonium monomer content of MDTHD.-DMAEMA and DMAEMA CH3C1 DMAEMA copolymers had little effect on their silica fines stabilization properties of prompted an investigation of nonionic polymers as mineral fines stabilizers (17,18). A series of N-vinylpyrrolidinone (NVP) copolymers with DMAEMA have been studied. Results are summarized in Table VII. 

The effectiveness of nonionic polymers as migrating clay stabilizers and the geometry of the adsorbed polymer - mineral complex may be substantially different for the nonionic polymers and the quaternary ammonium salt polymers. The observation that some quaternary ammonium salt polymers, while effective swelling clay stabilizers, are ineffective mineral fines stabilizers is consistent with a different adsorbed polymer - particle complex geometry on different mineral surfaces. 

Essentially nonionic soil-release agents comprise polyesters, polyamides, polyurethanes, polyepoxides and polyacetals. These have been used mainly on polyester and polyester/ cellulosic fabrics, either crosslinked to effect insolubilisation (if necessary) or by surface adsorption at relatively low temperature. Polyester soil-release finishes have been most important, particularly for polyester fibres and their blends with cellulosic fibres. These finishes, however, have much lower relative molecular mass (1000 to 100 000) than polyester fibres and hence contain a greater proportion of hydrophilic hydroxy groups. They have been particularly useful for application in laundering processes. These essentially nonionic polymers may be given anionic character by copolymerising with, for example, the carboxylated polymers mentioned earlier these hybrid types are generally applied with durable press finishes. 

For homopolyelectrolyte, we first studied the ellipsometric measurement of the adsorption of sodium poly(acrylate) onto a platinum plate as a function of added sodium bromide concentration (5). We measured the effect of electrolyte on the thickness of the adsorbed layer and the adsorbances of the polyelectrolyte. It was assumed that the Donnan equilibrium existed between the adsorbed layer and the bulk phase. The thickness was larger and the adsorbance of the polyelectrolyte was lower for the lower salt concentration. However, the data on the molecular weight dependence of both the adsorbance and the thickness of the adsorbed polyelectrolyte have been lacking compared with the studies of adsorption of nonionic polymers onto metal surfaces (6-9). 

For adsorption of nonionic polymer, Hoeve (15) and Jones-Richmond (16) attempted to incorporate the excluded-volume effect into the expansion factor, respectively. They suggested that the thickness of the adsorbed layer in good and 0 solvents should be taken at the same adsorbance and molecular weight3 respectively. We may calculate the expansion factor at the bulk NaPSS concentration of 0.02 g/lOOml, since the adsorbances are almost the same for the respective NaCl concentrations, as seen from Figure 5. 

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