Sodium chloride copolymers

Hydrolysis. The starting material for the hydrolysis reaction is a 2.0 g sample of previously prepared, graft copolymer(41,42). The copolymer is hydrolyzed in a basic, saline, aqueous solution under anaerobic conditions. Sufficient copolymer is dissolved in sufficient sodium chloride brine to form a combined, final reaction mixture of 2 g/dL copolymer in 1.0 M sodium chloride. Sufficient sodium hydroxide is dissolved in water to yield a final concentration in the combined reaction mixture of 0.5 M. The solutions are saturated with nitrogen, warmed to 40°C, combined, and allowed to react with stirring for 10 minutes under a nitrogen blanket. 

Solutions containing 0.15 g/dL polymer and between 0 and 0.342 molar sodium chloride or between 0 and 2.49 x 10 molar calcium chloride show declines in viscosity as salt content increases. Solution viscosity of nonionic copolymers declines, at most,... 

The data show that calcium chloride is 20 times more effective on a concentration basis in compacting hydrolyzed copolymers than is sodium chloride. Radii of gyration shown in Table 4 are calculated with the Flory equation,... 

Figure 7. Effect of sodium chloride concentration on the viscosity of hydrolyzed poly(starch g-(2 propenamide)) copolymer solutions.

Viscosity of copolymer solutions decreases by, at most, 3 percent when electrolyte concentration changes from 0 to 0.342 M sodium chloride or 2.45 x 10 M calcium chloride. Viscosity of hydrolyzed polymer solutions decreases exponentially with increasing electrolyte concentration in water. 

Conditions columns, Asahipak GS320 (vinyl alcohol copolymer gel), 50 cm x 7.6 mm i.d. eluent, 0.1 M sodium phosphate containing 0.3 M sodium chloride pH 7.0 flow rate, 1 ml min-1 detection, UV 250 nm direct injection of sample. Peaks l, protein, 2, orotidine 3, creatinine, and 4, uric acid. 

As observed for other copolymers that exhibit an LCST (3), sodium chloride depresses the LCST of NIPAAM copolymers (Figure 6). The difference appears to be very large for NIPAAM copolymers in 0.9 M sodium chloride versus PBS (15 to over 20 C). These studies indicated that the NIPAAM-AAM copolymer that precipitated most efficiently above 55 C and below 65 C in 0.9M NaCl contained 67% NIPAAM and 33% AAM. 

Another application of this methodology is to use several different copolymers to detect multiple analytes in a single sample. Each polymer would have a different antibody attached and be precipitated at a different temperature. This appears to be possible since one copolymer that precipitates at a lower temperature does not appear to remove a copolymer with a higher LCST from solution. (J. H. Priest, unpublished observations). It is also conceivable that a DNA probe-based assay could be included with a panel of immunoassays. After removal of the various antibody-copolymer conjugates at lower temperature sodium chloride would be added, the hybridization would be performed at 55 C and the DNA-copolymer conjugates precipitated at 65 C. 

Fig. 6. Isothermal phase transitions from the phase separated to homogeneous state of the aqueous solution of the copolymer containing 11.6 mol % pendant crown ether groups by the addition of (O) potassium and (9) sodium chlorides at 32 °C and 37 °C. Polymer concentration was 1 mass %...

A 90 x 6 cm column was packed with 2 kg of granular Amberlite IRA-410 resin in the chloride form (a vinylpyridine/divinylbenzene copolymer quaternized with dimethyl sulfate and converted to chloride) and washed with 3 kg of a 10% aqueous solution of sodium cyanate. This changed the resin from the chloride to the cyanate form. Sodium chloride and excess sodium cyanate were then washed from the column with distilled water until the effluent failed to give a white precipitate with silver nitrate. The reaction of equation (2) was conducted by elutriating the column with a solution of 105 grams (1.5 mols) of hydroxylamine hydrochloride in 400 ml water at about 15°C. 

In another report, a 50 nm thick poly(styrene-h-methylmethacrylate) block copolymer film with spherical domains was prepared on a sodium chloride monocrystal and coated by a thin layer of gold, replicating the domain pattern. Similar results were also obtained with poly(styrene-h-2-vinylpyridines) [113]. 

Salt rejections by the NS-300 membrane toward synthetic seawater improved as the isophthalamide content of the barrier layer increased. Surprisingly, membrane flux peaked rather than simply declining as a function of increasing isophthalamide content. This is illustrated by the data in Table II. Maximum water permeability characteristics were found at an approximate copolymer ratio of 67 percent isophthalic and 33 percent trimesic groups. The differences in the magnesium sulfate versus sodium chloride rejection appear to be due to the anionically charged nature of the membrane barrier layer, which is rich in carboxylate groups. 

A copolymer of this monomer with N,N melhylenebis (acrylamide) imbibed 100 times its weight of water. This swelling was not affected by sodium chloride in the water. Most super-slurpers swell less in the presence of dissolved salts. Thus, the new copolymer may be of use in collecting urine in diapers. Another polymeric hydrogel was made by polymerization of sucrose-l -acrylate using sucrose-6,1 -diacrylate (prepared by enzymatic transesterification of sucrose and vinyl acrylate) as the cross-linking agent.155... 

Apicella, A. andH.B. Hopfenberg, "Hater-Swelling Behavior of an Ethylene-Vinyl Alcohol Copolymer in the Presence of Sorbed Sodium Chloride", J Mem Sci 1982, 27., pp 1139-1148. 

The two insoluble compounds precipitate and are removed from the water by filtration. Thus by the successive usage of cation and anion-exchange resins sodium chloride could be removed from water. An example of a cation-exchange resin is sulfonated styrene-divinyl-benzene polymer and an anion-exchange resin can be made by chloromethylating styrene-divinyl copolymer and replacing the chlorines with tr i me thy1ami ne. 

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