Antipolyelectrolyte effect

The addition of simple salts leads to swelling of neutral polyampholytes if they are soluble and dissolve the precipitate if they are insoluble ( antipolyelectrolyte effect). 

Our group has examined copolymers and terpolymers from the hydrolytically resistant comonomers 1 Ij and 2 in which the cation and anion are evenly spaced from the macromolecular Imckbone (Scheme 2) 26-30). At equimolar incorporation of the monomers into the copolymer, a minimum in the apparent viscosity in water and a maximum in apparent viscosity in 0.514 MNaCl was observed - consistent with the so-called antipolyelectrolyte effect Simile effects are observed when acrylamide (3) is incorporated as a termonomer. A three-fold enhancement in viscosity was observed at a molar ratio of 11 13 76 for monomers (la 2 2) in 0.5 MNaCl as compared to deionized water (29). 

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