| abstract |
The invention described herein provides a mixture comprising polymer molecules or salts thereof, wherein a polymer molecule in the mixture comprises covalently bound subunits L, K, and M wherein the average molecular weight of the polymer molecules in the mixture is about 50 kDa to about 200 kDa, wherein the mole percentage of subunit M, relative to the total amount of subunits in the mixture, is about 90.5 to about 96 mol%, v1 herein the mole percentage of subunit K, relative to the total amount of subunits in the mixture, is about 2.8 to about 7.3 mol%, and wherein the mole percentage of subunit L, is about relative to the total amount of subunits in the mixture, 1. 2 to about 2. 2 mol%. |