| abstract |
Described herein is a process for flocculating an aqueous suspension of finely divided particles which comprises treating the suspension with an effective amount of a water-soluble graft copolymer to achieve the desired degree of flocculation of said particles, said water soluble graft copolymer being comprised of polymeric units characterized by the general formula: <IMAGE> wherein n, y and z represent the relative molar equivalent fractions of each of the respective polymeric units in the graft copolymer, the sum of n, y and z being 1.0, the value of n varying from 0.00 to 0.99, the value of y varying from 0.00 to 0.99 and the value of z varying from 0.01 to 0.99; q is an integer greater than 1; A is the unit derived from at least one difunctional amine selected from the group consisting of primary amines and di(secondary)amines; t is an integer varying from 1 to 2; E is the unit obtained from a compound selected from the group consisting of epihalohydrins and diepoxides after its reaction with said difunctional amine; R is an organic radical derived from a quaternizing agent having the general formula RX, where X is the residual counter ion formed after quaternization; B is the unit derived from an organic dihalide having the general formula BY2, where Y is Cl-, Br- or l- with the proviso that such halogens are not attached to the same carbon atom; and C is the unit derived from an organic di(tertiary)amine after its reaction with said organic dihalide. |