Patent ID: 11931928
Assignee: EVONIK SUPERABSORBER LLC
Field: Other special machines (Mechanical engineering)
Classification: CPC B  C | IPC B  C

Claim 9:
10. A process to make continuous strand superabsorbent polymer, the process comprises:
a) providing a monomer mixture comprising water, a polymerizable unsaturated acid group containing monomer, a crosslinker and an initiator;
b) transporting the monomer mixture of step a) into a confining means wherein the monomer mixture is cross-sectionally confined in said confining means; wherein “cross-sectionally confined in said confining means” refers to continuous tube that is capable of confining a monomer in at least one axis direction perpendicular to the monomer flow as the monomer moves through the confining means, causing the monomer to polymerize to polymerize into a continuous strand having a cross-sectional diameter of 0.1 mm to 10 mm;
c) initiating polymerization of the monomer mixture in one continuous step in the confining means;
d) emitting a continuous strand superabsorbent polymer from the confining means wherein the continuous strand superabsorbent polymer has a defined cross-sectional profile comprising an initial cross sectional diameter of from 0.1 mm to 10 mm immediately prior to exiting said confining means, and
e) cutting the continuous strand superabsorbent polymer into superabsorbent polymer particles;
wherein the diameter of the strand is retained in the diameter of the particle in at least one axis, or in at least two axes, taking into account any shrinkage that occurs during drying of the polymer; and
wherein the confining means is an elastic tube, which can be penetrated by electromagnetic radiation with wave length between 300 nm up to 500 nm.