SUPER ABSORBENT POLYMER AND A PREPARATION METHOD THEREOF

摘要

The present invention relates to a super absorbent polymer (SAP) and a preparation method thereof. More specifically, the present invention provides a SAP satisfying the overall properties required to a SAP and especially the superior initial absorbency and absorbing rate under load at the same time, and a preparation method thereof, by treating the surface of the SAP with a surface treatment solution including water and a diol-based or glycol-based surface crosslinking agent.

主权项

1. A super absorbent polymer (SAP), having the SPAN value of 1.2 or less, represented by the following Mathematical Formula 1, and
satisfying the absorbing rate under load represented by the following Mathematical Formula 2:
SPAN=[D(90%)−D(10%)]/D(50%)≦1.2  [Mathematical Formula 1] in Mathematical Formula 1, D(90%) is the diameter of the particle when the accumulated weight from the smallest particle becomes 90%, D(10%) is the diameter of the particle when the accumulated weight from the smallest particle becomes 10%, and D(50%) is the diameter of the particle when the accumulated weight from the smallest particle becomes 50%,
1.0>ARUL=AUP(10 min)/AUP(60 min)>0.70  [Mathematical Formula 2] in Mathematical Formula 2, ARUL is the absorbing rate under load, AUP (10 min) is the absorbency under pressure after 10 mins represented by the following Mathematical Formula 3, and AUP (60 min) absorbency under pressure after 60 mins represented by the following Mathematical Formula 3,
AUP(g/g)=[Wb(g)−Wa(g)]/weight of absorbent polymer(g)  [Mathematical Formula 3] in Mathematical Formula 3, Wa (g) is the sum of the weight of the absorbent polymer and the weight of the device capable of providing load to the absorbent polymer, and Wb (g) is the sum of the weight of the absorbent polymer in which moisture is absorbed under load (0.7 psi) for 1 hr and the weight of the device capable of providing load to the absorbent polymer.