Packing material for ion chromatography and production method therefor

1. A packing material for ion chromatography comprising a structure in which a polyethyleneimine is bonded, directly or through a spacer, to a surface of an organic porous substrate comprising a crosslinked copolymer, and a functional group represented by formula (1) is bonded to a nitrogen atom of the polyethyleneimine:

(wherein N 1 is a nitrogen atom of the polyethyleneimine, R is an alkylene group selected from (1) an unsubstituted C1 to C10 alkylene group, (2) a C1 to C10 alkylene group having a hydroxyl group, and (3) an alkylene group in which a plurality of C2 to C4 alkylene groups are bonded by an ether bond, and R 1 , R 2 and R 3 are the same or different and represent a group selected from (1) an unsubstituted C1 to C10 alkyl group, (2) a C1 to C10 alkyl group having a hydroxyl group, and (3) a C1 to C10 alkyl group having an amino group.

2. The packing material for ion chromatography according to claim 1 , wherein R is a 2-hydroxy propylene group, and at least one of R 1 , R 2 and R 3 is a C1 to C10 alkyl group having an amino group.

3. The packing material for ion chromatography according to claim 2 , wherein the functional group represented by the formula (1) is also represented by

formula (4)

(wherein N 1 is a nitrogen atom of the polyethyleneimine);

formula (5)

(wherein N 1 is a nitrogen atom of the polyethyleneimine); or

formula (6)

(wherein N 1 is a nitrogen atom of the polyethyleneimine).

4. The packing material for ion chromatography according to claim 1 , wherein the functional group represented by the formula (1) is also represented by

formula (4)

(wherein N 1 is a nitrogen atom of the polyethyleneimine);

formula (5)

(wherein N 1 is a nitrogen atom of the polyethyleneimine); or

formula (6)

(wherein N 1 is a nitrogen atom of the polyethyleneimine).

5. The packing material for ion chromatography according to claim 1 , wherein the polyethyleneimine is bonded through a spacer to the crosslinked copolymer.

6. The packing material for ion chromatography according to claim 5 , wherein the crosslinked copolymer has a hydroxyl group, and the spacer has a structure obtained from a multifunctional glycidyl ether or epichlorohydrin.

7. The packing material for ion chromatography according to claim 6 , wherein the spacer is obtained from a multifunctional glycidyl ether, and the multifunctional glycidyl ether is selected from 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, and glycerol diglycidyl ether.

8. The packing material for ion chromatography according to claim 7 , wherein the multifunctional glycidyl ether is 1,4-butanediol diglycidyl ether.

9. The packing material for ion chromatography according to claim 1 , wherein the crosslinked copolymer is a crosslinked polyvinyl alcohol copolymer.

10. A production method of the packing material for ion chromatography according to claim 1 , comprising a step of bonding, directly or through a spacer, the polyethyleneimine to the surface of an organic porous substrate comprising a crosslinked copolymer (step 1), a step of reacting a nitrogen atom contained in the polyethyleneimine with a multifunctional glycidyl ether (step 2), and a step of reacting a tertiary amine with the glycidyl group introduced in the step 2 (step 3).

11. The production method of packing material for ion chromatography according to claim 10 , wherein the step 1 comprises a step 1a of reacting a spacer with a crosslinked copolymer having a hydroxyl group and a step 1b of reacting the polyethyleneimine with the spacer on the resultant crosslinked copolymer.

12. The production method of packing material for ion chromatography according to claim 11 , wherein the spacer is a multifunctional glycidyl ether.

13. The production method of packing material for ion chromatography according to claim 12 , wherein the spacer of the step 1a is 1,4-butanediol diglycidyl ether and the multifunctional glycidyl ether utilized in the step 2 is selected from 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol glycidyl ether, and glycerol diglycidyl ether, and the tertiary amine of the step 3 is N,N,N′,N″,N″-pentamethyl diethylene triamine.

14. The production method of packing material for ion chromatography according to claim 13 , wherein the multifunctional glycidyl ether utilized in the step 2 is glycerol diglycidyl ether.

15. The production method of packing material for ion chromatography according to claim 11 , wherein the multifunctional glycidyl ether utilized in the step 2 is selected from 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol glycidyl ether, and glycerol diglycidyl ether, and the tertiary amine of the step 3 is N,N,N′,N″,N″-pentamethyl diethylene triamine.

16. The production method of packing material for ion chromatography according to claim 11 , wherein the spacer of the step 1a and the multifunctional glycidyl ether utilized in the step 2 are each selected from 1,4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol glycidyl ether, and glycerol diglycidyl ether, and the tertiary amine of the step 3 is N,N,N′,N″,N″-pentamethyl diethylene triamine.

17. The production method of packing material for ion chromatography according to claim 10 , wherein the crosslinked copolymer is a crosslinked polyvinyl alcohol copolymer.

18. A column for ion chromatography, wherein the column is packed with the packing material according to claim 1 .

19. The packing material for ion chromatography according to claim 1 , wherein R 1 and R 2 are bonded to form a piperidine ring.

20. The packing material for ion chromatography according to claim 1 , wherein R 1 and R 2 are bonded through an oxygen atom to form a morpholine ring.