Polyethylene imine based pigment dispersants

• US 8,268,957 B2
• Filed: 03/19/2007
• Issued: 09/18/2012
• Est. Priority Date: 03/29/2006
• Status: Active Grant

• Current Assignee: BASF SE
• Original Assignee: BASF SE
• Inventors: Liu, Yanfei, Pirrung, Frank Oliver Heinrich, Yu, Haiyang, Kou, Huiguang
• Primary Examiner(s): Listvoyb, Gregory
• Application Number:
  US12/225,642
• Publication Number:
  US 20100174046A1
• Time in Patent Office: 2,010 Days
• Field of Search: 524/599, 525/63, 525/379, 525/386, 525/415, 528/332
• US Class Current: 528/332
• CPC Class Codes: C08G 73/0206 Polyalkylene(poly)amines
• CPC Class Codes: C09B 67/009 polymeric dispersing agent
• CPC Class Codes: C09K 23/16 Amines or polyamines

Abstract

This invention refers to a novel process for the synthesis of polyethylene imine (PEI)-based pigment dispersants characterized by a “grafting from” approach, allowing the manufacture of solvent based dispersant systems. The polyethylene imine (PEI)-based pigment dispersant can be presented by the formula (I) X-(T)_m-P-(T)_n-H wherein P is a polyethyleneimine (PEI) back-bone; T is a residue —CO-A-O— wherein A is C₂-C₁₂ alkylene optionally substituted with C₁-C₆ alkyl with the proviso that each linkage between P and T is an amide bond and each linkage between X and T is an ester bond, X is a modifier or terminator residue R—CO— wherein R is a linear or branched, saturated or unsaturated alkanecarboxylic acids having from 1 to 22 carbon atoms or an unsaturated fatty acid residue or a hydroxycarboxylic residue or a polyester residue obtained from polycondensation of hydroxycarboxylic acids, or an acid terminated polyether; n, m independently are a number from 1 to 100.

Claims

1. A polyethyleneimine (PEI)-based pigment dispersant of the formula I

X-(T)_m-P-(T)_n-H

wherein

P is a polyethyleneimine (PEI) backbone;

T is a residue —

CO-A-O—

wherein A is C₄-C₅alkylene optionally substituted with C₁-C₆ alkyl with the proviso that each linkage between P and T is an amide bond and each linkage between X and T is an ester bond,

X is a modifier or terminator residue R—

CO—

wherein R—

CO—

is a residue derived from 12-hydroxystearic acid or polyhydroxystearic acid;

n, m independently are a number from 1 to 100.

3. A process to prepare a polyethyleneimine (PEI)-based pigment dispersant of the formula 1 according to claim 1 which process comprises.

4. A process according to claim 1, wherein the weight ratio of PEI to lactone monomers ranges from 1:

5 to 1;

20 and wherein the chain length of polylactones approximately ranges from 500 g/mol to 5000 g/mol.

6. A pigment dispersion comprising a compound of the formula I according to claim 1.

7. The polyethyleneimine (PEI)-based pigment dispersant of the formula I according to claim 1, wherein the dispersant is prepared by a process comprising

a) ring-opening polymerisation of lactones initiated by the primary amines and the secondary amines of a PEI macroinitiator to obtain

P-(T)_n-H

b) transesterification of grafting copolymers with the modifier or terminator X.

8. The polyethyleneimine (PEI)-based pigment dispersant according to claim 7, wherein the process is a one pot process.

9. The polyethyleneimine (PEI)-based pigment dispersant according to claim 7, wherein the weight ratio of PEI to lactone monomers ranges from 1:

5 to 1;

20 and wherein the chain length of polylactones approximately ranges from 500 g/mol to 5000 g/mol.

10. The polyethyleneimine (PEI)-based pigment dispersant according to claim 7, wherein in step a) reaction temperatures range from 60°

C. to 200°

C. under N₂ atmosphere and in step b) reaction temperatures range from 100°

C. to 200°

C. under N₂ atmosphere.

2. A process to prepare a polyethyleneimine (PEI)-based pigment dispersant of the formula I which process comprises

a) ring-opening polymerisation of lactones initiated by the primary amines and the secondary amines of a PEI macroinitiator to obtain

P-(T)_n-H

b) (trans)esterification of grafting copolymers with the modifier or terminator X.

5. A process according to claim 2, wherein in step a) reaction temperatures range from 60°

C. to 200°

C. under N₂ atmosphere and in step b) reaction temperatures range from 100°

C. to 200°

C. under N₂ atmosphere.