Method for preparing a polymer

Abstract

The invention relates to the preparation of a water-soluble anionic polymer, the weight-average molecular mass M.sub.W of which ranges from 1,000 to 10,000 g/mol and the polydispersity index I.sub.p of which is less than 3.5. The polymer according to the invention is obtained by a polymerization reaction in water of an unsaturated anionic monomer, in the presence of Cu.sup.I or of Cu.sup.II and of an aromatic compound comprising a functional group chosen from hydroxyl, primary amine, secondary amine and tertiary amine directly bonded to the aromatic ring. The invention also relates to an aqueous composition comprising the polymer according to the invention.

Claims

1. A process for the preparation of a water-soluble polymer, the weight-average molecular mass M.sub.w (determined by SEC) of which ranges from 1,000 to 10,000 g/mol and the polydispersity index I.sub.p, of which is less than 3.5, the process comprising performing a polymerization reaction in water, at a temperature of greater than 60° C., of at least one main monomer comprising at least one polymerizable olefinic unsaturation, in the presence: of at least one metal derivative which is complexed, bonded to at least one ligand or in the ionic form and comprising: at least one element (M) chosen from Cu.sup.1 and Cu.sup.II; or at least one precursor compound of an element (M); of at least one aromatic compound (A) comprising at least one functional group (F) selected from the group consisting of hydroxyl, primary amine, secondary amine and tertiary amine directly bonded to the aromatic ring, in an amount equivalent to at least 300 molar ppm of functional group (F) with respect to the molar amount of main monomer; and at least one initiator compound selected from the group consisting of hydrogen peroxide, sodium persulfate, potassium persulfate, ammonium persulfate, alkyl hydroperoxide and their mixtures.

2. The process according to claim 1, wherein: the at least one metal derivative is chosen from copper carbonate, copper carbonate hydrate, copper carbonate hemihydrate, copper acetate, copper sulfate, iron sulfate, iron sulfate hydrate, iron sulfate hemihydrate, iron carbonate, iron carbonate hydrate, iron carbonate hemihydrate or copper hydroxide; or the aromatic compound (A) is in an amount equivalent to at least 325 molar ppm of functional group (F), with respect to the molar amount of main monomer.

3. The process according to claim 1, for which: a weight-average molecular mass M.sub.w of the polymer is less than 9,000 g/mol; or the weight-average molecular mass M.sub.w of the polymer is greater than 1,200 g/mol; or a polydispersity index I.sub.p of the polymer is less than 3.

4. The process according to claim 3, wherein: the at least one metal derivative is chosen from copper carbonate, copper carbonate hydrate, copper carbonate hemihydrate, copper acetate, copper sulfate, iron sulfate, iron sulfate hydrate, iron sulfate hemihydrate, iron carbonate, iron carbonate hydrate, iron carbonate hemihydrate or copper hydroxide; or the aromatic compound (A) is in an amount equivalent to at least 325 molar ppm of functional group (F), with respect to the molar amount of main monomer.

5. The process according to claim 1, comprising employing: an element (M) and at least one element chosen from Fe.sup.II, Fe.sup.III, Co.sup.II, Mn.sup.II or Ni.sup.II; or an element (M) and at least one precursor compound of an element chosen from Fe.sup.II, Fe.sup.III, Co.sup.II, Mn.sup.II or Ni.sup.II; or a precursor compound of an element (M); or a precursor compound of an element (M) and at least one element chosen from Fe.sup.II, Fe.sup.III, Co.sup.II, Mn.sup.II or Ni.sup.II; or a precursor compound of an element (M) and at least one precursor compound of an element chosen from Fe.sup.II, Fe.sup.III, Co.sup.II, Mn.sup.II, or Ni.sup.II; or an element (M) and at least one precursor compound of an element chosen from Fe.sup.II, Fe.sup.III, Co.sup.II, Mn.sup.II or Ni.sup.II combined with a compound which reduces the precursor compound; or a precursor compound of an element (M) combined with a compound which reduces the precursor compound; or a precursor compound of an element (M) combined with a compound which reduces the precursor compound and at least one element chosen from Fe.sup.II, Fe.sup.III, Co.sup.II, Mn.sup.II or Ni.sup.II; or a precursor compound of an element (M) and at least one precursor compound of an element chosen from Fe.sup.II, Fe.sup.III, Co.sup.II, Mn.sup.II or Ni.sup.II combined with a compound which reduces the precursor compound.

6. The process according to claim 1, wherein the aromatic compound (A) is hydroxylated and is selected from the group consisting of benzoquinone, hydroquinone, catechol, pyrocatechol, tert-butylpyrocatechol, gallic acid, tannic acid, tannic liquor, 4-hydroxybenzoic acid, 4-aminophenol, salicylic acid, syringic acid, dopamine or dopamine-HCl, resorcinol, lignosulfonate, curcumin, para-methoxyphenol, anthocyanidins, humic acid and their mixtures.

7. The process according to claim 1, wherein the main monomer is an anionic monomer.

8. The process according to claim 1, further comprising the use of at least one comonomer.

9. The process according to claim 1, wherein the process is carried out in water.

10. The process according to claim 9, wherein the process is carried out in deionized water.

11. The process according to claim 1, wherein the process is carried out in the absence of chain-transfer agent.

12. The process according to claim 1, wherein the process is carried out in an aqueous medium or in the absence of organic solvent or carried out in an aqueous medium and in the absence of organic solvent.

13. The process according to claim 1, wherein the reaction medium comprises a mass amount of less than 6,000 ppm, with respect to the mass amount of main monomer, of salt chosen from sulfates, sulfites, phosphates, phosphites or hypophosphites.

14. The process according to further comprising performing complete or partial neutralization of the polymer.

15. A polymer of at least one main monomer comprising at least one polymerizable olefinic unsaturation, the molecular mass M.sub.w (determined by SEC) of which is less than 10,000 g/mol and the polydispersity index I.sub.p of which is less than 3.5, obtained according to the process of claim 1 and not comprising a residual volatile organic compound or comprising an amount of salt chosen from sulfates, sulfites, phosphates, phosphites or hypophosphites which is less than 2,000 ppm, with respect to the amount of main monomer.

Description

(1) The examples which follow make it possible to illustrate the different aspects of the invention.

(2) A mixture (1) defined according to Tables 1, 2 and 3 is charged to a 1,000 ml reactor equipped with a mechanical stirrer, with heating by an oil bath and with a system for measuring the temperature which makes possible thermal regulation. The aromatic compound (A) is introduced into the reactor (1). The reactor is then heated to a temperature of 93±2° C.

(3) When this temperature is reached, peristaltic pumps equipping the reactor make it possible to simultaneously inject the mixture (2) and the mixture (3) which are prepared beforehand and defined according to Tables 1, 2 and 3. A temperature of 93±2° C. is maintained.

(4) The duration of injection of the mixture (1) is 120 min and the duration of injection of the mixture (3) is 150 min. Once the injections are complete, the reactor is allowed to cool.

(5) Weight-average molecular mass M.sub.W and polydispersity index I.sub.p are measured and calculated after complete neutralization with sodium hydroxide solution of the samples of polymer prepared.

(6) The characteristics of the polymers according to the invention and of comparative polymers are presented in Tables 1, 2 and 3 (amounts expressed in g).

(7) TABLE-US-00001 TABLE 1 Polymer Comparative According to the invention Example 1 2 3 4 5 6 7 8 9 Element (M) Fe.sup.II Fe.sup.III/Fe.sup.II Mn.sup.II Co.sup.II/Fe.sup.II Cu.sup.II Cu.sup.II Cu.sup.II Cu.sup.II Cu.sup.II Aromatic compound (A) gallic hydroquinone gallic gallic pyrocathecol gallic gallic gallic gallic acid acid acid acid acid acid acid Reactor raw water 245 245 245 245 245 245 245 245 245 (1) Cu(OH).sub.2•CuCO.sub.3 0 0 0 0 0 0.771 0 0 0 Cu acetate 0 0 0 0 0.37 0 0 0 0 CuSO.sub.4•5H.sub.2O 0 0 0 0 0 0 2.258 0.74 3.84 CoSO.sub.4•7H.sub.2O 0 0 0 0.727 0 0 0 0 0 FeSO.sub.4•7H.sub.2O 1.0300 0.3105 0 0.3105 0 0 0 0 0 FeCl.sub.3 0 0.419 0 0 0 0 0 0 0 Mn acetate•4H.sub.2O 0 0 1.71 0 0 0 0 0 0 acrylic acid 5 5 5 5 5 5 5 5 5 Main acrylic acid 274.822 274.822 274.822 274.822 274.822 274.822 274.822 274.822 274.822 monomer (2) Initiator raw water 9.4 9.4 9.4 9.4 9.4 9.4 9.4 9.4 9.4 (3) 35% H.sub.2O.sub.2 35.3 35.3 35.3 35.3 35.3 35.3 35.3 35.3 35.3 M.sub.w (g/mol) 30,000 36,310 173,940 30,275 9,755 5,695 4,400 8,465 5,125 I.sub.p 4.8 5.2 15.3 5.1 3.0 2.6 2.3 3.0 2.5 Functional group (F)/ 643 654 1,024 751 654 1,024 1,024 1,024 1,024 amount of main monomer molar ratio (ppm)

(8) TABLE-US-00002 TABLE 2 Polymer according to the invention Example 10 11 12 13 14 15 16 Element (M) Fe(II)/Cu(II) Fe(II)/Cu(II) Cu(I)/Fe(II) Cu(II)/Fe(III) Fe(II)/Cu(II) Fe(II)/Cu(II) Fe(II)/Cu(II) Aromatic compound (A) hydroquinone pyrocathecol gallic acid 1,4-benzoquinone curcumin tannic acid resorcinol Reactor raw water 245 245 245 245 245 245 245 (1) Cu(OH).sub.2•CuCO.sub.3 0.286 0.572 0 0 0.286 0.286 0.286 CuSO.sub.4•5H.sub.2O 0 0 0 0.646 0 0 0 CuBr 0 0 0.371 0 0 0 0 FeSO.sub.4•7H.sub.2O 0.3105 0.621 0.3105 0 0.3105 0.3105 0.3105 FeCl.sub.3 0 0 0 0.181 0 0 0 acrylic acid 5 5 5 5 5 5 5 Main acrylic acid 274.822 274.822 274.822 274.822 274.822 274.822 274.822 monomer (2) Initiator raw water 9.4 9.4 9.4 9.4 9.4 9.4 9.4 (3) 35% H.sub.2O.sub.2 35.3 70.6 35.3 35.3 35.3 35.3 35.3 M.sub.w (g/mol) 5,400 3,135 7,120 5,235 6,480 6,005 5,800 I.sub.p 2.5 2.1 2.8 2.4 2.7 2.6 2.5 Functional group (F)/main 654 654 751 1,033 312 645 770 monomer molar ratio (ppm)

(9) TABLE-US-00003 TABLE 3 Polymer according to the invention Example 17 18 19 20 21 22 Element (M) Fe(II)/Cu(II) Fe(II)/Cu(II) Fe(II)/Cu(II) Fe(II)/Cu(II) Fe(II)/Cu(II) Fe(II)/Cu(II) Aromatic compound (A) 4-aminophenol syringic aid dopamine (.HCl) salicylic 4-hydroxybenzoic hydroquinone acid acid Reactor (1) raw water 245 245 245 245 245 245 Cu(OH).sub.2•CuCO.sub.3 0.286 0.286 0.286 0.286 0.286 0.286 CuSO.sub.4•5H.sub.2O 0 0 0 0 0 0 CuBr 0 0 0 0 0 0 FeSO.sub.4•7H.sub.2O 0.3105 0.3105 0.3105 0.3105 0.3105 0.3105 FeCl.sub.3 0 0 0 0 0 0 acrylic acid 5 5 5 5 5 5 Main acrylic acid 274.822 274.822 274.822 274.822 274.822 274.822 monomer (2) Initiator (3) raw water 9.4 9.4 9.4 9.4 9.4 9.4 35% H.sub.2O.sub.2 35.3 35.3 35.3 35.3 35.3 35.3 M.sub.w (g/mol) 5,380 5,900 5,635 6,050 6,000 5,700 I.sub.p 2.5 2.6 2.5 2.6 2.6 2.5 Functional group (F)/amount of 776 298 496 377 377 1,570 main monomer molar ratio (ppm)